Cognitive functioning in compulsive hoarding

Learning and memory processes in behavioural addiction: A systematic review

Similar to addictive substances, addictive behaviours such as gambling and gaming are associated with maladaptive modulation of key brain areas and functional networks implicated in learning and memory. Therefore, this review sought to understand how different learning and memory processes relate to behavioural addictions and to unravel their underlying neural mechanisms. Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we systematically searched four databases - PsycINFO, PubMed, Scopus, and Web of Science using the agreed-upon search string. Findings suggest altered executive function-dependent learning processes and enhanced habit learning in behavioural addiction. Whereas the relationship between working memory and behavioural addiction is influenced by addiction type, working memory aspect, and task nature. Additionally, long-term memory is incoherent in individuals with addictive behaviours. Consistently, neurophysiological evidence indicates alterations in brain areas and networks implicated in learning and memory processes in behavioural addictions. Overall, the present review argues that, like substance use disorders, alteration in learning and memory processes may underlie the development and maintenance of behavioural addictions.

The relationship between cognitive phenotypes of compulsivity and impulsivity and clinical variables in obsessive-compulsive disorder: A systematic review and Meta-analysis

BACKGROUND

This systematic review and meta-analysis explored the relationship between cognitive phenotypes of compulsivity and impulsivity and clinical variables in obsessive-compulsive disorder (OCD).

METHODS

We searched Pubmed, Scopus, Cochrane Library and PsychINFO databases until February 2023 for studies comparing patients with OCD and healthy controls on cognitive tests of compulsivity and impulsivity. The study followed PRISMA guidelines and was pre-registered on PROSPERO (CRD42021299017).

RESULTS

Meta-analyses of 112 studies involving 8313 participants (4289 patients with OCD and 4024 healthy controls) identified significant impairments in compulsivity (g = -0.58, [95%CI -0.68, -0.47]; k = 76) and impulsivity (g = -0.48, [95%CI -0.57, -0.38]; k = 63); no significant difference between impairments. Medication use and comorbid psychiatric disorders were not significantly related to impairments. No associations were revealed with OCD severity, depression/anxiety, or illness duration.

CONCLUSION

Cognitive phenotypes of compulsivity and impulsivity in patients with OCD appear to be orthogonal to clinical variables, including severity of OCD symptomatology. Their clinical impact is poorly understood and may require different clinical assessment tools and interventions.

Increased error rate and delayed response to negative emotional stimuli in antisaccade task in obsessive-compulsive disorder

Ample evidence links impaired inhibitory control, attentional distortions, emotional dysregulation, and obsessive-compulsive disorder (OCD). However, it remains unclear what underlies the deficit that triggers the OCD cycle. The present study used an antisaccade paradigm with emotional valences to compare eye movement patterns reflecting inhibitory control and attention switching in OCD and healthy control groups. Thirty-two patients with OCD and thirty healthy controls performed the antisaccade task with neutral, positive, and negative visual images served as fixation stimuli. Presentation of the fixation stimulus overlapped with target stimuli appearance for 200 ms. The OCD group showed more errors to negative stimuli than the control group and they also performed antisaccades more slowly to negative and neutral stimuli than positive ones. Other patterns, including mean gaze velocity of correct antisaccades did not differ between groups. The mean gaze velocity of correct antisaccades was higher for negative and positive stimuli than for neutral stimuli in both groups. The peak velocity parameter did not show any differences either between groups or between valences. The findings support a hypothesis that an attentional bias toward negative stimuli interferes with inhibitory control in OCD.

Psychological mechanism of acceptance and commitment therapy and rational emotive behavior therapy for treating hoarding: Evidence from randomized controlled trials

Hoarding is a common problem behavior worldwide and is detrimental to the physical and mental health of individuals and groups. Currently, effective interventions for hoarding are cognitive-behavioral therapies, but their post-intervention efficacy is questionable, and the available research does not examine the mediating variables of the effects of interventions on clinical outcomes. Moreover, current research on hoarding has focused on Western countries. Therefore, there is a need to investigate the efficacy of other forms of cognitive behavioral therapy on hoarding as well as other psychological outcomes related to hoarding and mediating variables that contribute to its effectiveness in different cultural contexts. One hundred thirty-nine college students with higher hoarding behaviors were randomly divided into three groups: 45 in the Acceptance and Commitment Therapy (ACT) group, 47 in the Rational Emotive Behavior Therapy (REBT) group, and 47 in the control group. They completed the Saving Inventory-Revised (SI-R), Obsessive-Compulsive Symptom Scale (OCSS), Difficulties in Emotion Regulation Scale (DERS), Experiences in Close Relationships Inventory-Attachment Anxiety Subscale (ECR), Depression Anxiety Stress Scales (DASS-21), Acceptance and Action Questionnaire II (AAQ-II), and Cognitive Fusion Questionnaire (CFQ) before and immediately after the intervention. The results showed that ACT and REBT improved individuals' psychological flexibility, cognitive fusion, acquisition-difficulty discarding, clutter, negative affect (anxiety, depression, stress), attachment anxiety, obsessive-compulsive disorder, and difficulty in emotion regulation compared to the control group. In addition, ACT was more effective than REBT in improving psychological flexibility and reducing hoarding, cognitive fusion, depression, stress, and obsessive-compulsive disorder; there were no significant differences between the two in anxiety and emotion regulation difficulties. Furthermore, psychological flexibility is a mediator of the effect of ACT and REBT on some behavioral and psychological outcomes (hoarding, negative affect, attachment anxiety). Limitations were discussed.

The Complexity of the Human-Animal Bond: Empathy, Attachment and Anthropomorphism in Human-Animal Relationships and Animal Hoarding

The human-animal relationship is ancient, complex and multifaceted. It may have either positive effects on humans and animals or poor or even negative and detrimental effects on animals or both humans and animals. A large body of literature has investigated the beneficial effects of this relationship in which both human and animals appear to gain physical and psychological benefits from living together in a reciprocated interaction. However, analyzing the literature with a different perspective it clearly emerges that not rarely are human-animal relationships characterized by different forms and levels of discomfort and suffering for animals and, in some cases, also for people. The negative physical and psychological consequences on animals' well-being may be very nuanced and concealed, but there are situations in which the negative consequences are clear and striking, as in the case of animal violence, abuse or neglect. Empathy, attachment and anthropomorphism are human psychological mechanisms that are considered relevant for positive and healthy relationships with animals, but when dysfunctional or pathological determine physical or psychological suffering, or both, in animals as occurs in animal hoarding. The current work reviews some of the literature on the multifaceted nature of the human-animal relationship; describes the key role of empathy, attachment and anthropomorphism in human-animal relationships; seeks to depict how these psychological processes are distorted and dysfunctional in animal hoarding, with highly detrimental effects on both animal and human well-being.

Cognitive impairment in hoarding disorder: a systematic review

OBJECTIVE

In the present study, we aimed to perform a systematic review evaluating the cognitive performance of patients with hoarding disorder (HD) compared with controls. We hypothesized that HD patients would present greater cognitive impairment than controls.

METHODS

A systematic search of the literature using the electronic databases MEDLINE, SCOPUS, and LILACS was conducted on May 2020, with no date limit. The search terms were "hoarding disorder," "cognition," "neuropsychology," "cognitive impairment," and "cognitive deficit." We included original studies assessing cognitive functioning in patients with HD.

RESULTS

We retrieved 197 studies initially. Of those, 22 studies were included in the present study. We evaluated 1757 patients who were 41 to 72 years old. All selected studies comprised case-control studies and presented fair quality. Contrary to our hypothesis, HD patients showed impairment only in categorization skills in comparison with controls, particularly at confidence to complete categorization tasks. Regarding attention, episodic memory, working memory, information-processing speed, planning, decision-making, inhibitory control, mental flexibility, language, and visuospatial ability, HD patients did not show impairment when compared with controls. There is a paucity of studies on social cognition in HD patients, although they may show deficits. The impact of emotion in cognition is also understudied in HD patients.

CONCLUSION

Except for categorization skills, the cognitive performance in HD patients does not seem to be impaired when compared with that in controls. Further work is needed to explore social cognition and the impact of emotion in cognitive performance in HD patients.

The roles of intolerance of uncertainty, anxiety sensitivity and distress tolerance in hoarding disorder compared with OCD and healthy controls

BACKGROUND

It is suggested that the different psychological vulnerability factors of intolerance of uncertainty (IU), anxiety sensitivity (AS) and distress tolerance (DT) may be in important in hoarding disorder (HD). However, the extent to which these factors are specific to HD compared with other disorders remains unclear.

AIMS

The current study aimed to investigate differences in IU, AS and DT in three groups: HD (n=66), obsessive compulsive disorder (OCD; n=59) and healthy controls (HCs; n=63).

METHOD

Participants completed an online battery of standardised self-report measures to establish the independent variable of group membership (HD, OCD and HC) and the dependent variables (IU, AS and DT).

RESULTS

A MANOVA analysis indicated statistically significant differences in IU, AS and DT between the clinical groups and HCs. Follow-up analyses showed no statistically significant differences between the HD and OCD group for any of the three constructs. The results remained the same when examining the effects of co-morbid HD and OCD. An unexpected finding was the trend for IU, AS and DT to be more severe when HD and OCD were co-morbid.

CONCLUSIONS

The evidence suggests the absence of a specific relationship between IU, AS or DT in HD and instead is consistent with existing research which suggests that these psychological vulnerability factors are transdiagnostic constructs across anxiety disorders. The implications of the findings are discussed.

Subjective cognitive complaints and objective cognitive impairment in hoarding disorder

Individuals with Hoarding Disorder (HD) frequently complain of problems with attention and memory. These self-identified difficulties are often used as justification for saving and acquiring behaviors. Research using neuropsychological measures to examine verbal and visual memory performance and sustained attention have reported contradictory findings. Here we aim to determine the relationship between self-reported problems with memory and attention, objective memory and attention performance, and self-reported depression and anxiety symptoms in HD. Data was available for 319 individuals who participated in a treatment study of HD. Multiple regression was used to assess the relationship between self-reported complaints and objective measures, with age, education, and measures of depression and anxiety included as covariates. We found no association between self-reported memory difficulties and objective verbal or visual memory performance. Self-reported problems with attention were associated with objective attentional performance, although this relationship was partially accounted for by anxiety symptom severity. There was a small association between visual memory performance at baseline and improvements in hoardingrelated functional abilities following treatment. Improvements in subjective memory complaints pre-to-post treatment were associated with improvements in hoarding symptom severity and hoarding-related functioning. These results demonstrate a dissociation between perceived and objective functioning in HD.

Obsessive-Compulsive Disorder and Decision Making under Ambiguity: A Systematic Review with Meta-Analysis

In the last decade, decision-making has been proposed to have a central role in obsessive-compulsive disorder (OCD) aetiology, since patients show pathological doubt and an apparent inability to make decisions. Here, we aimed to comprehensively review decision making under ambiguity, as measured by the Iowa Gambling Task (IGT), in OCD, using a meta-analytic approach. According to PRISMA Guidelines, we selected 26 studies for a systematic review and, amongst them, 16 studies were included in a meta-analysis, comprising a total of 846 OCD patients and 763 healthy controls (HC). Our results show that OCD patients perform significantly lower than HC at the IGT, pointing towards the direction of a decision making impairment. In particular, this deficit seems to emerge mainly in the last three blocks of the IGT. IGT scores in OCD patients under the age of 18 were still significantly lower than in HC. Finally, no difference emerged between medicated and unmedicated patients, since they both scored significantly lower at the IGT compared to HC. In conclusion, our results are in line with the hypothesis according to which decision making impairment might represent a potential endophenotype lying between the clinical manifestation of OCD and its neurobiological aetiology.

Investigating executive functions in youth with OCD and hoarding symptoms

Executive functions (EF) deficits are hypothesized to be a core contributor to hoarding symptoms. EF have been studied in adult hoarding populations, but studies in youth are lacking. The current study compared multiple EF subdomains between youth with obsessive-compulsive disorder (OCD) and youth with OCD and hoarding symptoms. Forty youth (8-18 years old) with a primary diagnosis of OCD were recruited. Participants were divided by hoarding severity on the Child Saving Inventory (CSI) into either the "hoarding group" (upper 33.3%) or the "low-hoarding group" (lower 66.7%). Groups were compared on EF tasks of cognitive flexibility, decision-making, and inhibitory control. Youth in the hoarding group exhibited significantly higher cognitive flexibility and lowered perseveration than the low-hoarding group. Hoarding and low-hoarding groups did not differ in any other EF subdomain. Hoarding symptoms in youth with OCD were not associated with deficits in EF subdomains; instead, youth who hoard exhibited higher cognitive flexibility compared to youth with low hoarding symptoms.

Clinical characteristics of hoarding disorder in Japanese patients

Previous studies have reported clinical characteristics of hoarding disorder (HD), such as early onset, a chronic course, familiality, high unmarried rate, and high rates of comorbidities. However, clinical research targeting Japanese HD patients has been very limited. As a result, there is a low recognition of HD in Japan, leading to insufficient evaluation and treatment of Japanese HD patients.

The aim of the current study was to delineate the clinical characteristics of Japanese HD patients. Thirty HD patients, 20 obsessive-compulsive disorder (OCD) patients, and 21 normal controls (NC) were targeted in this study.

The HD group had a tendency toward higher familiality, earlier onset, and longer disease duration compared to the OCD group. In addition, the HD group showed a significantly higher unmarried rate than the NC group. The top two comorbidities in the HD group were major depressive disorder (56.7%) and attention-deficit/hyperactivity disorder (26.7%). The HD group had significantly higher scores on hoarding rating scales and lower scores on the Global Assessment of Functioning Scale than the other two groups.

The current study showed a clinical trend in Japanese HD patients similar to previous studies in various countries, suggesting that HD may be a universal disease with consistent clinical symptoms.

Differential patterns of brain activation between hoarding disorder and obsessive-compulsive disorder during executive performance

BACKGROUND

Preliminary evidence suggests that hoarding disorder (HD) and obsessive-compulsive disorder (OCD) may show distinct patterns of brain activation during executive performance, although results have been inconclusive regarding the specific neural correlates of their differential executive dysfunction. In the current study, we aim to evaluate differences in brain activation between patients with HD, OCD and healthy controls (HCs) during response inhibition, response switching and error processing.

METHODS

We assessed 17 patients with HD, 18 patients with OCD and 19 HCs. Executive processing was assessed inside a magnetic resonance scanner by means of two variants of a cognitive control protocol (i.e. stop- and switch-signal tasks), which allowed for the assessment of the aforementioned executive domains.

RESULTS

OCD patients performed similar to the HCs, differing only in the number of successful go trials in the switch-signal task. However, they showed an anomalous hyperactivation of the right rostral anterior cingulate cortex during error processing in the switch-signal task. Conversely, HD patients performed worse than OCD and HC participants in both tasks, showing an impulsive-like pattern of response (i.e. shorter reaction time and more commission errors). They also exhibited hyperactivation of the right lateral orbitofrontal cortex during successful response switching and abnormal deactivation of frontal regions during error processing in both tasks.

CONCLUSIONS

Our results support that patients with HD and OCD present dissimilar cognitive profiles, supported by distinct neural mechanisms. Specifically, while alterations in HD resemble an impulsive pattern of response, patients with OCD present increased error processing during response conflict protocols.

Cognitive performance of individuals with animal hoarding

BACKGROUND

The purpose of this study was to characterize the cognitive performance of individuals with animal hoarding.

METHODS

This is a cross-sectional study, in which 33 individuals between the ages of 29 to 84 (M = 61.39; SD = 12.69) with animal hoarding have been assessed. The participants completed a neurocognitive battery including measures of general cognitive functioning, visual memory and organization, verbal fluency, and verbal reasoning.

RESULTS

Data suggest that individuals with animal hoarding have high rates of cognitive deficits related to visual memory and verbal reasoning.

CONCLUSIONS

Based on the performance tests used, we can suggest the existence of cognitive difficulties related especially to the executive functions of individuals with animal hoarding in this sample.

Investigating behavior inhibition in obsessive-compulsive disorder: Evidence from eye movements

We investigated the role of inhibition failure in Obsessive Compulsive Disorder (OCD) through an eye tracking experiment. Twenty-five subjects with OCD were recruited, as well as 25 with Generalized Anxiety Disorder (GAD) and 25 healthy controls. A 3 (group: OCD group, GAD group and control group) × 2 (target eccentricity: far and near) × 2 (saccade task: prosaccade and antisaccade) mixed design was used, with all participants completing two sets of tasks involving both prosaccade (eye movement towards a target) and antisaccade (eye movement away from a target). The main outcome was the eye movement index, including the saccade latency (the time interval from the onset of the target screen to the first saccade) and the error rate of saccade direction. The antisaccade latency and antisaccade error rates for OCDs were much higher than those for GADs and healthy controls. OCDs had longer latency and error rates for antisaccades than for prosaccades, and for far-eccentricity rather than near-eccentricity stimuli. These results suggest that OCDs experience difficulty with behavior inhibition, and that they have higher visual sensitivity to peripheral stimuli. In particular, they show greatest difficulty in inhibiting behavior directed towards peripheral stimuli.

Psychological and electrophysiological indices of inattention in hoarding

Individuals with elevated hoarding symptoms report elevated symptoms of ADHD and these symptoms are related to impaired daily functioning. Neuropsychological studies have found specific deficits in attention, and a recent review of attentional data from numerous hoarding studies concluded that inattention likely represents an etiological factor in hoarding, rather than a comorbidity. Our study aimed to examine which symptoms of ADHD, inattention or hyperactivity, are related to hoarding symptom severity, and whether individuals with hoarding symptoms display a neurophysiological marker of poor attention (Theta/Beta Ratio; THBR) that might explain these associations. The THBR indexes theta power relative to beta power in the frontal cortex and is often atypical in individuals with ADHD. We hypothesised that individuals would report more severe problems with inattention and would exhibit an elevated theta/beta ratio relative to a healthy control group. We also predicted that any relationship between hoarding and inattention would be independent of anxiety and depression symptoms. 17 hoarding-symptomatic participants and 16 healthy control participants completed self-report measures relating to ADHD, hoarding and general psychopathology, and then underwent resting measures of electroencephalography (EEG). Individuals with hoarding symptoms reported greater difficulties with inattention and hyperactivity, however they did not exhibit an elevated theta/beta ratio. When taking into account recent anxiety and depression, only inattention predicted hoarding symptom severity. Further investigations may help clarify this association and help inform attention-based treatments for hoarding.

Deficits in physiological and self-conscious emotional response to errors in hoarding disorder

Hoarding disorder (HD) has been hypothesized to arise from deficits in error monitoring and abnormalities in emotional processing, but the relationship between error monitoring and emotional processing has not been examined. We examined measures of self-report, as well as behavioral, physiological, and facial responses to errors during a Stop-Change Task. 25 participants with HD and 32 healthy controls (HC) were recruited. Participants reported on number of errors committed and pre/post emotional response to errors. Skin conductance response (SCR) during correct and error commission trials was examined. Facial expression during task performance was coded for self-conscious and negative emotions. HD and HC participants had significantly different error rates but comparable error correction and post-error slowing. SCR was significantly lower for HD during error commission than for HC. During error trials, HD participants showed a significant deficit in displays of self-conscious emotions compared to HC. Self-reported emotions were increased in HD, with more negative and self-conscious emotion reported than was reported for HC participants. These findings suggest that hypoactive emotional responding at a physiological level may play a role in how errors are processed in individuals with HD.

ADHD and executive functioning deficits in OCD youths who hoard

Hoarding is common among youth with obsessive compulsive disorder (OCD), with up to 26% of OCD youth exhibiting hoarding symptoms. Recent evidence from adult hoarding and OCD cohorts suggests that hoarding symptoms are associated with executive functioning deficits similar to those observed in subjects with attention deficit hyperactivity disorder (ADHD). However, while hoarding behavior often onsets during childhood, there is little information about executive function deficits and ADHD in affected children and adolescents. The study sample included 431 youths (ages 6-17 years) diagnosed with OCD who participated in the OCD Collaborative Genetics Study and the OCD Collaborative Genetics Association Study and completed a series of clinician-administered and parent report assessments, including diagnostic interviews and measures of executive functioning (Behavior Rating Inventory of Executive Functioning; BRIEF) and hoarding severity (Hoarding Rating Scale-Interview; HRS-I). 113 youths (26%) had clinically significant levels of hoarding compulsions. Youths with and without hoarding differed significantly on most executive functioning subdomains and composite indices as measured by the parent-rated BRIEF. Groups did not differ in the frequency of full DSM-IV ADHD diagnoses; however, the hoarding group had significantly greater number of inattention and hyperactivity symptoms compared to the non-hoarding group. In multivariate models, we found that overall BRIEF scores were related to hoarding severity, adjusting for age, gender and ADHD symptoms. These findings suggest an association between hoarding and executive functioning deficits in youths with OCD, and assessing executive functioning may be important for investigating the etiology and treatment of children and adolescents with hoarding and OCD.

Comparison of brain activation patterns during executive function tasks in hoarding disorder and non-hoarding OCD

We examined differences in regional brain activation during tests of executive function in individuals with Hoarding Disorder (HD), Obsessive Compulsive Disorder (OCD), and healthy controls (HC) using functional magnetic resonance imaging (fMRI). Participants completed computerized versions of the Stroop and Go/No-Go task. We found that during the conflict monitoring and response inhibition condition in the Go/No-Go task, individuals with HD had significantly greater activity than controls in the anterior cingulate cortex (ACC) and right dorsolateral prefrontal cortex (DLPFC). HD also exhibited significantly greater right DLPFC activity than OCD. We also observed significant differences in activity between HD and HC and between HD and OCD in regions (ACC, anterior insula, orbitofrontal cortex, and striatum) involved in evaluating stimulus-response-reward associations, or the personal and task-relevant value of stimuli and behavioral responses to stimuli. These results support the hypothesis that individuals with HD have difficulty deciding on the value or task relevance of stimuli, and may perceive an abnormally high risk of negative feedback for difficult or erroneous cognitive behavior.

Stop Signal Reaction Time Deficits in a Lifetime Obsessive-Compulsive Disorder Sample

OBJECTIVES

Several studies have found impaired response inhibition, measured by a stop-signal task (SST), in individuals who are currently symptomatic for obsessive-compulsive disorder (OCD). The aim of this study was to assess stop-signal reaction time (SSRT) performance in individuals with a lifetime diagnosis of OCD, in comparison to a healthy control group. This is the first study that has examined OCD in participants along a continuum of OCD severity, including approximately half of whom had sub-syndromal symptoms at the time of assessment.

METHODS

OCD participants were recruited primarily from within the OCD clinic at a psychiatric hospital, as well as from the community. Healthy controls were recruited from the community. We used the stop signal task to examine the difference between 21 OCD participants (mean age, 42.95 years) and 40 healthy controls (mean age, 35.13 years). We also investigated the relationship between SST and measures of OCD, depression, and anxiety severity.

RESULTS

OCD participants were significantly slower than healthy controls with regard to mean SSRT. Contrary to our prediction, there was no correlation between SSRT and current levels of OCD, anxiety, and depression severity.

CONCLUSIONS

Results support prior studies showing impaired response inhibition in OCD, and extend the findings to a sample of patients with lifetime OCD who were not all currently above threshold for diagnosis. These findings indicate that response inhibition deficits may be a biomarker of OCD, regardless of current severity levels. (JINS, 2016, 22, 785-789).

Examining the Link Between Hoarding Symptoms and Cognitive Flexibility Deficits

Executive functioning deficits have been found to underlie primary symptoms of hoarding, such as difficulty discarding belongings and significant clutter. Cognitive flexibility-the ability to inhibit irrelevant material and attend flexibly between different mental sets-may be impaired as well, as individuals experience difficulty staying on task and are often distracted by specific possessions that tend to evoke an exaggerated emotional response. The present study investigated cognitive flexibility deficits via eye-tracking technology as a novel approach. Participants (N=69) with high and low self-reported hoarding symptoms were asked to respond to a series of auditory cues requiring them to categorize a small target number superimposed on one of three distractor image types: hoarding, nature, or a blank control. Across a range of behavioral and eye-tracking outcomes (including reaction time, accuracy rate, initial orientation to distractors, and viewing time for distractors), high hoarding participants consistently demonstrated greater cognitive inflexibility compared to the low hoarding group. However, high hoarding participants did not evidence context-dependent deficits based on preceding distractor types, as performance did not significantly differ as a function of hoarding versus nature distractors. Current findings indicate a pervasive, more global deficit in cognitive flexibility. Those with hoarding may encounter greater difficulty disengaging from previous stimuli and attending to a given task at hand, regardless of whether the context of the distractor is specifically related to hoarding. Implications and future directions for clarifying the nature of cognitive inflexibility are discussed.

PATTERNS OF CLINICALLY SIGNIFICANT COGNITIVE IMPAIRMENT IN HOARDING DISORDER

OBJECTIVES

The cognitive characteristics of individuals with hoarding disorder (HD) are not well understood. Existing studies are relatively few and somewhat inconsistent but suggest that individuals with HD may have specific dysfunction in the cognitive domains of categorization, speed of information processing, and decision making. However, there have been no studies evaluating the degree to which cognitive dysfunction in these domains reflects clinically significant cognitive impairment (CI).

METHODS

Participants included 78 individuals who met DSM-V criteria for HD and 70 age- and education-matched controls. Cognitive performance on measures of memory, attention, information processing speed, abstract reasoning, visuospatial processing, decision making, and categorization ability was evaluated for each participant. Rates of clinical impairment for each measure were compared, as were age- and education-corrected raw scores for each cognitive test.

RESULTS

HD participants showed greater incidence of CI on measures of visual memory, visual detection, and visual categorization relative to controls. Raw-score comparisons between groups showed similar results with HD participants showing lower raw-score performance on each of these measures. In addition, in raw-score comparisons HD participants also demonstrated relative strengths compared to control participants on measures of verbal and visual abstract reasoning.

CONCLUSIONS

These results suggest that HD is associated with a pattern of clinically significant CI in some visually mediated neurocognitive processes including visual memory, visual detection, and visual categorization. Additionally, these results suggest HD individuals may also exhibit relative strengths, perhaps compensatory, in abstract reasoning in both verbal and visual domains.

Neurocognitive performance in unmedicated patients with hoarding disorder

OBJECTIVE

Hoarding disorder (HD) is an often incapacitating psychiatric illness associated with a wide range of neurocognitive abnormalities. Some prior neuropsychological studies have found executive dysfunction in HD, but no clear pattern has emerged. One potential reason for discrepant results in previous studies might be the inclusion of patients on psychotropic and other medications that can affect neurocognitive performance. Therefore, we examined neurocognitive functioning in medication-free HD patients. We also added a novel investigation of implicit learning, which has been found to be abnormal in obsessive-compulsive disorder (OCD) and related disorders.

METHOD

Twenty-six participants meeting the Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5; American Psychiatric Association, 2013) diagnostic criteria for HD and 23 normal controls were administered a battery of neuropsychological tests and symptom rating scales. All participants were free of psychotropic medications for at least 6 weeks prior to the study.

RESULTS

HD participants showed no significant differences from normal controls on measures of verbal memory, attention, or executive functioning, including response inhibition, planning, organization, and decision making. However, HD participants demonstrated a trend toward less implicit learning and greater use of explicit learning strategies during perceptual categorization compared to normal controls. HD participants who used an implicit strategy performed significantly worse than controls who used an implicit strategy. Hoarding symptom severity was not associated with neurocognitive performance.

CONCLUSIONS

HD patients may have a tendency to use explicit rather than implicit learning strategies for perceptual categorization but perform as well as normal controls on many other neurocognitive measures. Future studies should assess unmedicated participants and examine test strategies, not just outcomes.

A case of digital hoarding

A 47-year-old man presented to our outpatient clinic, preoccupied with hoarding of digital pictures, which severely interfered with his daily functioning. He was formerly diagnosed with autism and hoarding of tactile objects. As of yet, digital hoarding has not been described in the literature. With this case report, we would like to introduce 'digital hoarding' as a new subtype of hoarding disorder. We conclude with differential diagnostic considerations and suggestions for treatment.

Poor Memory Confidence Mediates the Association between Inattention Symptoms and Hoarding Severity and Impairment

Hoarding disorder (HD) is characterized by excessive saving and difficulty discarding possessions, which results in severe clutter and functional impairment. HD shows patterns of elevated comorbidity with the inattentive subtype of attention deficit-hyperactivity disorder (ADHD-I). ADHD-I symptoms are associated with more severe HD pathology (Tolin & Villavicencio, 2011), but the mechanisms underlying this association are unclear. The present study used serial mediation analyses in a sample of individuals with HD (n = 32) and healthy controls (n = 26) to test one potential pathway: ADHD-I symptoms lead to poor memory confidence, which leads to excessive saving of possessions to facilitate remembering, which in turn leads to clutter and corresponding functional impairment. The model provided a strong fit for the data, accounting for over 90% of the variance in functional impairment. Alternate models that did not include ADHD-I symptoms and poor memory confidence provided a weaker fit. These findings support and extend leading cognitive-behavioral conceptualizations of HD (e.g., Frost & Hartl, 1996) and point to inattention symptoms and memory confidence as potential targets for HD prevention and intervention research.

Evaluating effect of symptoms heterogeneity on decision-making ability in obsessive-compulsive disorder

AIMS

Despite having a univocal definition, obsessive-compulsive disorder (OCD) shows a remarkably phenotypic heterogeneity. The published reports show impaired decision-making in OCD patients, using tasks such as the Iowa Gambling Task (IGT). We wanted to verify the hypothesis of an IGT worse performance in a large sample of OCD patients and healthy control (HC) subjects and to examine the relation between neuropsychological performance in IGT and the OCD symptoms heterogeneity.

METHODS

Binary data from the Yale-Brown Obsessive Compulsive Scale collected on a large sample of OCD patients were analyzed using a multidimensional item response theory model to explore the underlying structure of data, thus revealing latent factors. Factor scores were categorized into quartiles. Then, for each factor, we identified patients respectively with the highest versus lowest score. We evaluated whether symptom dimensions affect the probability of a correct answer over time generalized, during IGT performance, fitting a generalized linear mixed model.

RESULTS

We found a general deficit in ambiguous decision-making in OCD compared to HC. Moreover, our findings suggested that OCD symptoms heterogeneity affects decision-making learning abilities during IGT. In fact, while 'Symmetry' and 'Washing' patients showed a learning curve during the task, other subgroups did not.

CONCLUSIONS

Our study confirmed previous findings suggesting that OCD is characterized by a deficit in decision-making under uncertainty. Moreover, our study gave evidence about biological specificity for each symptom dimension in OCD. Data were discussed in the context of the somatic marker hypothesis, which was hypothesized to be reduced in OCD patients.

Neuropsychological and neurophysiological insights into hoarding disorder

Hoarding disorder (HD) is associated with significant personal impairment in function and constitutes a severe public health burden. Individuals who hoard experience intense distress in discarding a large number of objects, which results in extreme clutter. Research and theory suggest that hoarding may be associated with specific deficits in information processing, particularly in the areas of attention, memory, and executive functioning. There is also growing interest in the neural underpinnings of hoarding behavior. Thus, the primary aim of this review is to summarize the current state of evidence regarding neuropsychological deficits associated with hoarding and review research on its neurophysiological underpinnings. We also outline the prominent theoretical model of hoarding and provide an up-to-date description of empirically based psychological and medical treatment approaches for HD. Finally, we discuss important future avenues for elaborating our model of HD and improving treatment access and outcomes for this disabling disorder.

Review of cognitive performance in hoarding disorder

Hoarding disorder is characterized by extreme difficulty letting go of objects other people would routinely discard or give away, such that the home becomes dysfunctionally cluttered with possessions. Specific cognitive processes, such as decision-making, categorization, and attention, have been hypothesized to contribute to the overvaluing of objects. This review synthesizes the evidence related to those propositions and other executive functioning processes that have received research attention. In this paper, we are primarily interested in cognitive processes that can be, but are not always, studied using performance tasks. Compared to both healthy controls and clinical controls, participants with clinical levels of compulsive hoarding show replicable performance deficits in several areas: planning/problem-solving decisions, visuospatial learning and memory, sustained attention/working memory, and organization. Categorization/concept formation, visuospatial processing, and inhibitory control require further investigation and more detailed testing methods to address inconsistencies in reported findings. Many studies fail to account for potential confounds presented by comorbid depression and between-group differences in age, a problem that should be rectified in future research on this topic. The article concludes with recommendations for a research agenda to better understand contributors to abnormal valuing of objects in hoarding disorder.

The profile of executive function in OCD hoarders and hoarding disorder

Hoarding disorder is a new mental disorder in DSM-5. It is classified alongside OCD and other presumably related disorders in the Obsessive-Compulsive and Related Disorders chapter. We examined cognitive performance in two distinct groups comprising individuals with both OCD and severe hoarding, and individuals with hoarding disorder without comorbid OCD. Participants completed executive function tasks assessing inhibitory control, cognitive flexibility, spatial planning, probabilistic learning and reversal and decision making. Compared to a matched healthy control group, OCD hoarders showed significantly worse performance on measures of response inhibition, set shifting, spatial planning, probabilistic learning and reversal, with intact decision making. Despite having a strikingly different clinical presentation, individuals with only hoarding disorder did not differ significantly from OCD hoarders on any cognitive measure suggesting the two hoarding groups have a similar pattern of cognitive difficulties. Tests of cognitive flexibility were least similar across the groups, but differences were small and potentially reflected subtle variation in underlying brain pathology together with psychometric limitations. These results highlight both commonalities and potential differences between OCD and hoarding disorder, and together with other lines of evidence, support the inclusion of the new disorder within the new Obsessive-Compulsive and Related Disorders chapter in DSM-5.

The synergistic effect of growing older with hoarding behaviors

Clinically significant hoarding behaviors (HB) have been defined as acquisition of, and failure to discard, large numbers of items, which limits the use of one's home and causes functional impairment or distress. HB disproportionally affect adults aged 55 and older, and although research on HB has accelerated in the past decade, few studies focus on older adults. This qualitative study, based on grounded theory methodology, utilized interview data from 22 older adults with HB to understand the dynamic interaction between HB and the aging process. Participants described the specific ways that their chronic HB were complicated by changes in their health status, social context, and home setting, resulting in greater functional impairment and distress. By identifying these changes that commonly occur with age and their synergistic relationship with HB, nurses and other health professionals can develop targeted interventions to improve home safety and support the independence of these older adults.

A Multitrait-Multimethod Matrix Investigation of Hoarding

Hoarding is a serious and potentially life-threatening mental health problem that, until recently, was considered a subtype of OCD. However, recent research suggests it is distinct and more prevalent than OCD. Three key defining features have emerged in factor analytic studies of hoarding scales: excessive acquisition, difficulty discarding, and excessive clutter. Covariation among these defining features has received limited attention. The primary aim of the current study was to examine the role of the three key features in defining hoarding disorder. Convergent and discriminant validity of the three hoarding factors were examined in a multitrait-multimethod matrix. A secondary aim was to examine the extent to which each hoarding feature distinguished individuals meeting criteria for hoarding from those with OCD and community controls. Although the three-factor model provided an adequate fit for the data and convergent validities were high, the hoarding factors evidenced poor discriminant validity across measures. The findings provide preliminary support for a more parsimonious merging of the clutter, acquisition, and discarding subscales versus parsing out subscale scores. Specifically, the active acquisition of items, buildup of clutter, and difficulty discarding accumulated possessions co-occurred strongly enough to be considered a unidimensional construct. Thus, these symptoms were less attributable to separate phenomena and better conceived as part of a cohesive hoarding phenotype. Each of the three factors discriminated hoarding participants from OCD patients and community controls, but did not discriminate the latter two groups. The findings have implications for treating acquisition as a specifier in DSM-5.