Neuroplasticity-based cognitive training in schizophrenia: an interim report on the effects 6 months later

Pharmacologic Augmentation of Computerized Auditory Training in Chronic Psychosis: Preliminary Findings From a Single-Site, Double-Blind Study

BACKGROUND

Computerized auditory training (AT) modestly improves symptoms, cognition, and functioning in schizophrenia. We assessed whether d-amphetamine (AMPH) or memantine (MEM) can enhance gains from 30-h of AT.

METHODS

Antipsychotic-medicated individuals with chronic psychosis (n = 68; mean age 47.03y; M:F = 39:29) completed up to 30 AT sessions (2-3/week; n = 50 completed 30 sessions) in 3 groups: "AMPH group" (AMPH (5 mg po) 1-h before each AT session); "MEM group" (titrated to 10 mg MEM bid and maintained that dose throughout training); "PBO group" (PBO dosed identically to either AMPH or MEM). Primary (PANSS total, MCCB Composite, WHODAS) and secondary (PANSS positive, PANSS negative, YMRS, PHQ-9, PSYRATS) outcome measures were acquired at baseline, after 10, 20, and 30 AT sessions, and 12 weeks post-training. Pill identity (active/PBO) was blind to subjects and staff.

RESULTS

Marginally significant between-group gains for AMPH vs PBO were detected for one of three primary outcomes (WHODAS, P =.050; but not PANSS total or MCCB Composite), and for 3 of 5 secondary clinical outcomes (PANSS positive, YMRS, PSYRATS, P's≤.027-.049). Within-subject gains over time were detected for primary and secondary clinical measures for AMPH (P's≤.014-.004) and MEM (P's≤.02-.001) groups; some of these would not survive conservative correction for multiple comparisons. No measures detected symptom worsening; treatment satisfaction exceeded subjects' expectations.

CONCLUSIONS

Results are mixed; drug-associated gains in several measures vs PBO suggest that these regimens may augment AT-induced functional and clinical improvement in psychosis patients, independent of changes in neurocognition. Assessment in larger samples seems warranted.

Efficacy of cognitive training on cognition, symptoms and functioning: Impact of motivation and attendance

While cognitive remediation therapy (CRT) and compensatory strategy training both have large literature bases supporting their efficacy on both proximal and distal outcomes, the research base on stand-alone cognitive training (CT) is smaller and less consistent, with little information about factors associated with better outcomes. In this study, we examined the efficacy of CT on training task, cognitive, symptom, and functional ability measures as well as the impact of motivational interviewing (MI), motivation level, and session attendance on treatment outcomes. Adults with psychotic spectrum disorders (n = 114) were randomized to MI or a sham control interview (CI), followed by 4 months of computerized CT. In whole sample analyses, participants improved on training tasks, cognitive performance, and psychiatric symptoms, but self-reported cognition, self-reported depression, and functional ability did not change. Compared to CI, MI was associated with greater reductions in self-reported depressive symptoms. Motivation level and session attendance did not significantly influence outcomes. Findings support the efficacy of CT on several key outcomes, and its simplicity may be advantageous in uptake in community clinics with limited staffing. The lack of functional gains underscores the need to incorporate treatment ingredients that promote generalization and real-world implementation of learned skills. We also speculate that engagement during course of training may be a better predictor of training success than baseline task-specific motivation.

Personalized Cognitive Health in Psychiatry: Current State and the Promise of Computational Methods

BACKGROUND

Decades of research have firmly established that cognitive health and cognitive treatment services are a key need for people living with psychosis. However, many current clinical programs do not address this need, despite the essential role that an individual's cognitive and social cognitive capacities play in determining their real-world functioning. Preliminary practice-based research in the Early Psychosis Intervention Network early psychosis intervention network shows that it is possible to develop and implement tools that delineate an individuals' cognitive health profile and that help engage the client and the clinician in shared decision-making and treatment planning that includes cognitive treatments. These findings signify a promising shift toward personalized cognitive health.

STUDY DESIGN

Extending upon this early progress, we review the concept of interindividual variability in cognitive domains/processes in psychosis as the basis for offering personalized treatment plans. We present evidence from studies that have used traditional neuropsychological measures as well as findings from emerging computational studies that leverage trial-by-trial behavior data to illuminate the different latent strategies that individuals employ.

STUDY RESULT

We posit that these computational techniques, when combined with traditional cognitive assessments, can enrich our understanding of individual differences in treatment needs, which in turn can guide evermore personalized interventions.

CONCLUSION

As we find clinically relevant ways to decompose maladaptive behaviors into separate latent cognitive elements captured by model parameters, the ultimate goal is to develop and implement approaches that empower clients and their clinical providers to leverage individual's existing learning capacities to improve their cognitive health and well-being.

Therapeutic potential of gamma entrainment using sensory stimulation for cognitive symptoms associated with schizophrenia

Schizophrenia is a complex neuropsychiatric disorder with significant morbidity. Treatment options that address the spectrum of symptoms are limited, highlighting the need for innovative therapeutic approaches. Gamma Entrainment Using Sensory Stimulation (GENUS) is an emerging treatment for neuropsychiatric disorders that uses sensory stimulation to entrain impaired oscillatory network activity and restore brain function. Aberrant oscillatory activity often underlies the symptoms experienced by patients with schizophrenia. We propose that GENUS has therapeutic potential for schizophrenia. This paper reviews the current status of schizophrenia treatment and explores the use of sensory stimulation as an adjunctive treatment, specifically through gamma entrainment. Impaired gamma frequency entrainment is observed in patients, particularly in response to auditory and visual stimuli. Thus, sensory stimulation, such as music listening, may have therapeutic potential for individuals with schizophrenia. GENUS holds novel therapeutic potential to improve the lives of individuals with schizophrenia, but further research is required to determine the efficacy of GENUS, optimize its delivery and therapeutic window, and develop strategies for its implementation in specific patient populations.

The Less Things Change, the More They Remain the Same: Impaired Neural Plasticity as a Critical Target for Drug Development in Neuropsychiatry

Neuropsychiatric disability is related to reduced ability to change in response to clinical interventions, e.g., plasticity. Study of biomarkers and interventional strategies for plasticity, however, are sparse. In this chapter, we focus on the serial frequency discrimination task (SFDT), which is sensitive to impairments in early auditory processing (EAP) and auditory learning and has been most thoroughly studied in dyslexia and schizophrenia. In the SFDT, participants are presented with repeated paired tones ("reference" and "test") and indicate which tone is higher in pitch. Plasticity during the SFDT is critically dependent upon interactions between prefrontal "cognitive control" regions, and lower-level perceptual and motor regions that may be detected using both fMRI and time-frequency event-related potential (TF-ERP) approaches. Additionally, interactions between the cortex and striatum give insights into glutamate/dopamine interaction mechanisms. The SFDT task has been utilized in the development of N-methyl-D-aspartate receptor (NMDAR) targeted medications, which significantly modulate sensory and premotor neurophysiological activity. Deficits in pitch processing play a critical role in impaired neuro- and social cognitive function in schizophrenia and may contribute to similar impairments in dyslexia. Thus, the SFDT may be ideal for development of treatments aimed at amelioration of neuro- and social cognitive deficits across neuropsychiatric disorders.

Psychometric validation and clinical correlates of an experiential foraging task

Measuring the function of decision-making systems is a central goal of computational psychiatry. Individual measures of decisional function could be used to describe neurocognitive profiles that underpin psychopathology and offer insights into deficits that are shared across traditional diagnostic classes. However, there are few demonstrably reliable and mechanistically relevant metrics of decision making that can accurately capture the complex overlapping domains of cognition whilst also quantifying the heterogeneity of function between individuals. The WebSurf task is a reverse-translational human experiential foraging paradigm which indexes naturalistic and clinically relevant decision-making. To determine its potential clinical utility, we examined the psychometric properties and clinical correlates of behavioural parameters extracted from WebSurf in an initial exploratory experiment and a pre-registered validation experiment. Behaviour was stable over repeated administrations of the task, as were individual differences. The ability to measure decision making consistently supports the potential utility of the task in predicting an individual's propensity for response to psychiatric treatment, in evaluating clinical change during treatment, and in defining neurocognitive profiles that relate to psychopathology. Specific aspects of WebSurf behaviour also correlate with anhedonic and externalising symptoms. Importantly, these behavioural parameters may measure dimensions of psychological variance that are not captured by traditional rating scales. WebSurf and related paradigms might therefore be useful platforms for computational approaches to precision psychiatry.

Assessing Trial-to-Trial Variability in Auditory ERPs in Autism and Schizophrenia

Sensory abnormalities are characteristic of autism and schizophrenia. In autism, greater trial-to-trial variability (TTV) in sensory neural responses suggest that the system is more unstable. However, these findings have only been identified in the amplitude and not in the timing of neural responses, and have not been fully explored in schizophrenia. TTV in event-related potential amplitudes and inter-trial coherence (ITC) were assessed in the auditory mismatch negativity (MMN) in autism, schizophrenia, and controls. MMN was largest in autism and smallest in schizophrenia, and TTV was greater in autism and schizophrenia compared to controls. There were no differences in ITC. Greater TTV appears to be characteristic of both autism and schizophrenia, implicating several neural mechanisms that could underlie sensory instability.

The Effects of Remote Cognitive Training Combined With a Mobile App Intervention on Psychosis: Double-Blind Randomized Controlled Trial

BACKGROUND

Impairments in cognition and motivation are core features of psychosis and strong predictors of social and occupational functioning. Accumulating evidence indicates that cognitive deficits in psychosis can be improved by computer-based cognitive training programs; however, barriers include access and adherence to cognitive training exercises. Limited evidence-based methods have been established to enhance motivated behavior. In this study, we tested the effects of web-based targeted cognitive and social cognitive training (TCT) delivered in conjunction with an innovative digital smartphone app called Personalized Real-Time Intervention for Motivational Enhancement (PRIME). The PRIME app provides users with a motivational coach to set personalized goals and secure social networking for peer support.

OBJECTIVE

This study investigated whether deficits in cognition and motivation in people with a psychosis spectrum disorder (N=100) can be successfully addressed with 30 hours of TCT+PRIME as compared with 30 hours of a computer games control condition (CG) plus PRIME (CG+PRIME). Here, we describe our study procedures, the feasibility and acceptability of the intervention, and the results on all primary outcomes.

METHODS

In this double-blind randomized controlled trial, English-speaking participants completed all cognitive training, PRIME activities, and assessments remotely. Participants completed a diagnostic interview and remote cognitive, clinical, and self-report measures at baseline, posttraining, and at a 6-month follow-up.

RESULTS

This study included participants from 27 states across the United States and 8 countries worldwide. The study population was 58% (58/100) female, with a mean age of 33.77 (SD 10.70) years. On average, participants completed more than half of the cognitive training regimen (mean 18.58, SD 12.47 hours of training), and logged into the PRIME app 4.71 (SD 1.58) times per week. The attrition rate of 22% (22/100) was lower than that reported in our previous studies on remote cognitive training. The total sample showed significant gains in global cognition (P=.03) and attention (P<.001). The TCT+PRIME participants showed significantly greater gains in emotion recognition (P<.001) and global cognition at the trend level (P=.09), although this was not statistically significant, relative to the CG+PRIME participants. The total sample also showed significant improvements on multiple indices of motivation (P=.02-0.05), in depression (P=.04), in positive symptoms (P=.04), and in negative symptoms at a trend level (P=.09), although this was not statistically significant. Satisfaction with the PRIME app was rated at 7.74 (SD 2.05) on a scale of 1 to 10, with higher values indicating more satisfaction.

CONCLUSIONS

These results demonstrate the feasibility and acceptability of remote cognitive training combined with the PRIME app and that this intervention can improve cognition, motivation, and symptoms in individuals with psychosis. TCT+PRIME appeared more effective in improving emotion recognition and global cognition than CG+PRIME. Future analyses will test the relationship between hours of cognitive training completed; PRIME use; and changes in cognition, motivation, symptoms, and functioning.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02782442; https://clinicaltrials.gov/study/NCT02782442.

Efficacy of technology-based interventions in psychosis: a systematic review and network meta-analysis

BACKGROUND

Technology-based interventions (TBIs) are a useful approach when attempting to provide therapy to more patients with psychosis.

METHODS

Randomized controlled trials of outcomes of TBIs v. face-to-face interventions in psychosis were identified in a systematic search conducted in PubMed/Ovid MEDLINE. Data were extracted independently by two researchers, and standardized mean changes were pooled using a three-level model and network meta-analysis.

RESULTS

Fifty-eight studies were included. TBIs complementing treatment as usual (TAU) were generally superior to face-to-face interventions (g = 0.16, p ≤ 0.0001) and to specific outcomes, namely, neurocognition (g = 0.13, p ≤ 0.0001), functioning (g = 0.25, p = 0.006), and social cognition (g = 0.32, p ≤ 0.05). Based on the network meta-analysis, the effect of two TBIs differed significantly from zero; these were the TBIs cognitive training for the neurocognitive outcome [g = 0.16; 95% confidence interval (CI) 0.09-0.23] and cognitive behavioral therapy for quality of life (g = 1.27; 95% CI 0.46-2.08). The variables educational level, type of medication, frequency of the intervention, and contact during the intervention moderated the effectiveness of TBIs over face-to-face interventions in neurocognition and symptomatology.

CONCLUSIONS

TBIs are effective for the management of neurocognition, symptomatology, functioning, social cognition, and quality of life outcomes in patients with psychosis. The results of the network meta-analysis showed the efficacy of some TBIs for neurocognition, symptomatology, and quality of life. Therefore, TBIs should be considered a complement to TAU in patients with psychosis.

Cognitive Function in Patients at Different Stages of Treatment for Colorectal Cancer: A Comparative Cross-Sectional Study

OBJECTIVES

To compare subjective and objective cognitive functions among patients at the following three stages of treatment for colorectal cancer (CRC): new diagnosis (Group A), ≤2 years since chemotherapy completion (Group B), and >2 years since chemotherapy completion (Group C).

DATA SOURCES

A comparative cross-sectional approach was used in this study. The Functional Assessment of Cancer Therapy-Cognitive Function questionnaire and neuropsychological assessments were used to assess patients' subjective cognitive function, attention, memory, and executive functions. A total of 63 patients with stage I to III CRC were recruited from a medical center in northern Taiwan. We performed one-to-one-to-one propensity score matching to identify 36 individuals as eligible for this study. A generalized estimating equation was used to compare subjective and objective cognitive functions.

CONCLUSION

We observed no significant between-group differences in subjective cognitive function and objective performance in overall cognition and memory. Group B had significantly longer reaction time in attention and processing speed than did Group A. Adjuvant chemotherapy had significantly deleterious effects on attention and processing speed in patients with CRC. These cognitive symptoms last for approximately 2 years after the completion of chemotherapy.

IMPLICATIONS FOR NURSING PRACTICE

The early detection of cancer-related cognitive impairment is necessary for managing symptom distress. Future studies with a large sample size and longitudinal design may elucidate the trajectory of specific cognitive functions. Developing nursing interventions aimed at improving attention and executive function in patients with CRC are needed.

A combined exercise and cognitive training intervention induces fronto-cingulate cortical plasticity in first-episode psychosis patients

OBJECTIVE

Schizophrenia (SZ) is characterized by neurobiological and associated cognitive and functional deficits, including pronounced cortical thinning, that lead to acute and long-term functional impairment. Research with older adults supports the role of non-pharmacological interventions, such as exercise (E) and cognitive training (CT), for cognitive impairments. This literature influenced the development of combined CT&E treatments for individuals with SZ. However, the impact of longer combined treatment duration (6 months) on neuroanatomy has yet to be explored in patients in the early course of the illness. The impact of adding exercise to cognitive training for key brain regions associated with higher-order cognition was examined here using magnetic resonance imaging (MRI) in first-episode psychosis (FEP) patients.

METHODS

UCLA Aftercare Research Program patients with a recent first episode of schizophrenia were randomly assigned to either combined cognitive and exercise training (CT&E) (N = 20) or cognitive training alone (CT) (N = 17) intervention. Cortical thickness was measured longitudinally and analyzed for two regions of interest using FreeSurfer.

RESULTS

Compared to patients in the CT group, those in the CT&E group demonstrated an increase in cortical thickness within the left anterior cingulate cortex over the six-month treatment period (ACC: F(1, 35) = 4.666, P < .04). Directional tendencies were similar in the left dorsolateral prefrontal cortex (DLPFC: F(1,35) = 4.132, P < .05).

CONCLUSIONS

These findings suggest that exercise and cognitive training may synergistically increase fronto-cingulate cortical thickness to mitigate progressive neural atrophy in the early course of SZ. This combined intervention appears to be a valuable adjunct to standard pharmacologic treatment in FEP patients.

Auditory discrimination and frequency modulation learning in schizophrenia patients: amphetamine within-subject dose response and time course

BACKGROUND

Auditory frequency modulation learning ('auditory learning') is a key component of targeted cognitive training (TCT) for schizophrenia. TCT can be effective in enhancing neurocognition and function in schizophrenia, but such gains require significant time and effort and elude many patients.

METHODS

As a strategy to increase and/or accelerate TCT-induced clinical gains, we tested the dose- and time-course effects of the pro-attentional drug, amphetamine (AMPH; placebo, 2.5, 5 or 10 mg po; within-subject double-blind, order balanced) on auditory learning in schizophrenia patients [n = 32; M:F = 19:13; age 42.0 years (24-55)]. To understand predictors and/or mechanisms of AMPH-enhanced TCT, we also measured auditory fidelity (words-in-noise (WIN), quick speech-in-noise (QuickSIN)) and neurocognition (MATRICS comprehensive cognitive battery (MCCB)). Some measures were also acquired from age-matched healthy subjects (drug free; n = 10; M:F = 5:5).

RESULTS

Patients exhibited expected deficits in neurocognition. WIN and QuickSIN performance at low signal intensities was impaired in patients with low v. high MCCB attention/vigilance (A/V) scores; these deficits were corrected by AMPH, maximally at 2.5-5 mg (d's = 0.79-1.29). AMPH also enhanced auditory learning, with maximal effects at 5 mg (d = 0.93), and comparable effects 60 and 210 min post pill. 'Pro-learning' effects of AMPH and AMPH-induced gains in auditory fidelity were most evident in patients with low MCCB A/V scores.

CONCLUSIONS

These findings advance our understanding of the impact of pro-attentional interventions on auditory information processing and suggest dose- and time-course parameters for studies that assess the ability of AMPH to enhance the clinical benefits of TCT in schizophrenia patients.

Association between motivation and engagement with changes in cognition and symptoms after digital cognitive training in schizophrenia

BACKGROUND

Digital cognitive training can remediate cognitive deficits present in schizophrenia. However, limited motivation and engagement may impact adherence to training. Therefore, identifying factors that may enhance (facilitators) or decrease (barriers) engagement in digital cognitive training and possibly modulate its effects are of great clinical relevance.

METHODS

We measured cognition, symptom severity, motivation (semi-structured interview), and engagement (adapted Utrecht Work Engagement Scale - UWES) of 27 patients with schizophrenia after a 40-h digital cognitive training. The interview transcript quotes were coded and categorized into facilitators and barriers. Thereafter, we tested the association of motivation and engagement with changes in cognition and symptoms after training.

RESULTS

The facilitator 'good performance' and the barrier 'difficult exercise' were associated with larger gains in attention (p = 0.03) and reasoning and problem solving (p = 0.02), respectively. 'Poor performance' was associated with smaller gains in global cognition (p < 0.01), attention (p = 0.03), and working memory (p = 0.02). The facilitator 'welcoming setting' was associated with larger reductions in the negative (p = 0.01) and total (p = 0.01) symptoms measured by the Positive and Negative Syndrome Scale. The UWES engagement scale was associated with different facilitators and barriers that emerged from the interview, an indication of consistency among both qualitative and quantitative assessments.

DISCUSSION

Using a mixed quantitative and qualitative research design, we showed associations between motivation and engagement and the response to digital cognitive training in schizophrenia. Facilitators and barriers were associated with engagement, gains in cognition, and reduced symptoms after the intervention, providing insights on how to increase engagement in the digital cognitive training delivered to subjects with schizophrenia.

Cognitive Rehabilitation in Schizophrenia-Associated Cognitive Impairment: A Review

Patients suffering from schizophrenia often experience cognitive disturbances. Cognitive rehabilitation-computerized or non-computerized-is widely known as an alternative way to enhance cognitive functioning in patients with schizophrenia. The aim of the present review was to examine the role of cognitive rehabilitation (both computerized and non-computerized) for the alleviation of cognitive impairment in schizophrenia patients. Fourteen relative studies were examined and included in the present review. The results revealed that both computerized and non-computerized cognitive rehabilitation could enhance cognitive functioning and more specifically memory, attention, executive functioning, processing speed and in a few cases, even non-cognitive impairments, such as other schizophrenia symptoms. The present results support the efficacy of cognitive rehabilitation in schizophrenia patients, regardless of whether it is computerized or non-computerized. As the randomized control trials (RCTs) are limited in number, there is urgent need for more RCTs and longitudinal studies combining different kinds of interventions, as well as systematic reviews and meta-analyses, in order to further investigate and confirm the current results.

Magnocellular and parvocellular contributions to brain network dysfunction during learning and memory: Implications for schizophrenia

Memory deficits are core features of schizophrenia, and a central aim in biological psychiatry is to identify the etiology of these deficits. Scrutiny is naturally focused on the dorsolateral prefrontal cortex and the hippocampal cortices, given these structures' roles in memory and learning. The fronto-hippocampal framework is valuable but restrictive. Network-based underpinnings of learning and memory are substantially diverse and include interactions between hetero-modal and early sensory networks. Thus, a loss of fidelity in sensory information may impact memorial and cognitive processing in higher-order brain sub-networks, becoming a sensory source for learning and memory deficits. In this overview, we suggest that impairments in magno- and parvo-cellular visual pathways result in degraded inputs to core learning and memory networks. The ascending cascade of aberrant neural events significantly contributes to learning and memory deficits in schizophrenia. We outline the network bases of these effects, and suggest that any network perspectives of dysfunction in schizophrenia must assess the impact of impaired perceptual contributions. Finally, we speculate on how this framework enriches the space of biomarkers and expands intervention strategies to ameliorate this prototypical disconnection syndrome.

Can neuroimaging-based biomarkers predict response to cognitive remediation in patients with psychosis? A state-of-the-art review

BACKGROUND

Cognitive Remediation (CR) is designed to halt the pathological neural systems that characterize major psychotic disorders (MPD), and its main objective is to improve cognitive functioning. The magnitude of CR-induced cognitive gains greatly varies across patients with MPD, with up to 40% of patients not showing gains in global cognitive performance. This is likely due to the high degree of heterogeneity in neural activation patterns underlying cognitive endophenotypes, and to inter-individual differences in neuroplastic potential, cortical organization and interaction between brain systems in response to learning. Here, we review studies that used neuroimaging to investigate which biomarkers could potentially serve as predictors of treatment response to CR in MPD.

METHODS

This systematic review followed the PRISMA guidelines. An electronic database search (Embase, Elsevier; Scopus, PsycINFO, APA; PubMed, APA) was conducted in March 2021. peer-reviewed, English-language studies were included if they reported data for adults aged 18+ with MPD, reported findings from randomized controlled trials or single-arm trials of CR; and presented neuroimaging data.

RESULTS

Sixteen studies were included and eight neuroimaging-based biomarkers were identified. Auditory mismatch negativity (3 studies), auditory steady-state response (1), gray matter morphology (3), white matter microstructure (1), and task-based fMRI (7) can predict response to CR. Efference copy corollary/discharge, resting state, and thalamo-cortical connectivity (1) require further research prior to being implemented.

CONCLUSIONS

Translational research on neuroimaging-based biomarkers can help elucidate the mechanisms by which CR influences the brain's functional architecture, better characterize psychotic subpopulations, and ultimately deliver CR that is optimized and personalized.

The viability of the frequency following response characteristics for use as biomarkers of cognitive therapeutics in schizophrenia

Deficits in early auditory information processing contribute to cognitive and psychosocial disability; this has prompted development of interventions that target low-level auditory processing, which may alleviate these disabilities. The frequency following response (FFR) is a constellation of event-related potential and frequency characteristics that reflect the processing of acoustic stimuli at the level of the brainstem and ascending portions of the auditory pathway. While FFR is a promising candidate biomarker of response to auditory-based cognitive training interventions, the psychometric properties of FFR in schizophrenia patients have not been studied. Here we assessed the psychometric reliability and magnitude of group differences across 18 different FFR parameters to determine which of these parameters demonstrate adequate internal consistency. Electroencephalography from 40 schizophrenia patients and 40 nonpsychiatric comparison subjects was recorded during rapid presentation of an auditory speech stimulus (6000 trials). Patients showed normal response amplitudes but longer latencies for most FFR peaks and lower signal-to-noise ratios (SNRs) than healthy subjects. Analysis of amplitude and latency estimates of peaks, however, indicated a need for a substantial increase in task length to obtain internal consistency estimates above 0.80. In contrast, excellent internal consistency (>0.95) was shown for FFR sustained responses. Only SNR scores reflecting the FFR sustained response yielded significant group differences and excellent internal consistency, suggesting that this measure is a viable candidate for use in clinical treatment studies. The present study highlights the use of internal consistency estimates to select FFR characteristics for use in future intervention studies interested in individual differences among patients.

Durable Cognitive Gains and Symptom Improvement Are Observed in Individuals With Recent-Onset Schizophrenia 6 Months After a Randomized Trial of Auditory Training Completed Remotely

OBJECTIVE

Cognitive impairment in schizophrenia predicts functional outcomes and is largely unresponsive to pharmacology or psychotherapy; it is thus a critical unmet treatment need. This article presents the impact of remotely completed, intensive, targeted auditory training (AT) vs control condition computer games (CG) in a double-blind randomized trial in young adults with recent-onset schizophrenia.

METHOD

Participants (N = 147) were assessed for cognition, symptoms, and functioning at baseline, post-intervention, and at 6-month follow-up. All participants were provided with laptop computers and were instructed to complete 40 hours remotely of training or computer games. An intent-to-treat analysis (N = 145) was performed using linear mixed models with time modeled as a continuous variable. Planned contrasts tested the change from baseline to post-training, baseline to 6-month follow-up, and post-training to 6-month follow-up.

RESULTS

Global Cognition, which had improved in the AT group relative to the CG group at post-training, showed durable gains at 6-month follow-up in an omnibus group-by-time interaction test (F(1,179) = 4.80, P = .030), as did Problem-Solving (F(1,179) = 5.13, P = .025), and Speed of Processing improved at trend level significance (F(1,170) = 3.80, P = .053). Furthermore, the AT group showed significantly greater improvement than the CG group in positive symptoms (F(1,179) = 4.06, P = .045).

CONCLUSIONS

These results provide the first evidence of durable cognitive gains and symptom improvement at follow-up of cognitive training (CT) in early schizophrenia completed independently and remotely. While functioning did not show significant improvement, these findings suggest that intensive targeted CT of auditory processing is a promising component of early intervention to promote recovery from psychosis.

The effects of neuroplasticity-based auditory information processing remediation in adults with chronic traumatic brain injury

BACKGROUND

Adults with chronic traumatic brain injury (TBI) may experience long-term deficits in multiple cognitive domains. Higher-order functions, such as verbal memory, are impacted by deficits in the ability to acquire verbal information.

OBJECTIVE

This study investigated the effects of a neuroplasticity-based computerized cognitive remediation program for auditory information processing in adults with a chronic TBI.

METHODS

Forty-eight adults with TBI were randomly assigned to an intervention or control group. Both groups underwent a neuropsychological assessment at baseline and post-training. The Intervention group received 40 one-hour cognitive training sessions with the Brain Fitness Program.

RESULTS

The intervention group improved in performance on measures of the Woodcock-Johnson-III Understanding Directions subtest and Trail Making Test Part-A. They also reported improvement on the cognitive domain of the Cognitive Self-Report Questionnaire.

CONCLUSIONS

The present study demonstrated that a neuroplasticity-based computerized cognitive remediation program may improve objective and subjective cognitive function in adults with TBI several years post-injury.

Multivariate pattern analysis of brain structure predicts functional outcome after auditory-based cognitive training interventions

Cognitive gains following cognitive training interventions are associated with improved functioning in people with schizophrenia (SCZ). However, considerable inter-individual variability is observed. Here, we evaluate the sensitivity of brain structural features to predict functional response to auditory-based cognitive training (ABCT) at a single-subject level. We employed whole-brain multivariate pattern analysis with support vector machine (SVM) modeling to identify gray matter (GM) patterns that predicted higher vs. lower functioning after 40 h of ABCT at the single-subject level in SCZ patients. The generalization capacity of the SVM model was evaluated by applying the original model through an out-of-sample cross-validation analysis to unseen SCZ patients from an independent validation sample who underwent 50 h of ABCT. The whole-brain GM volume-based pattern classification predicted higher vs. lower functioning at follow-up with a balanced accuracy (BAC) of 69.4% (sensitivity 72.2%, specificity 66.7%) as determined by nested cross-validation. The neuroanatomical model was generalizable to an independent cohort with a BAC of 62.1% (sensitivity 90.9%, specificity 33.3%). In particular, greater baseline GM volumes in regions within superior temporal gyrus, thalamus, anterior cingulate, and cerebellum predicted improved functioning at the single-subject level following ABCT in SCZ participants. The present findings provide a structural MRI fingerprint associated with preserved GM volumes at a single baseline timepoint, which predicted improved functioning following an ABCT intervention, and serve as a model for how to facilitate precision clinical therapies for SCZ based on imaging data, operating at the single-subject level.

Initial performance predicts improvements in computerized cognitive training: Evidence from a selective attention task

Computerized cognitive training (CCT) has been found to improve a range of skills such as attention, working memory, inhibition control, and decision making. However, the relationship between the initial performance, amount of improvement, time constant, and asymptotic performance level in CCT is still unclear. In the current study, we performed selective attention training on college students and addressed this issue by mathematically modeling the learning curve with an exponential function. Twenty-nine students completed approximately 10 days of CCT. Presentation time served as the dependent variable and was measured by three-down/one-up adaptive algorithms. We fitted an exponential function to the estimated block thresholds during CCT and obtained three learning parameters (amount of improvement, time constant, and asymptotic performance level) for all subjects. The initial performance was defined by the sum of the amount of improvement and the asymptotic performance level. Pearson correlation analyses were conducted between the initial performance and the three leaning parameters. The initial performance was positively correlated with the amount of improvement and asymptotic performance level, but was negatively correlated with the time constant. The time constant was negatively correlated with the amount of improvement and asymptotic performance level. Poorer initial performance was linked to a larger amount of improvement, shorter time constant, and higher asymptotic threshold, which supported the compensation account. Our results may help improve the present understanding of the nature of the CCT process and demonstrate the advantages of using a customized training protocol to enhance the efficiency of cognitive training in practical applications.

Use of cognitive event-related potentials in the management of psychiatric disorders: Towards an individual follow-up and multi-component clinical approach

Relapse prevention remains a major challenge in psychiatry, thus indicating that the established treatment methods combining psychotherapy with neuropharmacological interventions are not entirely effective. In recent years, several intervention strategies have been devised that are aimed at improving psychiatric treatment by providing a complementary set of add-on tools that can be used by clinicians to improve current patient assessment. Among these, cognitive event-related potentials (ERPs) have been indexed as valuable biomarkers of the pathophysiological mechanisms of various mental illnesses. However, despite decades of research, their clinical utility is still controversial and a matter of debate. In this opinion review, I present the main arguments supporting the use of cognitive ERPs in the management of psychiatric disorders, stressing why it is currently still not the case despite the vast number of ERP studies to date. I also propose a clinically-oriented suitable way in which this technique could - in my opinion - be effectively incorporated into individual patient care by promotion of the use of individual ERP test-retest sessions and the use of a multi-component approach.

Video games for people with schizophrenia

BACKGROUND

Commercial video games are a vastly popular form of recreational activity. Whilst concerns persist regarding possible negative effects of video games, they have been suggested to provide cognitive benefits to users. They are also frequently employed as control interventions in comparisons of more complex cognitive or psychological interventions. If independently effective, video games - being both engaging and relatively inexpensive - could provide a much more cost-effective add-on intervention to standard treatment when compared to costly, cognitive interventions.

OBJECTIVES

To review the effects of video games (alone or as an additional intervention) compared to standard care alone or other interventions including, but not limited to, cognitive remediation or cognitive behavioural therapy for people with schizophrenia or schizophrenia-like illnesses.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group's Study-Based Register of Trials (March 2017, August 2018, August 2019).

SELECTION CRITERIA

Randomised controlled trials focusing on video games for people with schizophrenia or schizophrenia-like illnesses.

DATA COLLECTION AND ANALYSIS

Review authors extracted data independently. For binary outcomes we calculated risk ratio (RR) with its 95% confidence interval (CI) on an intention-to-treat basis. For continuous data we calculated the mean difference (MD) between groups and its CI. We employed a fixed-effect model for analyses. We assessed risk of bias for the included studies and created a 'Summary of findings' table using GRADE.

MAIN RESULTS

This review includes seven trials conducted between 2009 and 2018 (total = 468 participants, range 32 to 121). Study duration varied from six weeks to twelve weeks. All interventions in the included trials were given in addition to standard care, including prescribed medication. In trials video games tend to be the control for testing efficacy of complex, cognitive therapies; only two small trials evaluated commercial video games as the intervention. We categorised video game interventions into 'non-exergame' (played statically) and 'exergame' (the players use bodily movements to control the game). Our main outcomes of interest were clinically important changes in: general functioning, cognitive functioning, social functioning, mental state, quality of life, and physical fitness as well as clinically important adverse effects. We found no clear difference between non-exergames and cognitive remediation in general functioning scores (Strauss Carpenter Outcome Scale) (MD 0.42, 95% CI -0.62 to 1.46; participants = 86; studies = 1, very low-quality evidence) or social functioning scores (Specific Levels of Functioning Scale) (MD -3.13, 95% CI -40.17 to 33.91; participants = 53; studies = 1, very low-quality evidence). There was a clear difference favouring cognitive remediation for cognitive functioning (improved on at least one domain of MATRICS Consensus Cognitive Battery Test) (RR 0.58, 95% CI 0.34 to 0.99; participants = 42; studies = 1, low-quality evidence). For mental state, Positive and Negative Syndrome Scale (PANSS) overall scores showed no clear difference between treatment groups (MD 0.20, 95% CI -3.89 to 4.28; participants = 269; studies = 4, low-quality evidence). Quality of life ratings (Quality of Life Scale) similarly showed no clear intergroup difference (MD 0.01, 95% CI -0.40 to 0.42; participants = 87; studies = 1, very low-quality evidence). Adverse effects were not reported; we chose leaving the study early as a proxy measure. The attrition rate by end of treatment was similar between treatment groups (RR 0.96, 95% CI 0.87 to 1.06; participants = 395; studies = 5, low-quality evidence). One small trial compared exergames with standard care, but few outcomes were reported. No clear difference between interventions was seen for cognitive functioning (measured by MATRICS Consensus Cognitive Battery Test) (MD 2.90, 95% CI -1.27 to 7.07; participants = 33; studies = 1, low-quality evidence), however a benefit in favour of exergames was found for average change in physical fitness (aerobic fitness) (MD 3.82, 95% CI 1.75 to 5.89; participants = 33; studies = 1, low-quality evidence). Adverse effects were not reported; we chose leaving the study early as a proxy measure. The attrition rate by end of treatment was similar between treatment groups (RR 1.06, 95% CI 0.75 to 1.51; participants = 33; studies = 1). Another small trial compared exergames with non-exergames. Only one of our main outcomes was reported - physical fitness, which was measured by average time taken to walk 3 metres. No clear intergroup difference was identified at six-week follow-up (MD -0.50, 95% CI -1.17 to 0.17; participants = 28; studies = 1, very low-quality evidence). No trials reported adverse effects. We chose leaving the study early as a proxy outcome.

AUTHORS' CONCLUSIONS

Our results suggest that non-exergames may have a less beneficial effect on cognitive functioning than cognitive remediation, but have comparable effects for all other outcomes. These data are from a small number of trials, and the evidence is graded as of low or very low quality and is very likely to change with more data. It is difficult to currently establish if the more sophisticated cognitive approaches do any more good - or harm - than 'static' video games for people with schizophrenia. Where players use bodily movements to control the game (exergames), there is very limited evidence suggesting a possible benefit of exergames compared to standard care in terms of cognitive functioning and aerobic fitness. However, this finding must be replicated in trials with a larger sample size and that are conducted over a longer time frame. We cannot draw any firm conclusions regarding the effects of video games until more high-quality evidence is available. There are ongoing studies that may provide helpful data in the near future.

Gamma oscillations predict pro-cognitive and clinical response to auditory-based cognitive training in schizophrenia

Cognitive impairments are pervasive and disabling features of schizophrenia. Targeted cognitive training (TCT) is a "bottom-up" cognitive remediation intervention with efficacy for neurocognitive outcomes in schizophrenia, yet individual responses are variable. Gamma oscillatory measures are leading candidate biomarkers in the development of biologically informed pro-cognitive therapeutics. Forty-two schizophrenia patients were recruited from a long-term residential treatment facility. Participants were randomized to receive either 1 h of cognitive training (TCT, n = 21) or computer games (TAU, n = 21). All participants received standard-of-care treatment; the TCT group additionally completed 30 h of cognitive training. The auditory steady-state response paradigm was used to elicit gamma oscillatory power and synchrony during electroencephalogram recordings. Detailed clinical and cognitive assessments were collected at baseline and after completion of the study. Baseline gamma power predicted cognitive gains after a full course of TCT (MCCB, R² = 0.31). A change in gamma power after 1-h TCT exposure predicted improvement in both positive (SAPS, R² = 0.40) and negative (SANS, R² = 0.30) symptoms. These relationships were not observed in the TAU group (MCCB, SAPS, and SANS, all R² < 0.06). The results indicate that the capacity to support gamma oscillations, as well as the plasticity of the underlying ASSR circuitry after acute exposure to 1 h of TCT, reflect neural mechanisms underlying the efficacy of TCT, and may be used to predict individualized treatment outcomes. These findings suggest that gamma oscillatory biomarkers applied within the context of experimental medicine designs can be used to personalize individual treatment options for pro-cognitive interventions in patients with schizophrenia.

Auditory-Based Cognitive Training Drives Short- and Long-Term Plasticity in Cortical Networks in Schizophrenia

Schizophrenia patients have widespread deficits in neurocognitive functioning linked to underlying abnormalities in gamma oscillations that are readily measured by the 40 Hz auditory steady-state response (ASSR). Emerging interventions such as auditory-based targeted cognitive training (TCT) improve neurocognitive function in patients. While acute ASSR changes after 1 hour of TCT predict clinical and cognitive gains after a 30-hour course of TCT, the neural substrates of underlying short- and long-term TCT interventions are unknown. To determine the neural substrates underlying TCT-associated ASSR changes, a novel data analysis method was applied to assess the effective connectivity of gamma-band ASSR among estimated cortical sources. In this study, schizophrenia patients (N = 52) were randomized to receive either a treatment as usual (TAU; N = 22) or TAU augmented with TCT (N = 30). EEG recordings were obtained immediately before (T0) and after 1 hour of either computer games (TAU) or cognitive training (TCT; T1), and at 65 ± 15 days (mean ± SD) post-randomization (T2). Results showed increased connectivity from the left ventral middle cingulate gyrus to the left posterior cingulate gyrus, accompanied by decreased connectivity from the left Rolandic operculum (a region that includes auditory cortex) to the right ventral middle cingulate gyrus after 1 hour of TCT. After 30 hours, decreased connectivity from the frontal cortex to a region near the calcarine sulcus were detected. Auditory-based cognitive training drives short- and long-term plasticity in cortical network functioning in schizophrenia patients. These findings may help us understand the mechanisms underlying cognitive training effects in schizophrenia patients and enhance the development of pro-cognitive therapeutics.

Cognitive remediation plus standard treatment versus standard treatment alone for individuals at ultra-high risk of developing psychosis: Results of the FOCUS randomised clinical trial

BACKGROUND

Individuals at ultra-high risk (UHR) for psychosis have significant cognitive deficits that can impede functional recovery. Applying cognitive remediation (CR) before the onset of frank psychosis may improve the cognitive and functional prognosis of UHR individuals, however, little is known about the feasibility and efficacy of CR for this population.

METHODS

In this randomised, clinical trial 146 individuals at UHR for psychosis aged 18-40 years were randomly assigned to treatment as usual (TAU) or TAU plus cognitive remediation. The CR targeted neurocognitive and social cognitive remediation. Assessments were carried out at 6- and 12-months post baseline.

RESULTS

A total of 73 UHR individuals were assigned to TAU and 73 assigned to TAU + cognitive remediation. Compared to the control group, cognitive remediation did not result in significant improvement on the primary outcome; the Brief Assessment of Cognition in Schizophrenia composite score at 6-month follow-up (b = -0.125, 95%CI: -0.23 to 0.172, p = 0.41). Nor did the intervention improve secondary outcomes in clinical symptoms or functioning. Exploratory analyses found emotion recognition latencies to be significantly more reduced in the intervention group at 6-months. At 12-months, the intervention group exhibited significantly better performance on two measures of executive function and visual memory.

CONCLUSION

The 20-session treatment protocol was not well received in the UHR group, and unsurprisingly global measures did not improve. The benefit found in isolated neuro- and social cognitive measures after even a few sessions points to a potential for cognitive malleability if people can be engaged sufficiently to practice the skills. Trial registration ClinicalTrial.gov identifier: NCT02098408.

Auditory versus visual neuroscience-informed cognitive training in schizophrenia: Effects on cognition, symptoms and quality of life

BACKGROUND

Cognitive impairments are related to deficits in primary auditory and visual sensory processes in schizophrenia. These impairments can be remediated by neuroscience-informed computerized cognitive trainings that target auditory and visual processes. However, it is not clear which modality results in greater improvements in cognition, symptoms and quality of life. We aimed to investigate the impact of training auditory versus visual cognitive processes in global cognition in patients with schizophrenia.

METHODS

Seventy-nine schizophrenia participants were randomly assigned to either 40 h of auditory or visual computerized training. Auditory and visual exercises were chosen to be dynamically equivalent and difficulties increased progressively during the training. We evaluated cognition, symptoms and quality of life before, after 20 h, and after 40 h of training. ClinicalTrials.gov (1R03TW009002-01).

RESULTS

Participants who received the visual training showed significant improvements in global cognition compared to the auditory training group. The visual training significantly improved attention and reasoning and problem-solving, while the auditory training improved reasoning and problem-solving only. Schizophrenia symptoms improved after training in both groups, whereas quality of life remained unchanged. Interestingly, there was a significant and positive correlation between improvements in attention and symptoms in the visual training group.

CONCLUSIONS

We conclude that the visual training and the auditory training are differentially efficient at remediating cognitive deficits and symptoms of clinically stable schizophrenia patients. Ongoing follow-up of participants will evaluate the durability of training effects on cognition and symptoms, as well as the potential impact on quality of life over time.

Clinical and methodological considerations for psychological treatment of cognitive impairment in major depressive disorder

BACKGROUND

Cognitive impairment is considered a core feature of major depressive disorder (MDD) and research into psychological treatments aiming to address cognitive impairment are gaining momentum. Compared with the well-established research base of cognitive treatment trials in schizophrenia, including meta-analyses, mood disorder research is much more preliminary.

AIMS

To focus on identifying the important factors to consider in developing larger-scale psychological treatment trials targeting cognitive impairment in mood disorders. Trial design recommendations have been published for cognitive treatment trials in bipolar disorder.

METHOD

An in-depth discussion of methodological considerations in the development of cognitive treatment trials for MDD.

RESULTS

Methodological considerations include: screening for, and defining, cognitive impairment; mood state when cognitive intervention begins; medication monitoring during cognitive interventions; use of concomitant therapy; level of therapist involvement; duration and dose of treatment; choice of specific cognitive training exercises; home practice; improving adherence; appropriate comparison therapies in clinical trials; and choice of primary outcomes.

CONCLUSIONS

As well as guidance for clinical trial development, this review may be helpful for clinicians wanting to provide cognitive interventions for individuals with MDD.

Augmenting Computerized Cognitive Training With Vortioxetine for Age-Related Cognitive Decline: A Randomized Controlled Trial

OBJECTIVE

Age-related cognitive decline, the deterioration in functions such as memory and executive function, is faced by most older adults and affects function and quality of life. No approved treatments exist for age-related cognitive decline. Computerized cognitive training has been shown to provide consistent albeit modest improvements in cognitive function as measured by neuropsychological testing. Vortioxetine, an antidepressant medication, has putative procognitive and proneuroplastic properties and therefore may be able to augment cognitive training. In this placebo-controlled study, the authors tested the cognitive benefits of vortioxetine added to cognitive training for adults age 65 or older with age-related cognitive decline.

METHODS

After a 2-week lead-in period of cognitive training, 100 participants were randomly assigned to receive either vortioxetine or placebo in addition to cognitive training for 26 weeks. The primary outcome measure was global cognitive performance, assessed by the NIH Toolbox Cognition Battery Fluid Cognition Composite. The secondary outcome measure was functional cognition, assessed by the UCSD Performance-Based Skills Assessment. All participants received motivational messaging and support from study staff to maximize adherence to the training.

RESULTS

Participants who received vortioxetine with cognitive training showed a greater increase in global cognitive performance compared with those who received placebo with cognitive training. This separation was significant at week 12 but not at other assessment time points. Both groups showed improvement in the secondary outcome measure of functional cognition, with no significant difference between groups.

CONCLUSIONS

Vortioxetine may be beneficial for age-related cognitive decline when combined with cognitive training. These findings provide new treatment directions for combating cognitive decline in older adults.

The Visual Word Form Area compensates for auditory working memory dysfunction in schizophrenia

Auditory working memory impairments feature prominently in schizophrenia. However, the existence of altered and perhaps compensatory neural dynamics, sub-serving auditory working memory, remains largely unexplored. We compared the dynamics of induced high gamma power (iHGP) across cortex in humans during speech-sound working memory in individuals with schizophrenia (SZ) and healthy comparison subjects (HC) using magnetoencephalography (MEG). SZ showed similar task performance to HC while utilizing different brain regions. During encoding of speech sounds, SZ lacked the correlation of iHGP with task performance in posterior superior temporal gyrus (STGp) that was observed in healthy subjects. Instead, SZ recruited the visual word form area (VWFA) during both stimulus encoding and response preparation. Importantly, VWFA activity during encoding correlated with the magnitude of SZ hallucinations, task performance and an independent measure of verbal working memory. These findings suggest that VWFA plasticity is harnessed to compensate for STGp dysfunction in schizophrenia patients with hallucinations.

Six month durability of targeted cognitive training supplemented with social cognition exercises in schizophrenia

Background

Deficits in cognition, social cognition, and motivation are significant predictors of poor functional outcomes in schizophrenia. Evidence of durable benefit following social cognitive training is limited. We previously reported the effects of 70 h of targeted cognitive training supplemented with social cognitive exercises (TCT + SCT) verses targeted cognitive training alone (TCT). Here, we report the effects six months after training.

Methods

111 participants with schizophrenia spectrum disorders were randomly assigned to TCT + SCT or TCT-only. Six months after training, thirty-four subjects (18 TCT + SCT, 16 TCT-only) were assessed on cognition, social cognition, reward processing, symptoms, and functioning. Intent to treat analyses was used to test the durability of gains, and the association of gains with improvements in functioning and reward processing were tested.

Results

Both groups showed durable improvements in multiple cognitive domains, symptoms, and functional capacity. Gains in global cognition were significantly associated with gains in functional capacity. In the TCT + SCT group, participants showed durable improvements in prosody identification and reward processing, relative to the TCT-only group. Gains in reward processing in the TCT + SCT group were significantly associated with improvements in social functioning.

Conclusions

Both TCT + SCT and TCT-only result in durable improvements in cognition, symptoms, and functional capacity six months post-intervention. Supplementing TCT with social cognitive training offers greater and enduring benefits in prosody identification and reward processing. These results suggest that novel cognitive training approaches that integrate social cognitive exercises may lead to greater improvements in reward processing and functioning in individuals with schizophrenia.

Specificity and Durability of Changes in Auditory Processing Efficiency After Targeted Cognitive Training in Individuals With Recent-Onset Psychosis

BACKGROUND

We previously demonstrated that the high heterogeneity of response to computerized Auditory Training (AT) in psychosis can be ascribed to individual differences in sensory processing efficiency and neural plasticity. In particular, we showed that Auditory Processing Speed (APS) serves as a behavioral measure of target engagement, with faster speed predicting greater transfer effects to untrained cognitive domains. Here, we investigate whether the ability of APS to function as a proxy for target engagement is unique to AT, or if it applies to other training interventions, such as Executive Functioning Training (EFT). Additionally, we examine whether changes in APS are durable after these two forms of training.

METHODS

One hundred and twenty-five participants with Recent Onset Psychosis (ROP) were randomized to AT (n = 66) and EFT (n = 59), respectively. APS was captured at baseline, after treatment, and at 6-month follow-up. Mixed models repeated measures analysis with restricted maximum likelihood was used to examine whether training condition differentiated APS trajectories. Within-group correlational analyses were used to study the relationship between APS and performance improvements in each of the training exercises.

RESULTS

The two groups were matched for age, gender, education, and baseline APS. Participants showed high inter-individual variability in APS at each time point. The mixed model showed a significant effect of time (F = 5.99, p = .003) but not a significant group-by-time effect (F = .73, p = .48). This was driven by significant APS improvements AT patients after treatment (d = .75) that were maintained after 6 months (d = .63). Conversely, in EFT patients, APS improvements did not reach statistical significance after treatment (p = .33) or after 6 months (p = .24). In AT patients, baseline APS (but not APS change) highly predicted peak performance for each training exercise (all r's >.42).

CONCLUSIONS

Participant-specific speed in processing basic auditory stimuli greatly varies in ROP, and strongly influences the magnitude of response to auditory but not executive functioning training. Importantly, enhanced auditory processing efficiency persists 6 months after AT, suggesting the durability of neuroplasticity processes induced by this form of training. Future studies should aim to identify markers of target engagement and durability for cognitive training interventions that target sensory modalities beyond the auditory domain.

Intervention-specific patterns of cortical function plasticity during auditory encoding in people with schizophrenia

Schizophrenia is a neurocognitive illness characterized by behavioral and neural impairments in both early auditory processing and higher order verbal working memory. Previously we have shown intervention-specific cognitive performance improvements with computerized, targeted training of auditory processing (AT) when compared to a computer games (CG) control intervention that emphasized visual processing. To investigate spatiotemporal changes in patterns of neural activity specific to the AT intervention, the current study used magnetoencephalography (MEG) imaging to derive induced high gamma band oscillations (HGO) during auditory encoding, before and after 50 h (∼10 weeks) of exposure to either the AT or CG intervention. During stimulus encoding, AT intervention-specific changes in high gamma activity occurred in left middle frontal and left middle-superior temporal cortices. In contrast, CG intervention-specific changes were observed in right medial frontal and supramarginal gyri during stimulus encoding, and in bilateral temporal cortices during response preparation. These data reveal that, in schizophrenia, intensive exposure to either training of auditory processing or exposure to visuospatial activities produces significant but complementary patterns of cortical function plasticity within a distributed fronto-temporal network. These results underscore the importance of delineating the specific neuroplastic effects of targeted behavioral interventions to ensure desired neurophysiological changes and avoid unintended consequences on neural system functioning.

Oscillatory biomarkers of early auditory information processing predict cognitive gains following targeted cognitive training in schizophrenia patients

Auditory-based targeted cognitive training (TCT) is an effective and well-validated intervention for the treatment of cognitive impairment in schizophrenia patients. Improvements in higher-order cognition, reductions in symptom severity, and increases in psychosocial functioning secondary to TCT are thought to be driven by "bottom-up" enhancement of early auditory information processing (EAIP). Despite strong evidence of efficacy at the group level, there is significant variability in response to TCT, with few well-delineated biomarkers for predicting individual benefit. EEG biomarkers of EAIP are indicators of early-treatment sensitivity that predict full-course TCT outcome; however, further characterization is necessary for biomarker-guided clinical trials. The current study examined baseline and early-treatment sensitivity (i.e., change from baseline after 1 h) in theta band oscillatory activity to deviant stimuli as moderators of full course (30 h) TCT response in treatment-refractory schizophrenia patients randomly assigned to receive either treatment-as-usual (TAU; n = 22) or TAU augmented with TCT (n = 30). Theta evoked power and phase locking at baseline predicted patient improvements in global cognitive function after 30 h of TCT. Decrease in theta activity to deviant stimuli after 1 h of TCT predicted improvements in verbal learning after 30 h. Exploratory analyses using EEG composite scores had high levels of sensitivity and specificity for identifying patients most likely to benefit from TCT. The integrity of baseline neurophysiologic activity associated with EAIP, as well as the sensitivity of the underlying circuity to change, likely reflects an intermediate therapeutic process underlying the effectiveness of TCT that can be used to predict patient response to treatment.

Grant Report on d-Serine Augmentation of Neuroplasticity-Based Auditory Learning in Schizophrenia †

We report on the rationale and design of an ongoing NIMH sponsored R61-R33 project in schizophrenia/schizoaffective disorder. This project studies augmenting the efficacy of auditory neuroplasticity cognitive remediation (AudRem) with d-serine, an N-methyl-d-aspartate-type glutamate receptor (NMDAR) glycine-site agonist. We operationalize improved (smaller) thresholds in pitch (frequency) between successive auditory stimuli after AudRem as improved plasticity, and mismatch negativity (MMN) and auditory θ as measures of functional target engagement of both NMDAR agonism and plasticity. Previous studies showed that AudRem alone produces significant, but small cognitive improvements, while d-serine alone improves symptoms and MMN. However, the strongest results for plasticity outcomes (improved pitch thresholds, auditory MMN and θ) were found when combining d-serine and AudRem. AudRem improvements correlated with reading and other auditory cognitive tasks, suggesting plasticity improvements are predictive of functionally relevant outcomes. While d-serine appears to be efficacious for acute AudRem enhancement, the optimal dose remains an open question, as does the ability of combined d-serine + AudRem to produce sustained improvement. In the ongoing R61, 45 schizophrenia patients will be randomized to receive three placebo-controlled, double-blind d-serine + AudRem sessions across three separate 15 subject dose cohorts (80/100/120 mg/kg). Successful completion of the R61 is defined by ≥moderate effect size changes in target engagement and correlation with function, without safety issues. During the three-year R33, we will assess the sustained effects of d-serine + AudRem. In addition to testing a potentially viable treatment, this project will develop a methodology to assess the efficacy of novel NMDAR modulators, using d-serine as a "gold-standard".

Improving Cognition via Exercise (ICE): Study Protocol for a Multi-Site, Parallel-Group, Single-Blind, Randomized Clinical Trial Examining the Efficacy of Aerobic Exercise to Improve Neurocognition, Daily Functioning, and Biomarkers of Cognitive Change in Individuals with Schizophrenia

Individuals with schizophrenia (SZ) display cognitive deficits that have been identified as major determinants of poor functioning and disability, representing a serious public health concern and an important target for interventions. At present, available treatments offer only minimal to moderate benefits to ameliorate cognitive deficits. Thus, there remains an urgent need to identify novel interventions to improve cognition in people with SZ. Emerging evidence from animal and basic human research suggests aerobic exercise training (AE) has beneficial effects on cognition. Preliminary findings suggest that AE is efficacious in improving cognitive functioning in SZ, however the extant studies have been limited by small samples, a dearth of information on biologically-relevant covariates, and limited information on impact on daily functioning. Additionally, while AE-related cognitive benefits have been linked to Brain-Derived Neurotrophic Factor (BDNF) upregulation, this putative mechanism needs confirmation. The present report describes a study protocol designed to address these limitations-we review and summarize the current literature on treatment of cognitive deficits in SZ, state the rationale for employing AE to target these deficits, and describe the current protocol-a multi-site, single-blind, randomized clinical trial aiming to recruit 200 community-dwelling individuals with SZ. Participants are randomized to one of two 12-week interventions: AE using active-play video games (i.e., Xbox Kinect) and traditional cardiovascular exercise equipment or a stretching-and-toning (ST) control intervention. Participants undergo assessments of aerobic fitness, cognition, and daily functioning, as well as BDNF and other biomarkers of cognitive change, at baseline and after 6-and 12-weeks.

Nicotine effects on cognitive remediation training outcome in people with schizophrenia: A pilot study

Cognitive remediation training can alleviate cognitive impairment associated with schizophrenia, but the impact is limited by small effect sizes. The present study aimed at augmenting training effects by administering nicotine prior to training sessions. Twenty-five people with schizophrenia were enrolled in a 10-week, 5 days/week, computerized cognitive training regimen. Participants were randomized to two treatment groups: nicotine or placebo. Every Monday and Thursday, the nicotine group received a nicotine lozenge before the training, and the placebo group a placebo lozenge. Outcome measurements were conducted on a no-lozenge day in weeks 0, 4, 7, and 10, and at 4-week follow-up. The MATRICS Consensus Cognitive Battery composite score improved over time, but there was no group difference in this effect. A significant group difference emerged over time in the reasoning/problem solving sub-domain: the placebo group improved but not the nicotine group, suggesting that nicotine exposure negatively impacted training benefits on executive control processes. There were no effects on psychiatric symptoms. However, significant improvements were seen across groups on the Quality of Life Scale and the Cognitive Assessment Interview, measuring real-life functional outcome. In conclusion, the present study failed to find evidence that nicotine exposure during cognitive remediation training may potentiate training benefits.

Multi-outcome meta-analysis (MOMA) of cognitive remediation in schizophrenia: Revisiting the relevance of human coaching and elucidating interplay between multiple outcomes

Cognitive remediation (CR) is nowadays mainly administered in a computerized fashion, yet frequently supplemented by human guidance. The effects of CR on cognitive, functional and clinical outcomes are consistently reported, yet the response is heterogeneous. In order to resolve this heterogeneity, we employed a multi-outcome meta-analytic approach, examined effects of CR on each outcome category separately and estimated directed effects between three outcome categories. We extracted treatment effects from 67 studies that trained patients with schizophrenia (total n = 4067) using either 1) computerized CR modality alone or 2) in combination with supplementary human guidance (SHG). All three outcome domains were significantly improved by CR with small to moderate effect sizes when assessing outcomes across all studies. The comparison between CR administered with SHG revealed largest effects on the cognitive subdomains of working and verbal memory. Structural equation modeling in the single-study data suggests that cognitive gains trigger restoration of psychosocial functioning which in turn facilitates improvement in clinical symptoms.

The efficacy of computer-based cognitive training for executive dysfunction in schizophrenia

The purpose of this study was to assess the effect of computer-based cognitive training on executive dysfunction in patients with schizophrenia. Sixty-five patients with schizophrenia were randomly assigned to a training group (n = 33) or a non-training group (n = 32), and compared in terms of executive performance to a healthy control group (n = 33). Executive function was assessed using the Trail Making Test, the Stroop Color and Word Test, and the Wisconsin Card Sorting Test (computer version). Cognitive training was performed using RehaCom software over a course of 16 individual sessions. Primary outcomes were training (performance at three different timepoints) and neuropsychological components (flexibility and cognitive inhibition, high executive processing, and processing speed). In both clinical groups, all aspects of executive function were found to be deficient. In the patient training group, the use of computer-based training alongside pharmacological treatment was more effective in terms of cognitive improvement than pharmacological treatment alone. However, there was no significant effect of cognitive training on processing speed. Cognitive training in schizophrenia patients was effective at improving several aspects of executive function, but did not improve processing speed.

A systematic review of factors that influence the efficacy of cognitive remediation therapy in schizophrenia

OBJECTIVE

Cognitive remediation therapy is a moderately effective intervention for ameliorating cognitive deficits in individuals with schizophrenia-related disorders. With reports of considerable variability in individual response to cognitive remediation therapy, we need to better understand factors that influence cognitive remediation therapy efficacy to realise its potential. A systematic review was conducted to identify and evaluate predictors of cognitive outcome.

METHODS

An electronic database search was conducted identifying peer-reviewed articles examining predictors of cognitive response to cognitive remediation therapy.

RESULTS

A total of 40 articles accounting for 1681 cognitive remediation therapy participants were included; 81 distinct predictors of cognitive response were identified. Data synthesis and discussion focused on 20 predictors examined a minimum three times in different studies. Few of the examined predictors of cognitive outcome following cognitive remediation therapy were significant when examined through systematic review. A strong trend was found for baseline cognition, with reasoning and problem solving and working memory being strongly predictive of within-domain improvement. Training task progress was the most notable cross-domain predictor of cognitive outcome.

CONCLUSION

It remains unclear why a large proportion of participants fail to realise cognitive benefit from cognitive remediation therapy. However, when considering only those variables where a majority of articles reported a statistically significant association with cognitive response to cognitive remediation therapy, three stand out: premorbid IQ, baseline cognition and training task progress. Each of these relates in some way to an individual's capacity or potential for change. There is a need to consolidate investigation of potential predictors of response to cognitive remediation therapy, strengthening the evidence base through replication and collaboration.

Mismatch negativity reveals plasticity in cortical dynamics after 1-hour of auditory training exercises

BACKGROUND

Impaired sensory processing contributes to deficits in cognitive and psychosocial functioning in individuals with schizophrenia (SZ). Mismatch Negativity (MMN), an event-related potential (ERP) index of sensory discrimination associated with cognitive and psychosocial functioning, is a candidate biomarker of auditory discrimination and thus possibly of changes following auditory-based Targeted Cognitive Training (TCT). Here we evaluated the acute effect of TCT on cortical processes supporting auditory discrimination.

METHODS

MMN was assessed in 28 SZ outpatients before and after a single 1-hour (hr) session of "Sound Sweeps," a pitch discrimination task that is a component of the TCT suite of exercises. Independent component (IC) analysis was applied to decompose 64-channel scalp-recorded electroencephalogram (EEG) activity into spatiotemporally stationary sources and their activities. ICs from all patients were pooled to find commonalities in their cortical locations. IC cluster-mean ERPs were evaluated to determine the clusters contributing to the (140-200 ms) MMN difference between responses to deviant and standard tone stimuli respectively.

RESULTS

Two frontal IC clusters centered in orbitofrontal cortex (OFC) and anterior cingulate cortex (ACC) accounted for >77% of MMN variance across all scalp channels. After 1-hr auditory training, significant suppression of ACC cluster contributions was detected, whereas the OFC cluster contribution was unchanged.

CONCLUSIONS

Prior to TCT, the MMN response was dominated by EEG effective sources in or near OFC and ACC. However, after 1-hr of auditory-based TCT, a significant attenuation of ACC was observed, whereas OFC contribution to MMN persisted. The present findings support further trials designed to test whether training-related MMN plasticity in the ACC after 1-hr may predict individual patient response to a full course of TCT.

Evaluation of a plasticity-based cognitive training program in schizophrenia: Results from the eCaesar trial

OBJECTIVE

Cognitive impairment in schizophrenia is a core feature of the disorder. Computerized cognitive training has shown promise in pilot studies. A 26-week randomized blinded placebo-controlled trial was conducted to investigate the effect of a novel computerized cognitive training program on cognitive and functional capacity outcomes.

METHOD

The study followed MATRICS guidelines for the evaluation of interventions designed to improve cognitive function in schizophrenia. Participants (N = 150) were randomized to experimental (computerized cognitive training in a game-like format) or active control (computer games) groups. Training was conducted in-clinic, with an intended training schedule of 5 days per week, 1 h per day, for 26 weeks. Co-primary outcome measures were the MATRICS Consensus Cognitive Battery (MCCB) composite score and the UCSD Performance-Based Skills Assessment (UPSA-2) total score, secondary outcome measures included the Cognitive Assessment Interview (CAI) and the Short-Form-12 Mental Composite Score (SF-12 MCS). Target engagement was assessed with task-learning based assessment.

RESULTS

At baseline, the groups were well matched. No significant effect of the experimental treatment was seen on the primary or secondary outcome measures compared to the active control. Review of the task learning/target engagement data suggested inadequate target engagement.

CONCLUSIONS

Results do not support a cognitive or functional capacity benefit from this implementation of a computerized cognitive training program in people with schizophrenia. In future trials, careful consideration is merited of the assessment of task learning/target engagement, the effects of making the cognitive training game-like on motivation, and the implicit effects of trial requirements on participant selection.

Verbal learning deficits associated with increased anticholinergic burden are attenuated with targeted cognitive training in treatment refractory schizophrenia patients

Targeted cognitive training (TCT) has been reported to improve verbal learning deficits in patients with schizophrenia (SZ). Despite positive findings, it is not clear whether demographic factors and clinical characteristics contribute to the success of TCT on an individual basis. Medication-associated anticholinergic burden has been shown to impact TCT-associated verbal learning gains in SZ outpatients, but the role of anticholinergic medication burden on TCT gains in treatment refractory SZ patients has not been described. In this study, SZ patients mandated to a locked residential rehabilitation center were randomized to treatment as usual (TAU; n=22) or a course of TAU augmented with TCT (n=24). Anticholinergic medication burden was calculated from medication data at baseline and follow-up using the Anticholinergic Cognitive Burden (ACB) Scale. MATRICS Consensus Cognitive Battery Verbal Learning domain scores were used as the primary outcome variable. The TAU and TCT groups were matched in ACB at baseline and follow-up. While baseline ACB was not associated with verbal learning in either group, increases in ACB over the course of the study were significantly associated with deterioration of verbal learning in the TAU group (r=-0.51, p=0.02). This was not seen in subjects randomized to TCT (r=-0.13, p=0.62). Our results suggest that TCT may blunt anticholinergic medication burden associated reduction in verbal learning in severely disabled SZ inpatients.

Motivation and engagement during cognitive training for schizophrenia spectrum disorders

Background

Motivation and engagement are important factors associated with therapeutic outcomes in cognitive training for schizophrenia. The goals of the present report were to examine relations between objective treatment engagement (number of sessions attended, amount of homework completed) and self-reported motivation (intrinsic motivation and perceived competence to complete cognitive training) with neurocognitive and functional outcomes from cognitive training.

Methods

Data from a clinical trial comparing two cognitive training approaches in schizophrenia-spectrum disorders were utilized in the current report (n = 38). Relations were examined between baseline intrinsic motivation, perceived competence, homework completion, and session attendance with improvements in neurocognition, functional competence, and community functioning.

Results

Number of sessions attended (r = 0.38) and time doing homework (r = 0.51) were significantly associated with improvements in neurocognition. Homework completion was associated with change in community functioning at a trend-level (r = 0.30). Older age was associated with greater treatment engagement (β = 0.37) and male biological sex was associated with greater self-reported motivation (β = 0.43). Homework completion significantly mediated the relationship between session attendance and neurocognitive treatment outcomes.

Conclusions

Objective measures of treatment engagement were better predictors of treatment outcomes than subjective measures of motivation. Homework completion was most strongly related to treatment outcomes and mediated the relationship between session attendance and treatment outcomes, suggesting continued engagement with cognitive stimulation may be an especially important component of cognitive remediation programs. Future research should examine methods to improve homework completion and session attendance to maximize therapeutic outcomes.

Training engagement, baseline cognitive functioning, and cognitive gains with computerized cognitive training: A cross-diagnostic study

Computerized cognitive training (CCT) interventions are increasing in their use in outpatient mental health settings. These interventions have demonstrated efficacy for improving functional outcomes when combined with rehabilitation interventions. It has recently been suggested that patients with more cognitive impairment have a greater therapeutic response and that reduced engagement in training can identify cases who manifest low levels of benefit from treatment. Participants were psychiatric rehabilitation clients, with diagnoses of major depression, bipolar disorder and schizophrenia. Newly admitted cases received CCT, delivered via Brain HQ, with cognitive functioning divided into groups on the basis of a BACS t-score of 40 or less vs. more. Training engagement was indexed by the number of training levels achieved per day trained. Forty-nine cases trained on average for 17 days and completed a mean of 150 levels. Overall, patients improved by an average of 4.4 points (0.44 SD) in BACS t-scores (p < .001). Improvements were positively correlated with training engagement (r = 0.30, p < .05), but not with days trained (r = 0.09) or levels earned (r = 0.03) alone. Patients with higher levels of baseline cognitive performance had reduced cognitive gains (p < .003), but did not have less training engagement (p = .97). Diagnoses did not predict cognitive gains (p = .93) or target engagement (p = .74). Poorer performance at baseline and higher levels of training engagement accounted for >10% in independent variance in cognitive gains. The mean level of cognitive improvement far exceeded practice effects. The index of engagement, levels achieved per training day, is easily extracted from the training records of patients, which would allow for early and continuous monitoring of treatment engagement in CCT activities and therapist intervention as needed to improve engagement.

Improving cognitive training for schizophrenia using neuroplasticity enhancers: Lessons from decades of basic and clinical research

Mounting evidence indicates that schizophrenia is a disorder that stems from maladaptive plasticity within neural circuits and produces broad cognitive deficits leading to loss of autonomy. A large number of studies have identified abnormalities spanning many neurotransmitter systems in schizophrenia, and as a result, a variety of drugs have been developed to attempt to treat these abnormalities and enhance cognition. Unfortunately, positive results have been limited so far. This may be in part because the scope of abnormalities in the schizophrenic brain requires a treatment capable of engaging many different neurotransmitter systems. One approach to achieving this kind of treatment has been to use neuroplasticity-based computerized cognitive training programs to stimulate the formation of more adaptive circuits. Although the number of studies implementing this approach has increased exponentially in recent years, effect sizes for cognitive gains have been modest and adherence to treatment remains an important challenge in many studies, as patients are often required to train for 40 h or more. In the present paper, we argue that cognitive training protocols will benefit from the addition of cognitive enhancers to produce more robust and longer lasting targeted neuroplasticity. Indeed, recent data from animal studies have provided support for combining plasticity-enhancing drugs with tailored behavioral training paradigms to restore normal function within dysfunctioning neural circuits. The advantages and challenges of applying this approach to patients with schizophrenia will be discussed.

Association between increased serum d-serine and cognitive gains induced by intensive cognitive training in schizophrenia

Neuroscience-guided cognitive training induces significant improvement in cognition in schizophrenia subjects, but the biological mechanisms associated with these changes are unknown. In animals, intensive cognitive activity induces increased brain levels of the NMDA-receptor co-agonist d-serine, a molecular system that plays a role in learning-induced neuroplasticity and that may be hypoactive in schizophrenia. Here, we investigated whether training-induced gains in cognition were associated with increases in serum d-serine in outpatients with schizophrenia. Ninety patients with schizophrenia and 53 healthy controls were assessed on baseline serum d-serine, l-serine, and glycine. Schizophrenia subjects performed neurocognitive tests and were assigned to 50 h of either cognitive training of auditory processing systems (N = 47) or a computer games control condition (N = 43), followed by reassessment of cognition and serum amino acids. At study entry, the mean serum d-serine level was significantly lower in schizophrenia subjects vs. healthy subjects, while the glycine levels were significantly higher. There were no significant changes in these measures at a group level after the intervention. However, in the active training group, increased d-serine was significantly and positively correlated with improvements in global cognition and in Verbal Learning. No such associations were observed in the computer games control subjects, and no such associations were found for glycine. d-Serine may be involved in the neurophysiologic changes induced by cognitive training in schizophrenia. Pharmacologic strategies that target d-serine co-agonism of NMDA-receptor functioning may provide a mechanism for enhancing the behavioral effects of intensive cognitive training.

A Randomized Controlled Trial of Executive Functioning Training Compared With Perceptual Training for Schizophrenia Spectrum Disorders: Effects on Neurophysiology, Neurocognition, and Functioning

OBJECTIVE

Cognitive remediation is an efficacious treatment for schizophrenia. However, different theoretical approaches have developed without any studies to directly compare them. This is the first study to compare the two dominant approaches to cognitive remediation (training of executive skills and training of perceptual skills) and employed the broadest assessment battery in the literature to date.

METHODS

Outpatients with schizophrenia spectrum disorders were randomly assigned to receive either executive training or perceptual training. Electrophysiological activity, neurocognition, functional competence, case manager-rated community functioning, clinical symptoms, and self-report measures were assessed at baseline, immediately after treatment, and at a 12-week posttreatment follow-up assessment.

RESULTS

Perceptual training improved the EEG mismatch negativity significantly more than executive training immediately after treatment, although the effect did not persist at the 12-week follow-up. At the follow-up, executive training improved theta power during an n-back task, neurocognition, functional competence, and case manager-rated community functioning to a greater extent than perceptual training. These effects were not observed immediately after treatment.

CONCLUSIONS

Both perceptual training and executive training improved neurophysiological mechanisms specific to their domains of intervention, although only executive training resulted in improvement in neurocognition and functioning. Improvements in favor of executive training did not appear immediately after treatment but emerged 12 weeks after the end of active treatment. Thus, short-term intervention targeting higher-order cognitive functions may prime further cognitive and functional improvement.