Organizational strategies mediate nonverbal memory impairment in obsessive-compulsive disorder

Situation awareness in obsessive-compulsive disorder

Past studies have suggested that OCD patients suffer memory impairment on tasks using complex stimuli that require memory for combined elements to be maintained, but not for more simplistic memory tests. We tested this with 42 OCD patients and 42 healthy controls performed a computerized situation awareness task. In addition, participants completed the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) and Maudsley Obsessive-Compulsive Inventory (MOCI). The OCD patients had poorer accuracy in integration/comprehension and perception levels than controls. There were significant correlations between situational awareness scores (i.e., visuo-spatial monitoring and processing) and Y-BOCS obsession-compulsion and slowness and doubt scores of MOCI in OCD patients. In addition, there were also significant correlations between situational awareness and controlling, cleaning, slowness, rumination and total scores of MOCI in control group. Results indicated that (I) OCD patients have problems of perception, integration, and comprehension of complex visual perceptions; (II) situation awareness deficits associated with severity and prevalence of obsessions and compulsions.

A review of cognitive neuropsychiatry in the taxonomy of eating disorders: state, trait, or genetic?

A greater understanding of neuropsychological traits in eating disorders may help to construct a more biologically based taxonomy. The aim of this paper is to review the current evidence base of neuropsychological traits in people with eating disorders. Evidence of difficulties in set shifting, weak central coherence, emotional processing difficulties, and altered reward sensitivity is presented for people both in the acute and recovered phase of the illness. These traits are also seen in first degree relatives. At present there is limited research linking these neuropsychological traits with genetic and neuroanatomical measures. In addition to improving the taxonomy of eating disorders, neuropsychological traits may be of value in producing targeted treatments.

Neuropsychological functioning in obsessive-compulsive disorder: are executive functions the key deficit?

OBJECTIVE

Although several studies have examined neuropsychological functions in obsessive-compulsive disorder (OCD), findings are not conclusive, predominantly due to small samples and assessment of limited domains. We aim to map the neuropsychological profile of OCD in a large sample with a comprehensive battery of tests.

METHOD

Neuropsychological functions were tested in 150 subjects with DSM-IV OCD and 205 healthy control subjects.

RESULTS

Subjects with OCD performed significantly worse than healthy control subjects on Colour Trails 1 time, Tower of Hanoi 3-disk time, Wisconsin Card Sorting Test categories completed, Iowa Gambling Task, Complex Figure Test immediate and delayed recall (p<0.001).

CONCLUSIONS

Subjects with OCD evince deficits in scanning, planning time, concept formation, decision making and encoding of non-verbal memory after controlling for the effects of age, gender and education. The profile is suggestive of a predominantly executive dysfunction, with difficulties in strategizing and organizing stimuli and cognitive resources for maximum efficiency. The findings implicate dorsolateral prefrontal, superior medial prefrontal and anterior cingulate cortices, suggesting that OCD might not be a purely orbitofronto-striatal disorder as previously conceptualized.

Correlation between insight dimensions and cognitive functions in patients with deficit and nondeficit schizophrenia

Previous studies have shown correlations between poor insight and neurocognitive impairment in schizophrenia. Deficit schizophrenia has been associated with worse cognitive functioning and poorer insight. This study aimed at investigating the relationship between insight dimensions (measured by Schedule for the Assessment of Insight-Expanded Version and its factors) and specific neurocognitive functions (assessed through a battery of neuropsychological tests) considering separately patients with deficit (n=29) and nondeficit schizophrenia (n=44), categorized according to the Schedule for the Deficit Syndrome. We found that working memory correlated positively and significantly with awareness of mental illness in both groups. In nondeficit group, awareness of mental illness correlated additionally with verbal fluency and attention. If confirmed by further studies, these results may have important consequences, such as the need of tailoring differently cognitive rehabilitation for each group.

Neuropsychological deficits in drug naïve, non-depressed obsessive-compulsive disorder patients

There are several studies that compared neuropsychological performance of OCD patients with healthy controls. However, there are hardly any studies which have used drug-naïve as well as non-depressed OCD subjects in their studies. The present study compared eighteen drug-naïve non-depressed OCD patients with similar number of age, education and sex matched healthy controls on neuropsychological tests. The tests used are block design, object assembly, Visuospatial Working Memory Test, Verbal Working Memory Test, Complex Figure Test, Stroop Test and Wisconsin Card Sorting Test. In addition to usual significance testing, Effect Sizes were calculated. In addition, correlation was done between neuropsychological test variables and clinical variables. The results did not show any significant correlation between any of the clinical variables and neuropsychological test variables. On the other hand, patients showed significant deficits mainly in executive functions and organizational strategy with respect to visuospatial functions. The observed deficits can be attributed to both dorsolateral prefrontal cortex and orbitofrontal cortex involvement.

Association between cerebral metabolism and Rey-Osterrieth Complex Figure Test performance in Alzheimer's disease

The copy condition of the Rey-Osterrieth Complex Figure (ROCF) is sensitive to Alzheimer's disease (AD) pathology, but its neural correlates remain unclear. We used fluorodeoxyglucose positron emission tomography (FDG-PET) to elucidate this association in 77 patients with probable AD. We observed a correlation between ROCF and metabolic rate of bilateral temporal-parietal cortex and occipital lobe, and right frontal lobe. Global and local elements of the ROCF correlated with metabolic rate of these same regions. The copy approach correlated with right lateral temporal cortex. The ROCF appears reflective of posterior temporal-parietal cortex functioning, highlighting the role of visuospatial processing in constructional abilities in AD.

Global processing training to improve visuospatial memory deficits after right-brain stroke

Visuospatial stimuli are normally perceived from the global structure to local details. A right-brain stroke often disrupts this perceptual organization, resulting in piecemeal encoding and thus poor visuospatial memory. Using a randomized controlled design, the present study examined whether promoting the global-to-local encoding improves retrieval accuracy in right-brain-damaged stroke survivors with visuospatial memory deficits. Eleven participants received a single session of the Global Processing Training (global-to-local encoding) or the Rote Repetition Training (no encoding strategy) to learn the Rey-Osterrieth Complex Figure. The result demonstrated that the Global Processing Training significantly improved visuospatial memory deficits after a right-brain stroke. On the other hand, rote practice without a step-by-step guidance limited the degree of memory improvement. The treatment effect was observed both immediately after the training procedure and 24 h post-training. Overall, the present findings are consistent with the long-standing principle in cognitive rehabilitation that an effective treatment is based on specific training aimed at improving specific neurocognitive deficits. Importantly, visuospatial memory deficits after a right-brain stroke may improve with treatments that promote global processing at encoding.

Central coherence in full recovery of anorexia nervosa

OBJECTIVE

This study examined central coherence as a possible endophenotype in a large sample of women recovered from anorexia nervosa (rec AN). Recovery was defined by considering physiological, behavioural and psychological variables.

METHOD

A total of 100 rec AN women and 100 healthy women completed the Rey Complex Figure Test, a measure for visual-spatial central coherence. The participants were matched 1:1 for age and educational level.

RESULTS

Compared with the healthy control group, the rec AN group showed better accuracy in the copy condition. There was a trend for a local strategy in the rec AN group compared with a global strategy in the healthy control group.

CONCLUSIONS

This sample of rec AN women showed no inefficiencies in global processing but a superior local processing after full recovery from AN.

Antisaccade performance in patients with obsessive-compulsive disorder and unaffected relatives: further evidence for impaired response inhibition as a candidate endophenotype

Cognitive dysfunctions such as inhibitory deficits and visuospatial abnormalities are often found in patients with obsessive-compulsive disorder (OCD). Recent findings in unaffected relatives indicate that response inhibition and other neuropsychological functions may also constitute endophenotypes of OCD. In the present study, 30 OCD patients, 30 first-degree relatives, and 30 healthy control subjects were assessed using a comprehensive neuropsychological test battery. A subsample of 21 subjects of each group also performed an antisaccade task. The samples were matched according to age, gender, education, and verbal intelligence. The OCD patients and the unaffected OCD relatives showed increased antisaccade error rates compared with the healthy control group (p = 0.003, p = 0.028, respectively). Significantly prolonged antisaccade latencies as compared to prosaccade latencies were only found in the OCD patients compared with the healthy control group (p = 0.019). Only OCD patients but not the unaffected OCD relatives were impaired with regard to visuospatial functions, problem-solving, and processing speed. Antisaccade errors did not correlate with severity of OCD or depressive symptoms. This study confirms inhibitory deficits, as indicated by increased antisaccade error rates, as a candidate endophenotype of OCD. In agreement with previous findings from imaging studies, our data suggest that functional abnormalities in frontostriatal and parietal cortical regions form part of the vulnerability for OCD.

The extended fronto-striatal model of obsessive compulsive disorder: convergence from event-related potentials, neuropsychology and neuroimaging

In this work, we explored convergent evidence supporting the fronto-striatal model of obsessive-compulsive disorder (FSMOCD) and the contribution of event-related potential (ERP) studies to this model. First, we considered minor modifications to the FSMOCD model based on neuroimaging and neuropsychological data. We noted the brain areas most affected in this disorder -anterior cingulate cortex (ACC), basal ganglia (BG), and orbito-frontal cortex (OFC) and their related cognitive functions, such as monitoring and inhibition. Then, we assessed the ERPs that are directly related to the FSMOCD, including the error-related negativity (ERN), N200, and P600. Several OCD studies present enhanced ERN and N2 responses during conflict tasks as well as an enhanced P600 during working memory (WM) tasks. Evidence from ERP studies (especially regarding ERN and N200 amplitude enhancement), neuroimaging and neuropsychological findings suggests abnormal activity in the OFC, ACC, and BG in OCD patients. Moreover, additional findings from these analyses suggest dorsolateral prefrontal and parietal cortex involvement, which might be related to executive function (EF) deficits. Thus, these convergent results suggest the existence of a self-monitoring imbalance involving inhibitory deficits and executive dysfunctions. OCD patients present an impaired ability to monitor, control, and inhibit intrusive thoughts, urges, feelings, and behaviors. In the current model, this imbalance is triggered by an excitatory role of the BG (associated with cognitive or motor actions without volitional control) and inhibitory activity of the OFC as well as excessive monitoring of the ACC to block excitatory impulses. This imbalance would interact with the reduced activation of the parietal-DLPC network, leading to executive dysfunction. ERP research may provide further insight regarding the temporal dynamics of action monitoring and executive functioning in OCD.

Neuropsychological study of patients with obsessive-compulsive disorder and their parents in China: searching for potential endophenotypes

OBJECTIVE

The existence of neuropsychological deficits has been implicated in obsessive-compulsive disorder (OCD), particularly memory, attention, and executive functions. However, few studies have focused on neuropsychological deficits in the relatives of OCD patients. The aim of this study was to investigate cognitive deficits in OCD patients and their parents.

METHODS

Forty patients with OCD, 48 parents of these patients, and 87 healthy controls completed a neuropsychological testing battery.

RESULTS

Both OCD patients and their parents showed impairments in delayed verbal memory and delayed visual memory. Furthermore, they performed worse than healthy controls in problem-solving ability.

CONCLUSION

Our study demonstrated familial aggregation of delayed memory deficits and impaired problem-solving ability, which may be the potential neuropsychological endophenotypes of hereditary susceptibility to OCD.

Neuropsychological correlates of insight in obsessive-compulsive disorder

OBJECTIVE

There are limited data on neuropsychological correlates of poor insight in obsessive-compulsive disorder (OCD). We hypothesize that poor insight may be associated with greater impairment in tasks of conflict resolution/response inhibition and possibly impairment in a task of verbal learning and memory.

METHOD

Insight and neuropsychological functions were assessed in 150 subjects with DSM-IV OCD. The neuropsychological data of 177 healthy control subjects were used for comparison.

RESULTS

Insight score correlated significantly with the Stroop Interference Test for conflict resolution/response inhibition (P = 0.002), and showed trends for significance with the Controlled Oral Word Association (COWA) average for verbal fluency (P = 0.021) and delayed recall on the Auditory Verbal Learning Test (AVLT) for verbal memory (P = 0.015). On regression analysis, the AVLT delayed recall, the COWA average, the Matrix score, the Yale-Brown Obsessive-Compulsive Scale total score, and current antipsychotic use emerged as significant predictors of poorer insight.

CONCLUSION

Poor insight is associated with greater impairments in conflict resolution/response inhibition, verbal memory, and fluency. Individuals with poorer insight may have difficulty in appropriately processing conflicting information, updating their memory with corrective information, and then accessing this corrective information to modify their irrational beliefs.

Pathogenetic and therapeutic perspectives on neurocognitive models in psychiatry: A synthesis of behavioral, brain imaging, and biological studies

Neurocognitive assessments are useful to determine the locus of insult as well as functional capacities of patients on treatment. In psychiatry, neurocognitive assessment is useful in the identification of brain lesions, evaluation of cognitive deterioration over time, and advancement of theories regarding the neuroanatomical localization of symptoms. Neurocognitive models provide a bridging link between brain pathology and phenomenology. They provide a useful framework to understand the pathogenesis of psychiatric disorders, bringing together isolated findings in behavioral, neuroimaging, and other neurobiological studies. This review will discuss neurocognitive model of three disorders - schizophrenia, bipolar disorder, and obsessive compulsive disorder - by incorporating findings from neurocognitive, neuroimaging, and other biological studies.

Impaired body but not face perception in patients with obsessive-compulsive disorder

BACKGROUND

Empirical evidence involving the processing of social information by patients with obsessive-compulsive disorder (OCD) has been relatively scarce. Our study investigated the perceptual abilities of patients with OCD to recognize human faces and bodies.

METHOD

Fifty-four drug-free or drug-naïve patients with OCD and 42 healthy controls performed discrimination tasks consisting of four types of stimuli: two sets of faces that were manipulated with regard to configuration and features, human bodies, and chairs. The stimuli were presented in upright and upside-down orientations.

RESULTS

Patients with OCD were significantly less accurate in discriminating pairs of bodily postures implying actions. However, we found no significant differences between patient and control groups in the ability to recognize faces and chairs. The inversion effects for bodies and faces were also comparable between the two groups.

CONCLUSIONS

The current findings suggest that patients with OCD experience difficulty in perceiving static forms of bodily postures, but are able to adequately recognize human faces. Our data indicate a selective deficit in the perception of bodily postures in those with OCD and suggest that this deficit is probably not related to the abnormal configurational processing of social objects.

A video ethnography approach for linking naturalistic behaviors to research constructs of neurocognition in schizophrenia

Few methods are available to explore the impact of neurocognition in schizophrenia on behaviors performed in usual contexts. The authors developed a video ethnography approach to examine the relationship between naturalistic behaviors and research constructs of neurocognition. Video ethnographers accompanied subjects through usual routines gathering continuous video data. Researchers developed codes to measure four behavioral domains observed on video. This paper describes the psychometric characteristics to be considered in the development of observational approaches. It also highlights differences between behaviors performed in usual environments and neuropsychological constructs. The authors demonstrate that everyday behaviors that have been shown to correspond to neurocognitive skills in a pilot feasibility study can be identified and rated. They further suggest that observational methods could provide novel strategies for linking research findings and clinical concerns.

Memory dysfunction in panic disorder: an investigation of the role of chronic benzodiazepine use

BACKGROUND

Studies of the neurocognitive effects of long-term benzodiazepine use have been confounded by the presence of neurocognitive deficits characterizing the clinical conditions for which these medications are taken. Similarly, studies of the neurocognitive effects of anxiety disorders have been confounded by the inclusion of chronically benzodiazepine-medicated patients. This study was designed to tease apart the potentially confounding effects of long-term benzodiazepine use and panic disorder (PD) on memory and visuoconstructive abilities.

METHODS

Twenty chronically benzodiazepine-medicated and 20 benzodiazepine-free patients with PD with agoraphobia were compared with a group of 20 normal control participants, group-matched for age, education, and gender on a battery of neuropsychological tests assessing short-term, episodic long-term, and semantic memory, as well as visuoconstructive abilities.

RESULTS

Results indicated that benzodiazepine-free panic patients were relatively impaired in nonverbal short-term and nonverbal episodic long-term memory and visuoconstructive abilities, whereas verbal short-term and verbal episodic memory and semantic memory were preserved. Only limited evidence was found for more pronounced impairments in chronically benzodiazepine-medicated PD patients.

CONCLUSIONS

This study provides evidence that patients with PD are characterized by relative impairments in nonverbal memory and visuoconstructive abilities, independent of benzodiazepine use. Nonetheless, we found evidence that chronic treatment with benzodiazepines is associated with intensification of select relative impairments in this realm. Documentation of these deficits raises questions about the broader etiology of neurocognitive impairment in PD as well as its impact on daily functioning.

Neuropsychological functioning in hoarding disorder

Hoarding disorder (HD) is increasingly viewed as distinct from obsessive-compulsive disorder (OCD). In particular, some researchers have suggested that HD is characterized by substantial problems of neurocognitive function; however, HD patients have not yet been compared to OCD patients in this respect. The aim of the present study was to compare neuropsychological test performance in HD patients (n=27), OCD patients (n=12), and healthy controls (n=26). Consistent with previous research, HD patients showed an attenuated ability to sustain attention and poorer employment of adaptive memory strategies compared to healthy controls. HD and OCD patients did not differ significantly on these measures, although moderate effect sizes suggested that hoarders showed somewhat greater attenuation of attentional capacity. Rates of true impairment on any particular neuropsychological test were fairly low across all three groups, although 67% of HD patients (compared to 58% of OCD patients and 42% of healthy controls) scored in the impaired range on at least one measure (odds ratio=2.22). Results are discussed in terms of emerging conceptualizations of HD as a distinct illness.

Olfactory identification and discrimination in obsessive-compulsive disorder

BACKGROUND

Neuroimaging and neuropsychological data from patients with an obsessive-compulsive disorder (OCD) indicate the dysfunction of the orbitofrontal cortex (OFC). Olfactory processing has been associated with OFC function, although results from OCD studies regarding this sensory modality have been inconclusive. No previous study has analyzed both odor discrimination and identification capacity in OCD patients using "Sniffin' Sticks" tests. The aim of our study was to assess odor threshold, identification, discrimination, and nonverbal memory in OCD patients, in order to determine whether these functions were affected.

METHODS

Olfactory function was measured in 29 OCD patients and 29 healthy volunteers (HV) using the "Sniffin' Sticks" test and their nonverbal memory was scored with the Rey-Osterrieth Complex Figure Test.

RESULTS

OCD patients showed significant impairment in their odor performance and in their execution of the nonverbal memory task compared to HV. No statistical associations were found between the deficits in the two areas. The severity of depressive and obsessive-compulsive symptoms did correlate with olfactory identification.

CONCLUSION

Our findings support the hypothesis that olfactory and memory dysfunctions in OCD reflect different neurobiological alterations of the disorder, and point to the modulation effect of depressive and obsessive-compulsive symptoms on odor performance.

Poor fine-motor and visuospatial skills predict persistence of pediatric-onset obsessive-compulsive disorder into adulthood

BACKGROUND

Half of pediatric-onset OCD cases remit by adulthood. Studies have demonstrated that initial response to pharmacotherapy, age of onset, prominent hoarding symptoms, and the presence of comorbid tic disorders are associated with long-term outcome. Our goal was to examine the association between childhood performance on neuropsychological testing and persistence of OCD into adulthood.

METHODS

Twenty-four children with OCD were followed for an average of 7.5 years into early adulthood. Neuropsychological performance in childhood (<16 years) was measured. The battery included the Wechsler Intelligence Scale for Children (WISC-III), the Purdue pegboard test, the Rey-Osterreith Complex Figure Task (RCFT) and the Beery-Buktenica test of Visual Motor Integration (VMI). We hypothesized that deficits in fine-motor skills, visuospatial skills, and nonverbal memory as well as overall intelligence would be associated with adulthood outcome. We used a Cox proportional hazard model of survival analysis in which time to remission of OCD symptoms was the main outcome variable.

RESULTS

Poor childhood performance on the Purdue pegboard task and the block design subscale of WISC-III was associated with persistence of OCD symptoms into adulthood. IQ, VMI, and nonverbal memory performance did not predict significantly the persistence of OCD.

CONCLUSIONS

These results suggest that visuospatial and fine-motor skill deficits are predictive of poor long-term outcome in pediatric-onset OCD. Future longitudinal studies are needed to chart the course of these deficits relative to the course of symptoms in OCD and to determine whether the association of these neuropsychiatric deficits with long-term outcome is specific to pediatric-onset OCD or generalizes to other psychiatric disorders.

Study of neurocognitive endophenotypes in drug-naïve obsessive-compulsive disorder patients, their first-degree relatives and healthy controls

OBJECTIVE

Obsessive-compulsive disorder (OCD) is a debilitating heritable neuropsychiatric condition. Attempts to delineate genetic contributions in OCD have met with limited success, with an ongoing search for neurocognitive endophenotypes. In this study, an attempt has been made to study and compare the neurocognitive functioning of patients with OCD, their first-degree relatives (FDRs) and healthy controls.

METHOD

A cross-sectional design study was carried out with thirty dyads of patients with OCD, their FDRs and thirty matched healthy controls and screened using Mini International Neuropsychiatric Interview, Verbal Adult Intelligence Scale, Yale Brown Obsessive-Compulsive Scale, Montgomery Åsberg Depression Rating Scale, International Personality Disorder Examination (Anankastic personality scale).Tests of National Institute of Mental Health and Neurosciences Neuropsychological Battery were used to assess domains of attention, verbal memory, visual memory, set-shifting, response inhibition, planning and visuoconstructive abilities. spss version 14.0 was used for descriptive and analytical data analysis.

RESULTS

There were no statistically significant differences between patients with OCD and their FDRs on neurocognitive domains of delayed verbal recall, set-shifting, response inhibition and visuoconstructive abilities (P > 0.05) which were impaired compared with healthy controls. Significant differences (P < 0.05) on domains of attention, planning time and visual memory were noted between FDRs and patients.

CONCLUSION

The present study supports set-shifting and inhibitory control and proposes visuoconstructive abilities and delayed verbal recall as potential endophenotypes for OCD.

The ecological validity of the Rey-Osterrieth Complex Figure: predicting everyday problems in children with neuropsychological disorders

Despite its extensive use, the validity of the Rey Complex Figure in predicting everyday behavioral executive dysfunction displayed by children with various neuropsychological disorders is unknown. The copied figures of 263 children aged 6 to 17 years were rescored using an accuracy approach that measured visuospatial ability and three process approaches developed to measure executive functioning. Controlling for age and IQ, partial correlations between scores derived by all scoring methods and the parent ratings on an executive function inventory were zero. In contrast, all four scoring approaches were associated with parent ratings on questionnaires that indexed children's academic achievement, developmental status, and adaptive ability. The findings suggest that the ecological validity of the Rey Complex Figure for children with various central nervous system disorders is more associated with visual-motor integration skills than executive functioning.

Distinct neuropsychological profiles of three major symptom dimensions in obsessive-compulsive disorder

Recent neuroimaging studies have suggested that different symptom dimensions are mediated by partially distinct neural systems in obsessive-compulsive disorder (OCD). However, the correlations between neuropsychological profiles and symptom dimensions in OCD are unknown. The aim of this study was to examine the extent to which OCD symptom dimensions were associated with episodic memory and attention and executive functions. The symptom dimensions of 63 patients with OCD were assessed using both the Padua Inventory and the Y-BOCS symptom checklist. Then, we administered the Logical Memory (LM) subset of the Wechsler Memory Scale-Revised (WMR-R) test and evaluated inhibition (Stroop test, Trail Making test) and cognitive flexibility (Digit Symbol test, Letter Fluency, and Category Fluency). While associations were observed between scores on the contamination/cleaning dimension and better performances on the LM and Trail Making tests, associations were also observed between scores on the aggressive/checking dimension and poorer performances on the Trail Making test. In addition, we found that scores on the symmetry/ordering dimension were associated with poorer performances on the LM and Trail Making tests. Our results support the hypothesis that different symptoms may represent distinct and partially overlapping neurocognitive networks in OCD patients.

Impaired executive functioning in subclinical compulsive checking with ecologically valid stimuli in a working memory task

We previously showed that working memory (WM) performance of subclinical checkers can be affected if they are presented with irrelevant but misleading information during the retention period (Harkin and Kessler, 2009, 2011). The present study differed from our previous research in the three crucial aspects. Firstly, we employed ecologically valid stimuli in form of electrical kitchen appliances on a kitchen countertop in order to address previous criticism of our research with letters in locations as these may not have tapped into the primary concerns of checkers. Secondly, we tested whether these ecological stimuli would allow us to employ a simpler (un-blocked) design while obtaining similarly robust results. Thirdly, in Experiment 2 we improved the measure of confidence as a metacognitive variable by using a quantitative scale (0–100), which indeed revealed more robust effects that were quantitatively related to accuracy of performance. The task in the present study was to memorize four appliances, including their states (on/off), and their locations on the kitchen countertop. Memory accuracy was tested for the states of appliances in Experiment 1, and for their locations in Experiment 2. Intermediate probes were identical in both experiments and were administered during retention on 66.7% of the trials with 50% resolvable and 50% irresolvable/misleading probes. Experiment 1 revealed the efficacy of the employed stimuli by revealing a general impairment of high- compared to low checkers, which confirmed the ecological validity of our stimuli. In Experiment 2 we observed the expected, more differentiated pattern: High checkers were not generally affected in their WM performance (i.e., no general capacity issue); instead they showed a particular impairment in the misleading distractor-probe condition. Also, high checkers’ confidence ratings were indicative of a general impairment in metacognitive functioning. We discuss how specific executive dysfunction and general metacognitive impairment may affect memory traces in the short- and in the long-term.

Effects of cognitive self-consciousness on visual memory in obsessive-compulsive disorder

Previous research has documented high trait cognitive self-consciousness (CSC) in obsessive-compulsive disorder (OCD). It remains unclear whether elevated CSC levels can also explain cognitive performance deficits that have frequently been found in OCD. This study examined whether experimentally heightened CSC affects visual memory performance in OCD. OCD participants and healthy controls completed a complex figure test under three experimental conditions: simultaneously focusing on their thoughts (= CSC condition), simultaneously focusing on acoustic stimuli (= dual-task condition), and without a parallel task (= standard condition). In the OCD sample both the CSC condition and the dual-task condition reduced memory performance compared to the standard condition, whereas in controls only the dual-task condition led to reduced performance. Results indicate that raising CSC in OCD has a deteriorating effect on memory encoding that parallels the effect of a secondary task. High CSC and its effects on cognitive performance might be amenable to meta-cognitive treatment approaches.

Managing complexity: impact of organization and processing style on nonverbal memory in autism spectrum disorders

The contributions of cognitive style and organization to processing and recalling a complex novel stimulus were examined by comparing the Rey Osterrieth Complex Figure (ROCF) test performance of children, adolescents, and adults with ASD to clinical controls (CC) and non-impaired controls (NC) using the Developmental Scoring System. The ROCF task involves a complex structure with strong organizational or integrative processing demands. The individuals with ASD relied on a predominantly part-oriented strategy to cope with the complexity of the task and did not make the typical developmental shift to a configurational approach. Both processing style and organization (whether pieces of information were perceived as connected to one another in a meaningful way) contributed to structural recall in the ASD group.

Influence of specific obsessive-compulsive symptom dimensions on strategic planning in patients with obsessive-compulsive disorder

OBJECTIVE: This study investigates obsessive-compulsive disorder patients in terms of strategic planning and its association with specific obsessive-compulsive symptom dimensions. METHOD: We evaluated 32 obsessive-compulsive disorder patients. Strategic planning was assessed by the Rey-Osterrieth Complex Figure Test, and the obsessive-compulsive dimensions were assessed by the Dimensional Yale-Brown Obsessive-Compulsive Scale. In the statistical analyses, the level of significance was set at 5%. We employed linear regression, including age, intelligence quotient, number of comorbidities, the Yale-Brown Obsessive-Compulsive Scale score, and the Dimensional Yale-Brown Obsessive-Compulsive Scale. RESULTS: The Dimensional Yale-Brown Obsessive-Compulsive Scale "worst-ever" score correlated significantly with the planning score on the copy portion of the Rey-Osterrieth Complex Figure Test (r = 0.4, p = 0.04) and was the only variable to show a significant association after linear regression (β = 0.55, t = 2.1, p = 0.04). Compulsive hoarding correlated positively with strategic planning (r = 0.44, p = 0.03). None of the remaining symptom dimensions presented any significant correlations with strategic planning. CONCLUSION: We found the severity of obsessive-compulsive symptoms to be associated with strategic planning. In addition, there was a significant positive association between the planning score on the copy portion of the Rey-Osterrieth Complex Figure Test copy score and the hoarding dimension score on the Dimensional Yale-Brown Obsessive-Compulsive Scale. Our results underscore the idea that obsessive-compulsive disorder is a heterogeneous disorder and suggest that the hoarding dimension has a specific neuropsychological profile. Therefore, it is important to assess the peculiarities of each obsessive-compulsive symptom dimension.

Remembering and forgetting: directed forgetting effect in obsessive-compulsive disorder

It has been reported that episodic memory seems to be impaired in patients with obsessive-compulsive disorder (OCD) because the patients repeat a specific checking behavior, but it is still unknown if OCD patients show memory impairments associated with their unique symptoms or not. To study episodic memory in OCD patients, we examined the directed forgetting effect. Patients with OCD and healthy control participants were given a list of 24 emotionally neutral everyday words (12 remember [R]-cued words and 12 forget [F]-cued words) under two conditions: List and Item. The results of our study showed that OCD patients recalled a number of F-cued words similar to that for controls and relatively fewer R-cued words than controls under both List and Item conditions. Consequently, the directed forgetting effect was smaller in OCD patients than controls. Our results demonstrated that both selective encoding and retrieval inhibition processes are impaired in OCD, and we suggest that recall of unfavorable items to be forgotten intruded into necessary items to be remembered. This impairment in episodic memory may partially account for some of the unique clinical symptoms of OCD.

Nonverbal memory and organizational dysfunctions are related with distinct symptom dimensions in obsessive-compulsive disorder

Recent acceptance that obsessive-compulsive disorder (OCD) represents a heterogeneous phenomenon has underscored the need for dimensional approaches to this disorder. However little is known about the relation between neuropsychological functions and symptom dimensions. The purpose of this study was to identify the cognitive deficits correlated with specific symptom dimensions. Thirteen categories in the Yale-Brown Obsessive Compulsive Scale symptom checklist from 144 patients with OCD were analyzed by principal component analysis. Correlations between identified symptom dimensions and neuropsychological functioning, measured by the Boston Qualitative Scoring System, were analyzed. Five factors or dimensions were identified: contamination/cleaning, hoarding, symmetry/ordering, obsessions/checking, and repeating/counting. Dysfunctions in nonverbal memory and organizational strategies were related to the symmetry/ordering dimension and the obsessions/checking dimension, respectively. The results of the present study support a transculturally stable symptom structure for OCD. They also suggest the possibility that nonverbal memory dysfunction and organizational impairment are mediated by distinct obsessive-compulsive dimensions.

Executive function profile of Chinese boys with attention-deficit hyperactivity disorder: different subtypes and comorbidity

This study examined the executive function (EF) profile of Chinese boys with attention-deficit hyperactivity disorder (ADHD) using a large sample. Executive function performance within the ADHD subtypes and the effects of comorbidity were also investigated. Five hundred Chinese boys (375 with ADHD and 125 controls) aged 6-15 completed a battery of EF tests. Boys with all types of ADHD performed worse in all of the EF tests than age- and intelligence quotient-matched healthy controls. The boys with the inattention ADHD subtype and the combined subtype showed similar impairments across different EF tasks, whereas the boys with the hyperactive-impulsive ADHD subtype primarily displayed deficits in theory of mind and visual memory. Comorbid oppositional defiant disorder/conduct disorder had no additional influence on the EF characteristics of the boys with ADHD only, whereas comorbid learning disorder increased the severity of inhibition and shifting impairments.

Memory and strategic processing in first-degree relatives of obsessive compulsive patients

BACKGROUND

The same executive dysfunctions and alterations in neuroimaging tests (both functional and structural) have been found in obsessive-compulsive patients and their first-degree relatives. These neurobiological findings are considered to be intermediate markers of the disease. The aim of our study was to assess verbal and non-verbal memory in unaffected first-degree relatives, in order to determine whether these neuropsychological functions constitute a new cognitive marker for obsessive-compulsive disorder (OCD).

METHOD

Recall and use of organizational strategies in verbal and non-verbal memory tasks were measured in 25 obsessive-compulsive patients, 25 unaffected first-degree relatives and 25 healthy volunteers.

RESULTS

First-degree relatives and healthy volunteers did not show differences on most measures of verbal memory. However, during the recall and processing of non-verbal information, deficits were found in first-degree relatives and patients compared with healthy volunteers.

CONCLUSIONS

The presence of the same deficits in the execution of non-verbal memory tasks in OCD patients and unaffected first-degree relatives suggests the influence of certain genetic and/or familial factors on this cognitive function in OCD and supports the hypothesis that deficits in non-verbal memory tasks could be considered as cognitive markers of the disorder.

Regional gray and white matter volume abnormalities in obsessive-compulsive disorder: a voxel-based morphometry study

Previous studies have demonstrated both functional and structural abnormalities in the frontal-striatal-thalamic circuits in obsessive-compulsive disorder (OCD). The purpose of this study was to assess volume abnormalities not only of gray matter (GM), but also of white matter (WM) in patients with OCD using voxel-based morphometry (VBM). Subjects consisted of 23 patients with OCD and 26 normal control subjects. All patients were drug-free for at least 2 weeks before the study. Three-dimensional T1-weighed MR images were obtained in all subjects. Optimized voxel-based morphometry was performed to detect structural difference between the two groups. The patients with OCD demonstrated a significant reduction of GM volume in the bilateral medial prefrontal cortex, right premotor area, right orbitofrontal cortex (OFC), right dorsolateral prefrontal cortex, and bilateral temporal and occipital regions. The OCD patients also showed a significant WM volume increase in the right anterior limb of the internal capsule, right orbitofrontal region, and a significant WM volume reduction in the left anterior cingulate gyrus. Our findings are consistent with previous studies implicating dysfunction of the frontal cortex including the OFC. The results suggested that WM volume abnormalities in the orbitofrontal region, anterior limb of the internal capsule, and anterior cingulate gyrus would imply abnormalities in the pathways of frontal-striatal circuits.

Set-shifting abilities, central coherence, and handedness in anorexia nervosa patients, their unaffected siblings and healthy controls: exploring putative endophenotypes

OBJECTIVE

There is consistent evidence that anorexia nervosa (AN) is associated with an impairment of set-shifting abilities and central coherence. No study to date investigated handedness in AN. Our aim was to study set-shifting abilities, central coherence, and handedness in subjects with lifetime AN, in a sample of unaffected sisters and in healthy controls, in order to explore their suitability as endophenotypes of AN.

METHODS

The Edinburgh Handedness Inventory and several neuropsychological tasks (Wisconsin Card Sorting Test, Trail Making Test, Rey-Osterrieth Complex Figure Test, Overlapping Figures Test, Object Assembly and Block Design) were administered to 153 subjects with lifetime AN, 28 unaffected sisters and 120 healthy controls.

RESULTS

AN subjects and their healthy sisters showed poorer performances on most tasks investigating set-shifting and central coherence. In addition, we did not find any differences between long-term recovered subjects, weight-restored AN patients and those in an acute phase of their illness. AN subjects were significantly more likely to be left-handed than healthy controls (OR=2.8, 95% C.I. 1.1-7.2).

CONCLUSIONS

Set-shifting and central coherence seem to be promising cognitive endophenotypes that might help in the understanding of the pathogenetic processes involved in AN. Further studies on larger samples are needed to explore the generalizability and implications of our findings concerning handedness.

Impairment of verbal learning and memory and executive function in unaffected siblings of probands with bipolar disorder

OBJECTIVES

Impairments in executive function and memory have been reported in relatives of patients with bipolar disorder, suggesting that they could be potential endophenotypes for genetic studies, but the findings are inconsistent. In this study, neuropsychological performance in unaffected siblings of probands with family loading for bipolar disorder is compared to that of individually matched healthy controls. We hypothesized that performance on tests of executive functions and memory would be impaired in unaffected siblings of probands with bipolar disorder compared to matched healthy controls.

METHODS

We evaluated 30 unaffected siblings of probands with bipolar I disorder and 30 individually matched healthy controls using tests of attention, executive function, and memory. Unaffected siblings and healthy control subjects did not differ with respect to gender, age, and years of education.

RESULTS

Unaffected siblings performed poorly on the Tower of London test (TOL), the Rey's auditory verbal learning test (RAVLT), and the Rey's complex figure test. In the multivariate analysis, significance was noted for the TOL, total number of moves (p = 0.007) and the RAVLT total learning score (p = 0.001).

CONCLUSIONS

Our study suggests that the deficits in verbal learning and memory and executive functions (planning) could be potential endophenotypes in bipolar disorder. These deficits are consistent with the proposed neurobiological model of bipolar disorder involving the frontotemporal and subcortical circuits. Future studies could couple cognitive and imaging strategies and genomics to identify neurocognitive endophenotypes in bipolar disorder.

Evidence for specific cognitive deficits in visual information processing in patients with OCD compared to patients with unipolar depression

OBJECTIVE

Neuropsychological studies comparing cognitive performance in patients suffering from Obsessive-Compulsive Disorder (OCD) or Major Depressive Disorder (MDD) revealed deficits in the domains of verbal fluency and viso-motor speed/set shifting in both groups. Spatial working memory deficits, however, have been identified as specific markers of OCD. As yet, it has not been substantiated whether deficits in visual organization and complex visual memory are also specific to OCD and are not shared by MDD.

METHOD

Test performance in seven cognitive domains was assessed in 40 OCD patients, 20 MDD patients, and 40 healthy controls. Patient groups were matched according to severity of depressive symptoms.

RESULTS

Deficits shared by both patient groups, as compared to controls, were found in delayed spatial recall and verbal fluency while verbal memory was normal in both patient groups. Only patients with OCD, but not MDD patients were impaired in the domains visual memory, viso-motor speed/set shifting, visual organization, and problem solving. In addition, OCD patients differed significantly from MDD subjects in visual organization and problem solving. Visual organization scores correlated significantly with severity of current compulsions in the OCD group (r=-.324).

CONCLUSIONS

OCD patients demonstrate difficulties in visual organization and mental manipulation of complex visual material, which are not accounted for by depressive symptoms and which constitute a specific cognitive deficit of the disorder.