The effect of coping strategies on health-related quality of life in acromegaly patients

PURPOSE

Patients with acromegaly oftentimes exhibit a reduced physical and psychological health-related quality of life (HRQoL). Maladaptive coping styles are associated with poor HRQoL in a number of diseases and patients with pituitary adenomas in general exhibit less effective coping styles than healthy controls. This study aimed to assess coping strategies in acromegaly patients in order to explore leverage points for the improvement of HRQoL.

METHODS

In this cross-sectional study, we administered self-report surveys for coping strategies and HRQoL (Short Form SF-36, Freiburg questionnaire on coping with illness, FKV-LIS) in patients with acromegaly. These were set into relation with a variety of health variables.

RESULTS

About half of the 106 patients (44.3% female) with a mean age of 56.4 ± 1.3 years showed impaired physical and psychological HRQoL on average 11.2 years after the initial diagnosis. Body mass index, age at survey date and concomitant radiotherapy explained 27.8% of the variance of physical HRQoL, while depressive coping added an additional 9.2%. Depressive coping style and trivialization and wishful thinking were pivotal predictors of an impaired psychological HRQoL with a total explained variance of 51.6%, whereas patient health variables did not affect psychological HRQoL.

CONCLUSION

Our results show that maladaptive coping styles have a substantial negative impact on psychological HRQoL in patients with acromegaly, whereas physical HRQoL is influenced to a lesser extent. Specialized training programs aimed at improving coping strategies could reduce long-term disease burden and increase HRQoL in the affected patients.

The influence of radiological tumor growth pattern on sino‑nasal health in pituitary adenomas

Pituitary adenomas are one of the most common mass lesions of the brain and are associated with a reduced quality of life. While transnasal and transsphenoidal endoscopic approaches are considered to deliver similar recovery rates for sino-nasal health (SNH), the impact of radiological tumor growth patterns on SNH has not been evaluated. In the present study, the influence of radiological tumor growth on SNH was examined before and after endoscopic transsphenoidal tumor resection. Patient data were prospectively collected between August 1, 2016 and August 31, 2022. The Knosp and Hardy classifications were used to dichotomize pituitary adenoma lesions into low- and high-graded lesions. SNH was assessed shortly before surgery and at follow-up examinations 3-6 months after operation using the Sino-Nasal Outcome Test for Neurosurgery (SNOT-NC) questionnaire. Fully completed SNOT-NC questionnaires were collected before and after surgery from a total of 101 patients. Independent t-tests showed significantly higher rates of deterioration after surgery in patients with Knosp low-graded lesions compared with those with high-graded tumors for the SNOT-NC total score P=0.048, nasal discomfort P=0.034, sleep problems P=0.024 and visual impairment P=0.042. Pre- and post-operative comparisons for the Knosp low-graded tumor cohort showed an increase of nasal discomfort (P=0.004), while the Knosp high-graded tumor cohort reported decreased visual impairment (P=0.016) after surgery. Assessing the Hardy classification, increased nasal discomfort was reported in patients with high-graded infrasellar tumors after surgery (P=0.046). Growth characteristics of pituitary adenomas based on Knosp and Hardy classifications may influence SNH. Patients with less invasive lesions were revealed to be more prone to experiencing a decrease in SNH, which went beyond the assumed deterioration of 1-3 months. These findings indicate the importance of detailed information regarding SNH as part of every pre-operative patient briefing.

Variables associated with oral health-related self-efficacy - results of a cross-sectional study

BACKGROUND

Oral health-related self-efficacy (OH-SE) is pivotal for oral health and is associated with other oral-health related variables, such as dental fear and anxiety (DF/A) and dental hygiene behaviors (DHB). This study attempts to analyze associations between OH-SE and oral healthrelated variables in a German population to extend previous research by analyzing whether OH-SE can be predicted by these variables, as this might contribute to the development of treatment interventions.

METHODS

OH-SE, DF/A, oral health-related quality of life (OHRQoL), self-perceived dental condition, satisfaction with general health, DHB, and socioeconomic status were assessed as a part of the Saxon Longitudinal Study in an adult sample (n = 309, 56.3% female, all Saxon secondary school 8th graders in 1987). The associations of OH-SE with these variables were examined by means of correlation, multiple linear regression analyses, and group comparisons. Significance (p), standardized regression coefficients (β), and effect size (Cohen's d) were calculated.

RESULTS

The correlation analyses revealed increased OH-SE to be accompanied by low levels of DF/A, high levels of OHRQoL, high levels of self-perceived dental condition, increased satisfaction with general health and socioeconomic status (all r ≥ 0.142; all p ≤ 0.013). In the regression analysis, OH-SE was mainly predicted by self-perceived dental condition and satisfaction with general health (R2 = 0.157) as well as by daily frequency of toothbrushing, OHRQoL, and socioeconomic status on a trend-level basis. In the group comparisons OH-SE was lower in participants with moderate for manifest DF/A and higher in individuals with higher OHRQoL, better self-perceived dental condition, increased satisfaction with general health, increased daily frequency of toothbrushing, more dental appointments, and above-average socioeconomic status (trend level; all t ≥ 1.57; p ≤ 0.059).

CONCLUSIONS

In this cross-sectional study, high levels of OH-SE were mainly predicted by general health as well as self-perceived dental condition. It was also associated with decreased DF/A, increased DHB, higher OHRQoL, and higher socioeconomic status. Future research should analyze these associations in longitudinal designs to address whether interventions focusing on adherence to good DHB improve (dental) health and thus OH-SE. This might be a promising approach, particularly in relation to the treatment of DF/A.

Pituitary enlargement in patients with cerebrospinal fluid drainage due to ventricular shunt insertion: know the condition and do not mistake for adenoma

OBJECTIVE

Childhood hydrocephalus patients treated by ventriculo-peritoneal (v.-p.) shunting are sometimes referred years after this therapy for evaluation of suspicious pituitary enlargement. Since pituitary size has been shown to depend on cerebrospinal fluid (CSF) pressure, we assume this phenomenon to be caused by shunt overdrainage. Therefore, we studied pituitary size and morphology in shunted hydrocephalus patients with radiological signs of high CSF drainage.

PATIENTS AND METHODS

Retrospective study of pituitary size and morphology in 15 shunted patients with non-tumoral hydrocephalus and 7 shunted hydrocephalus patients due to childhood brain tumor compared to a population mean. In five brain tumor patients also pre- and postsurgical comparisons were performed.

RESULTS

Pituitary mid-sagittal size and pituitary volume were significantly higher in both hydrocephalus groups, compared to the population mean (midsagittal size t = 5.91; p < 0.001; pituitary volume, t = 3.03; p = 0.006). In patients available for pre- and postoperative comparison, there was also a significant increase in pituitary size and volume postoperatively (mean preoperative midsagittal height 2.54 ± 1.0 mm vs. 6.6 ± 0.7 mm post-surgery; mean pre-operative pituitary volume 120.5 ± 69.2 mm³ vs. 368.9 ± 57.9 mm³ post-surgery).

CONCLUSION

Our results confirmed a significant increase in pituitary size and volume, mimicking pituitary pathology, after v.-p. shunt insertion. This phenomenon can be explained by the Monro-Kellie doctrine, stating that intracranial depletion of CSF-as caused by v.p. shunting-leads to compensatory intracranial hyperemia, especially in the venous system, with the consequence of engorged venous sinuses, most likely responsible for enlargement of the pituitary gland.

Pre-Surgery Patient Health Contributes to Aggravated Sino-Nasal Outcome and Quality of Life after Pituitary Adenomectomy

Objectives: The transphenoidal bi-nostril endoscopic resection of pituitary adenomas is regarded as a minimally invasive treatment nowadays. However, sino-nasal outcome and health-related quality of life (HRQoL) might still be impaired after the adenomectomy, depending on patients' prior medical history and health status. A systematic postoperative comparison is required to assess differences in perceived sino-nasal outcome and HRQoL. Methods: In this single-center observational study, we collected data from 81 patients, operated between August 2016 and August 2021, at a 3-6-month follow-up after adenomectomy. We employed the sino-nasal outcome test for neurosurgery (SNOT-NC) and the HRQoL inventory Short Form (SF)-36 to compare sino-nasal and HRQoL outcome in patients with or without allergies, previous nose surgeries, presence of pain, snoring, sleep apnea, usage of continuous positive airway pressure (cpap), and nose drop usage. Results: At the 3-6-month follow-up, patients with previous nasal surgery showed overall reduced subjective sino-nasal health, increased nasal and ear/head discomfort, increased visual impairment, and decreased psychological HRQoL (all p ≤ 0.026) after pituitary adenomectomy. Patients with pain before surgery showed a trend-level aggravated physical HRQoL (p = 0.084). Conclusion: Our data show that patients with previous nasal surgery have an increased risk of an aggravated sino-nasal and HRQoL outcome after pituitary adenomectomy. These patients should be thoroughly informed about potential consequences to induce realistic patient expectations. Moreover, the study shows that patients with moderately severe allergies, snoring, and sleep apnea (± cpap) usually do not have to expect a worsened sino-nasal health and HRQoL outcome.

Quality of life and mood assessment in conservatively treated cavernous malformation-related epilepsy

BACKGROUND

To estimate the quality of life, anxiety, depression, and illness perception in patients with medically treated cerebral cavernous malformation (CCM) and associated epilepsy.

METHODS

Nonsurgically treated patients with CCM-related epilepsy (CRE) were included. Demographic, radiographic, and clinical features were assessed. All participants received established questionnaires (short-form 36 health survey, SF-36; hospital anxiety and depression score, HADS-A/D; visual analogue scale score, VAS) assessing the functional and psychosocial burden of disease. To some extent, calculated values were compared with reference values from population-based studies. Test results were related to seizure control.

RESULTS

A total of 37 patients were included. Mean age was 45.8 ± 14.4 years, and 54.1% were female. Diagnosis of CRE was significantly associated with attenuated quality of life and increased level of anxiety, affecting physical and psychosocial dimensions. The assessment of illness perception identified considerable burden. HADS was significantly associated with VAS and SF-36 component scores. Efficacy of antiepileptic medication had no restoring impact on quality of life, anxiety, depression, or illness perception.

CONCLUSIONS

CRE negatively influences quality of life and mood, independent of seizure control due to antiepileptic medication. Screening for functional and psychosocial deficits in clinical practice might be useful for assessing individual burden and allocating surgical or drug treatment.

Intact Context-Dependent Modulation of Conflict Monitoring in Childhood ADHD

Objective: Conflict monitoring is well known to be modulated by context. This is known as the Gratton effect, meaning that the degree of interference is smaller when a stimulus-response conflict had been encountered previously. It is unclear to what extent these processes are changed in ADHD. Method: Children with ADHD (combined subtype) and healthy controls performed a modified version of the sequence flanker task. Results: Patients with ADHD made significantly more errors than healthy controls, indicating general performance deficits. However, there were no differences regarding reaction times, indicating an intact Gratton effect in ADHD. These results were supported by Bayesian statistics. Conclusion: The results suggest that the ability to take contextual information into account during conflict monitoring is preserved in patients with ADHD despite this disorder being associated with changes in executive control functions overall. These findings are discussed in light of different theoretical accounts on contextual modulations of conflict monitoring.

How high-dose alcohol intoxication affects the interplay of automatic and controlled processes

Binge drinking is an increasingly prevalent pattern of alcohol consumption that impairs top-down cognitive control to a much stronger degree than automatic response generation. Even though an imbalance of those two antagonistic processes fosters the development and maintenance of alcohol use disorders (AUDs), it has never been directly investigated how binge drinking affects the interaction of those two processes. We therefore assessed a sample of n = 35 healthy young men who were asked to perform a newly developed Simon Nogo paradigm once sober and once intoxicated (~1.2‰) in a balanced within-subject design. Additionally, an EEG was recorded to dissociate controlled and automatic cognitive subprocesses. The results demonstrate that alcohol seems to reduce top-down cognitive control. This control impairment was associated with changes in S-R mapping (reflected by a reduced parietal P3 amplitude), top-down response selection (reflected by modulations of lateralized readiness potentials), and (the evaluation of) response inhibition (reflected by modulations of the Nogo P3). In sharp contrast to this, automatic processing does not seem to be equally altered, as we found neither increases nor decreases in this domain. Most importantly, we also found that the interaction between control and automatisms might be less impaired by alcohol than control alone, which may help to overcome alcohol-induced response inhibition deficits. These "carryover" effects of control from one domain to the other could potentially prove beneficial in AUDs.

How non-veridical perception drives actions in healthy humans: evidence from synaesthesia

We continually perform actions that are driven by our perception and it is a commonly held view that only objectively perceived changes within the 'real' world affect behaviour. Exceptions are generally only made for mental health disorders associated with delusions and hallucinations where behaviour may be triggered by the experience of objectively non-existent percepts. Here, we demonstrate, using synaesthesia as a model condition (in N = 19 grapheme-colour synaesthetes), how objectively non-existent (i.e. non-veridical) but still non-pathological perceptions affect actions in healthy humans. Using electroencephalography, we determine whether early-stage perceptual processes (reflected by P1 and N1 event-related potential (ERP) components), or late-stage-integration processes (reflected by N2 component), underlie the effects of non-veridical perceptions on action control. ERP analysis suggests that even though the examined peculiarities and experimental variations are perceptual in nature, it is not early-stage perceptual processes, but rather higher-order executive control processes linking perceptions to the appropriate motor response underlying this effect. Source localization analysis implicates activation within medial frontal cortices in the effect of how irrelevant non-veridical perceptions modulate behaviour. Our results challenge common conceptions about the determinants of human behaviour but can be explained by well-established theoretical frameworks detailing the link between perception and action. This article is part of a discussion meeting issue 'Bridging senses: novel insights from synaesthesia'.

How perceptual ambiguity affects response inhibition processes

The ability to inhibit responses is a central requirement for goal-directed behavior but has been dominated by a top-down or cognitive control view. Only recently, the role of bottom-up perceptual factors were focused in research. However, studies usually use clearly distinguishable stimulus categories to trigger response execution or inhibition. In the current study, we present a novel Gabor patch Go/No-go task to induce perceptual ambiguity during response inhibition. To examine the neurophysiological processes in detail, we use EEG recordings and combined temporal EEG signal decomposition methods with source localization analyses. We show that perceptual similarity between Go and No-go trials compromises response inhibition performance. Interestingly, the EEG data show that this is due to a modulation of stimulus-response transition or decision processes, and not purely stimulus-related processes. This was possible by applying a temporal EEG decomposition method. We provide evidence that a prefrontal P2 (pP2) likely reflects decision processes on action execution using stimulus information. These processes were associated with superior and middle prefrontal regions (BA8). When these processes fail, occasions to execute a response become misinterpreted as occasions to inhibit a response. Successful and unsuccessful decisions to inhibit a response under high perceptual ambiguity seem to further depend on how well "what-decisions," supported by neural mechanisms in BA19, can be processed. However, these what-decisions seem to be closely linked to the specification of the required action. Stimulus processing is closely linked to response programming so that response control is already informed when uncertainty with regard to stimulus identity is detected.NEW & NOTEWORTHY This study introduces a novel Go/No-go paradigm and shows what neurophysiological subprocesses and functional neuroanatomical are involved during inhibitory control when ambiguous stimulus input is provided. The results show that bottom-up perceptual processes are important to consider during top-down controlled response inhibition. Stimulus processing is closely linked to response programming so that response control is already informed when uncertainty with regard to stimulus identity is detected.

Stimulus Feature Conflicts Enhance Motor Inhibitory Control Processes in the Lateral Prefrontal Cortex

The ability to inhibit prepotent responses is a central facet of cognitive control. However, the role of perceptual factors in response inhibition processes is still poorly understood and an underrepresented field of research. In the current study, we focus on the role of conflicts between perceptual stimulus features (so-called S-S conflicts) for response inhibition. We introduce a novel semantic Stroop Condition task and analyze EEG data using source localization and temporal EEG signal decomposition methods to delineate the neural mechanisms how semantic S-S conflicts modulate response inhibition. We show that semantic conflicts enhance response inhibition performance by modulating neural processes relating to conflict resolution mechanisms in the middle and inferior frontal cortex, as well as the ACC. Opposed to that, Stroop-like (S-S) conflicts compromise response execution by affecting decision processes in inferior parietal cortices. The data suggest that when action control processes and their neurophysiological correlates depend on regions specialized in the processing of semantic conflicts, there is an improvement in response inhibition. The results show that Stroop-like semantic conflicts have opposite effects depending on whether a response has to be executed or inhibited. These opposing effects are then also associated with different functional-neuroanatomical structures. The results of the study show mechanisms by which stimulus-related processes influence mechanisms of response control.

Detrimental effects of a high-dose alcohol intoxication on sequential cognitive flexibility are attenuated by practice

It is well-known that alcohol impairs behavioral control and motor response inhibition, but it has remained rather unclear whether it also impairs cognitive inhibition. As automatized behavior is less vulnerable towards the detrimental effects of alcohol than cognitive control processes, potential cognitive inhibition deficits might however improve with training. We investigated the effect of an acute, binge-like alcohol intoxication in a balanced within-subjects design, asking n=32 healthy young males to perform a backward inhibition paradigm once sober and once while intoxicated (~1.1 ‰). To identify the underlying neurophysiological mechanisms, we analyzed stimulus- and response selection-related processes in neurophysiological data after Residue Iteration Decomposition (RIDE). Alcohol generally impaired behavioral task performance (accuracy and response times) during task switching. This was associated with impaired attentional processing of the task-relevant cue (reflected by reduced P1 and N1 amplitudes), which likely resulted in a larger need for reactive control at the later stage of response selection and control (reflected by increased fronto-central theta power). Without prior practice (~30 minutes), the intoxicated participants further struggled to overcome the cognitive inhibition of a previously relevant task set (reflected by a larger backward inhibition effect). This was linked to reduced posterior theta power, which reflects alcohol-induced impairments in working memory capacity and task set-relevant memory retrieval. As individuals with ~30 min task practice did not show the same alcohol-related deficit, it may be deduced that (partial) task set automatization via stimulus-response associations may help to reduce the detrimental effects of alcohol on cognitive inhibition during task switching.

Working memory load affects repetitive behaviour but not cognitive flexibility in adolescent autism spectrum disorder

OBJECTIVES

Autism spectrum disorder (ASD) is associated with repetitive and stereotyped behaviour, suggesting that cognitive flexibility may be deficient in ASD. A central, yet not examined aspect to understand possible deficits in flexible behaviour in ASD relates (i) to the role of working memory and (ii) to neurophysiological mechanisms underlying behavioural modulations.

METHODS

We analysed behavioural and neurophysiological (EEG) correlates of cognitive flexibility using a task-switching paradigm with and without working memory load in adolescents with ASD and typically developing controls (TD).

RESULTS

Adolescents with ASD versus TD show similar performance in task switching with no memory load, indicating that 'pure' cognitive flexibility is not in deficit in adolescent ASD. However performance during task repetition decreases with increasing memory load. Neurophysiological data reflect the pattern of behavioural effects, showing modulations in P2 and P3 event-related potentials.

CONCLUSIONS

Working memory demands affect repetitive behaviour while processes of cognitive flexibility are unaffected. Effects emerge due to deficits in preparatory attentional processes and deficits in task rule activation, organisation and implementation of task sets when repetitive behaviour is concerned. It may be speculated that the habitual response mode in ASD (i.e. repetitive behaviour) is particularly vulnerable to additional demands on executive control processes.

Effects of multisensory stimuli on inhibitory control in adolescent ADHD: It is the content of information that matters

Even though deficits in inhibitory control and conflict monitoring are well-known in ADHD, factors that further modulate these functions remain to be elucidated. One factor that may be of considerable importance is how inhibitory control is modulated by multisensory information processing. We examined the influence of concurrent auditory conflicting or redundant information on visually triggered response inhibition processes in adolescent ADHD patients and healthy controls. We combined high-density event-related potential (ERP) recordings with source localization to delineate the functional neuroanatomical basis of the involved neurophysiological processes. In comparison to controls, response inhibition (RI) processes in ADHD were compromised in conflicting conditions, but showed no differences to controls when redundant or no concurrent auditory information was presented. These effects were reflected by modulations at the response selection stage (P3 ERP) in the medial frontal gyrus (BA32), but not at the attentional selection (P1, N1 ERPs) or resource allocation level (P2 ERP). Conflicting information during RI exerts its influences in adolescent ADHD via response selection mechanisms, but not via attentional selection. It is not the mere presence of concurrent information, but the presence of conflicting information during RI that may destabilize goal shielding processes in medial frontal cortical regions, by means of increasing the automaticity of response tendencies. The occurring RI deficits might relate to the increased impulsivity in adolescent ADHD and a corresponding vulnerability to react to an increased automaticity of pre-potent response tendencies. ADHD patients show a bias to a specific content of information which can modulate inhibitory control.

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Response inhibition (RI) performance in ADHD is modulated by multisensory information.

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Only incongruent/conflicting concurrent information modulates RI performance.

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RI deficits occur if this conflicting information braces the automaticity of response tendencies.

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These deficits relate to a predisposition of ADHD to engage in impulsive behavior.

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This may be due to deficient goal-shielding processes located in the MFG.

Response selection codes in neurophysiological data predict conjoint effects of controlled and automatic processes during response inhibition

The inhibition of prepotent responses is a requirement for goal-directed behavior and several factors determine corresponding successful response inhibition processes. One factor relates to the degree of automaticity of pre-potent response tendencies and another factor relates to the degree of cognitive control that is exerted during response inhibition. However, both factors can conjointly modulate inhibitory control. Cognitive theoretical concepts suggest that codings of stimulus-response translations may underlie such conjoint effects. Yet, it is unclear in how far such specific codes, as assumed in cognitive psychological concepts, are evident in neurophysiological processes and whether there are specific functional neuroanatomical structures associated with the processing of such codes. Applying a temporal decomposition method of EEG data in combination with source localization methods we show that there are different, intermingled codes (i.e., "stimulus codes" and "response selection codes") at the neurophysiological level during conjoint effects of "automatic" and "controlled" processes in response inhibition. Importantly, only "response selection codes" predict behavioral performance, and are subject to conjoint modulations by "automatic" and "controlled" processes. These modulations are associated with inferior and superior parietal areas (BA40/BA7), possibly reflecting an updating of internal representations when information is complex and probably difficult to categorize, but essential for behavioral control. Codes proposed by cognitive, psychological concepts seem to have a neurophysiological analogue that fits into current views on functions of inferior and superior parietal regions.

Neuronal Intra-Individual Variability Masks Response Selection Differences between ADHD Subtypes-A Need to Change Perspectives

Due to the high intra-individual variability in attention deficit/hyperactivity disorder (ADHD), there may be considerable bias in knowledge about altered neurophysiological processes underlying executive dysfunctions in patients with different ADHD subtypes. When aiming to establish dimensional cognitive-neurophysiological constructs representing symptoms of ADHD as suggested by the initiative for Research Domain Criteria, it is crucial to consider such processes independent of variability. We examined patients with the predominantly inattentive subtype (attention deficit disorder, ADD) and the combined subtype of ADHD (ADHD-C) in a flanker task measuring conflict control. Groups were matched for task performance. Besides using classic event-related potential (ERP) techniques and source localization, neurophysiological data was also analyzed using residue iteration decomposition (RIDE) to statistically account for intra-individual variability and S-LORETA to estimate the sources of the activations. The analysis of classic ERPs related to conflict monitoring revealed no differences between patients with ADD and ADHD-C. When individual variability was accounted for, clear differences became apparent in the RIDE C-cluster (analog to the P3 ERP-component). While patients with ADD distinguished between compatible and incompatible flanker trials early on, patients with ADHD-C seemed to employ more cognitive resources overall. These differences are reflected in inferior parietal areas. The study demonstrates differences in neuronal mechanisms related to response selection processes between ADD and ADHD-C which, according to source localization, arise from the inferior parietal cortex. Importantly, these differences could only be detected when accounting for intra-individual variability. The results imply that it is very likely that differences in neurophysiological processes between ADHD subtypes are underestimated and have not been recognized because intra-individual variability in neurophysiological data has not sufficiently been taken into account.

Effects of multisensory integration processes on response inhibition in adolescent autism spectrum disorder

BACKGROUND

In everyday life it is often required to integrate multisensory input to successfully conduct response inhibition (RI) and thus major executive control processes. Both RI and multisensory processes have been suggested to be altered in autism spectrum disorder (ASD). It is, however, unclear which neurophysiological processes relate to changes in RI in ASD and in how far these processes are affected by possible multisensory integration deficits in ASD.

METHOD

Combining high-density EEG recordings with source localization analyses, we examined a group of adolescent ASD patients (n = 20) and healthy controls (n = 20) using a novel RI task.

RESULTS

Compared to controls, RI processes are generally compromised in adolescent ASD. This aggravation of RI processes is modulated by the content of multisensory information. The neurophysiological data suggest that deficits in ASD emerge in attentional selection and resource allocation processes related to occipito-parietal and middle frontal regions. Most importantly, conflict monitoring subprocesses during RI were specifically modulated by content of multisensory information in the superior frontal gyrus.

CONCLUSIONS

RI processes are overstrained in adolescent ASD, especially when conflicting multisensory information has to be integrated to perform RI. It seems that the content of multisensory input is important to consider in ASD and its effects on cognitive control processes.

The norepinephrine system affects specific neurophysiological subprocesses in the modulation of inhibitory control by working memory demands

Inhibitory control processes are known to be modulated by working memory demands. However, the neurobiological mechanisms behind these modulations are inconclusive. One important system to consider in this regard is the locus coeruleus (LC) norepinephrine (NE) system. In the current study the role of the LC-NE system by means of pupil diameter recordings that are integrated with neurophysiological (EEG) and source localization data were examined. A combined mental-rotation Go/Nogo task was used. The results show that increases in working memory load complicate response inhibition processes. On a neurophysiological level these effects were reflected by specific modulations in event-related potentials (ERPs) reflecting motor inhibition processes (i.e., Nogo-P3). Attentional selection processes (reflected by the P1 and N1) as well as pre-motor inhibition or conflict monitoring processes (reflected by the Nogo-N2) were not affected. Activity of the LC-NE systems, as indexed by the pupil diameter data, predicted neurophysiological processes selectively in the Nogo-P3 time range. Source localization analyses suggest that this modulation occurs in the right middle and inferior frontal gyrus. The study provides evidence that the LC-NE system is an important neurobiological system modulating the effects of working memory load on response inhibition processes. More specifically, it modulates a subset of dissociable cognitive processes that are related to prefrontal cortical regions. Hum Brain Mapp 38:68-81, 2017. © 2016 Wiley Periodicals, Inc.

Perceptual conflict during sensorimotor integration processes - a neurophysiological study in response inhibition

A multitude of sensory inputs needs to be processed during sensorimotor integration. A crucial factor for detecting relevant information is its complexity, since information content can be conflicting at a perceptual level. This may be central to executive control processes, such as response inhibition. This EEG study aims to investigate the system neurophysiological mechanisms behind effects of perceptual conflict on response inhibition. We systematically modulated perceptual conflict by integrating a Global-local task with a Go/Nogo paradigm. The results show that conflicting perceptual information, in comparison to non-conflicting perceptual information, impairs response inhibition performance. This effect was evident regardless of whether the relevant information for response inhibition is displayed on the global, or local perceptual level. The neurophysiological data suggests that early perceptual/ attentional processing stages do not underlie these modulations. Rather, processes at the response selection level (P3), play a role in changed response inhibition performance. This conflict-related impairment of inhibitory processes is associated with activation differences in (inferior) parietal areas (BA7 and BA40) and not as commonly found in the medial prefrontal areas. This suggests that various functional neuroanatomical structures may mediate response inhibition and that the functional neuroanatomical structures involved depend on the complexity of sensory integration processes.

The neural architecture of age-related dual-task interferences

In daily life elderly adults exhibit deficits when dual-tasking is involved. So far these deficits have been verified on a behavioral level in dual-tasking. Yet, the neuronal architecture of these deficits in aging still remains to be explored especially when late-middle aged individuals around 60 years of age are concerned. Neuroimaging studies in young participants concerning dual-tasking were, among others, related to activity in middle frontal (MFG) and superior frontal gyrus (SFG) and the anterior insula (AI). According to the frontal lobe hypothesis of aging, alterations in these frontal regions (i.e., SFG and MFG) might be responsible for cognitive deficits. We measured brain activity using fMRI, while examining age-dependent variations in dual-tasking by utilizing the PRP (psychological refractory period) test. Behavioral data showed an increasing PRP effect in late-middle aged adults. The results suggest the age-related deteriorated performance in dual-tasking, especially in conditions of risen complexity. These effects are related to changes in networks involving the AI, the SFG and the MFG. The results suggest that different cognitive subprocesses are affected that mediate the observed dual-tasking problems in late-middle aged individuals.