Cognitive functioning in depersonalization disorder

Depersonalization disorder (DPD) is a dissociative disorder characterized by a subjective sense of unreality and detachment, and has been associated with deficits in perception and short-term memory. In this study, 21 DPD and 17 healthy comparison participants free of psychiatric disorders were administered a comprehensive neuropsychologic battery. The groups did not differ in full-scale, verbal, and performance IQ (Wechsler Adult Intelligence Scale), in working memory (Paced Auditory Serial Addition Test), or in selective attention (Digit Span with Distracters). The DPD group performed significantly worse on immediate visual and verbal recall (Wechsler Memory Scale, Revised), but not on delayed recall. Dissociation severity was significantly correlated with processing slowness and distractibility. We conclude that DPD is associated with cognitive disruptions in early perceptual and attentional processes.     

A neuropsychological investigation of prefrontal cortex involvement in acute mania

OBJECTIVE: Mania has received little attention from a contemporary neuropsychological perspective despite its clear resemblance to the disinhibition syndrome sometimes seen after frontal brain injury, particularly injury to the inferior aspect of the prefrontal cortex. The purpose of this investigation was to describe the neuropsychological profile of severe acute mania by using a range of tasks selected primarily for the detection of localized neural disruption within the prefrontal cortex. METHOD: Fifteen acutely manic inpatients were compared with 30 nonpsychiatric subjects on tasks from the Cambridge Automated Neuropsychological Test Battery (Tower of London, spatial working memory, intradimensional-extradimensional attentional shift, and rapid visual information processing tasks) and on the Iowa Gambling Task, Stroop Color and Word Test, a verbal fluency task, and the California Verbal Learning Test. RESULTS: Discriminant function analysis identified deficits in sustained attention (on the rapid visual information processing task) and verbal learning (on the California Verbal Learning Test) as the best indicators of manic performance, rather than deficits on any of the tests of executive functioning. The model correctly classified 91% of subjects overall and 87% of manic subjects. Manic patients did not resemble patients with ventromedial prefrontal cortex damage in their performance on the Iowa Gambling Task. CONCLUSIONS: Acute mania is characterized by core deficits in verbal memory and sustained attention against a background of milder impairments in functions that are traditional measures of prefrontal cortex integrity (attentional set shifting, planning, working memory). The data do not implicate ventral prefrontal cortex disruption as a locus of pathology in acute mania. Verbal memory and sustained attention deficits may relate differentially to the state and trait characteristics of bipolar disorder.     

Attention Deficits in Patients with Persisting Postconcussive Complaints: A General Deficit or Specific Component Deficit?

This study aimed to examine attentional performance in patients with persisting postconcussive complaints, using a multi-componential perspective. Comparisons of attentional performances of 92 patients with postconcussive complaints and 86 normal controls were conducted using tests of sustained attention (Sustained Attention to Response Task; Digit Backward Span), selective attention (Stroop Word-Color Test; Color Trails Test), divided attention (Paced Auditory Serial Addition Test; Symbol Digit Modalities Test), and attentional control processing (Six Elements Test; Tower of Hanoi). Questionnaires on daily life inattentive behaviour were also administered to all participants and their significant others. A MANOVA indicated that patients with persisting postconcussive complaints demonstrated a general deficit in attentional performance as compared with their normal controls, F (18, 145) = 7.939, p = .005. These patterns still persisted when measures of emotional disturbance were controlled, F (18, 143) = 5.159, p = .005. Moreover, for sustained attention and selective attention, we were able to statistically control for speed and the differences remained. Future research should be conducted to better control the potential confound of speed for all the attentional components in order to differentiate any specific component deficits in these patients.     

Changes in cognitive functioning following comprehensive treatment for first episode patients with schizophrenia spectrum disorders

The course of cognitive functioning over a 1-year period was examined among a community cohort of individuals presenting with first episode schizophrenia spectrum psychosis. Data were obtained for 83 outpatients at entry to an early intervention program and 12 months later on the National Adult Reading Test, Wechsler Adult Intelligence Scales-Third Edition, Wechsler Memory Scales-Third Edition, Paced Auditory Serial Addition Task, Wisconsin Card Sorting Test, Stroop Colour and Word Test, Trail Making Test, Continuous Performance Task and Thurstone Word Fluency Test. Paired sample t-tests indicated significant and positive changes in verbal and non-verbal intelligence, auditory and visual memory, working memory and some aspects of executive functioning. Processing speed also improved though remained an area of relative weakness for this sample. Findings indicated generally average performance at both assessment periods. Neither gender nor duration of untreated psychosis were related to the degree of change in cognitive functioning for this sample. The implications of these findings and the impact of early intervention with this population are discussed.     

Attentional deficits in patients with persisting postconcussive complaints: a general deficit or specific component deficit?

This study aimed to examine attentional performance in patients with persisting postconcussive complaints, using a multi-componential perspective. Comparisons of attentional performances of 92 patients with postconcussive complaints and 86 normal controls were conducted using tests of sustained attention (Sustained Attention to Response Task; Digit Backward Span), selective attention (Stroop Word-Color Test; Color Trails Test), divided attention (Paced Auditory Serial Addition Test; Symbol Digit Modalities Test), and attentional control processing (Six Elements Test; Tower of Hanoi). Questionnaires on daily life inattentive behaviour were also administered to all participants and their significant others. A MANOVA indicated that patients with persisting postconcussive complaints demonstrated a general deficit in attentional performance as compared with their normal controls, F(18, 145) = 7.939, p = .005. These patterns still persisted when measures of emotional disturbance were controlled, F(18, 143) = 5.159, p = .005. Moreover, for sustained attention and selective attention, we were able to statistically control for speed and the differences remained. Future research should be conducted to better control the potential confound of speed for all the attentional components in order to differentiate any specific component deficits in these patients.     

Neuropsychological performance in schizotypal personality disorder: importance of working memory

BACKGROUND: Cognitive deficits consistently have been reported in schizophrenia patients and in patients with schizotypal personality disorder. For this study, the authors wanted to identify which of the domains of cognitive impairment represent "core" deficits of schizophrenia, comparing subjects with schizotypal personality disorder to two comparison groups: healthy volunteers and patients with personality disorders unrelated to schizophrenia. METHOD: Three groups completed a neuropsychological battery: patients with DSM-III-R schizotypal personality disorder (N=82); patients with DSM-III-R personality disorders unrelated to schizophrenia (i.e., a personality disorder other than schizotypal, schizoid, or paranoid [N=44]); and healthy volunteers (N=63). The battery included the California Verbal Learning Test, Trailmaking Test parts A and B, the Dot test of working memory, the Stroop Color and Word Test, the Paced Auditory Serial Addition Test, the WMS visual reproduction test, and the WAIS-R vocabulary and block design. RESULTS: Normative standards for performance that controlled for age, gender, and education were created from the scores of the healthy volunteers. Overall, schizotypal personality disorder patients performed significantly worse than the healthy volunteers and those with personality disorders unrelated to schizophrenia. Specifically, patients with schizotypal personality disorder demonstrated impaired performance on the Paced Auditory Serial Addition Test, WMS visual reproduction test, Dot test, and California Verbal Learning Test. In addition, in a regression analysis, performance on the Paced Auditory Serial Addition Test demonstrated the largest effect size. Indeed, it accounted for unique variance above and beyond all other cognitive measures, since controlling for Paced Auditory Serial Addition Test performance abolished group differences across all other measures. CONCLUSIONS: Patients with schizotypal personality disorder demonstrated moderate cognitive impairment compared with healthy volunteers (significant for seven out of 11 measures). These differences reached statistical significance for tasks of working memory, episodic memory, and delayed recall. Working memory performance accounted for the group differences. This study supports the view that working memory represents a core deficit of schizophrenia spectrum disorders.     

Cognitive impairment and optic nerve axonal loss in patients with clinically isolated syndrome

Objective

To investigate cognitive impairment, to assess optical nerve axonal loss, and to determinate whether there is correlation between optical nerve axonal loss and cognition impairment in Clinically Isolated Syndrome (CIS).

Methods

Fifteen CIS patients and 15 controls were submitted to Wechsler memory scale, Rey Auditory Verbal Learning, Rey Complex Figure, Paced Auditory Serial Addition, Digit Span, verbal fluency, stroop color, D2, and Digit Symbol tests. CIS patients were evaluated by optical coherence tomography (OCT) (23 eyes).

Results

CIS patients had worse performance in Paced Auditory Serial Addition Test (PASAT) 2 seconds (P = 0.009) and fluency tests (P = 0.0038). Optical nerve axonal loss was found more frequently in eyes with previous optic neuritis (ON) (85.7%) than in those without previous ON (21.7%) (P = 0.0146). There were no significant correlations between optical nerve axonal loss and cognitive findings.

Conclusions

CIS patients had worse cognitive performance than controls. OCT can detect axonal loss resulting from optical neuritis and subclinical axonal loss in eyes without previous optical neuritis. Optical nerve axonal loss was not correlated with cognition.     

Task-specific facilitation of cognition by cathodal transcranial direct current stimulation of the cerebellum

A role for the cerebellum in cognition is controversial, but it is a view that is becoming increasingly popular. The aim of the current study was to investigate this issue using transcranial Direct Current Stimulation (tDCS) during two cognitive tasks that require comparable motor skills, but different levels of working memory and attention. Three groups of twenty-two participants each performed the Paced Auditory Serial Addition Task (PASAT) and a novel variant of this task called the Paced Auditory Serial Subtraction Task (PASST), together with a verb generation task and its two controls, before and after the modulation of cortico-cerebellar connectivity using anodal or cathodal tDCS over the cerebellum. Participants' performance in the difficult PASST task significantly improved after cathodal stimulation compared to sham or anodal stimulation. Improvement in the easier PASAT was equal across all three stimulation conditions. Improvement in verbal response latencies were also greatest during the PASST task after cathodal stimulation, compared to sham and anodal stimulation, and became less variable. Results for the verb generation task complimented those for the PASST, such that the rate and consistency of participants' verbal responses were facilitated by cathodal stimulation, compared to sham and anodal stimulation. These findings suggest that DC stimulation over the right cerebellum affects working memory and attention differently depending on task difficulty. They support a role for the cerebellum in cognitive aspects of behaviour, whereby activity in the prefrontal cortex is likely dis-inhibited by cathodal tDCS stimulation over the right cerebellar cortex, which normally exerts an overall inhibitory tone on the cerebral cortex. We speculate that the cerebellum is capable of releasing cognitive resources by dis-inhibition of prefrontal regions of cerebral cortex, enhancing performance when tasks become demanding.     

Course of attention and memory after common whiplash: a two-years prospective study with age, education and gender pair-matched patients

Attentional functioning and memory of common whiplash patients were evaluated during the first two years after experiencing injury. The study was based on a non-selected sample of 117 whiplash patients referred from primary care and recruited according to a strict injury definition. All patients had a similar socioeconomic background, all being injured in automobile accidents and fully covered by insurance plans. Two years following initial trauma, 21 patients remained symptomatic. For each of these 21 patients, a counterpart matched by age, educational attainment and gender was selected from the group of patients who had fully recovered during the follow-up period. Symptomatic patients and matched controls were compared with regard to baseline, six-months and two-years findings. Examinations included testing of different aspects of attention (i.e. Digit Span, Corsi Block-Tapping Test, Trail Making Test, Number Connection Test, Paced Auditory Serial Addition Task) and memory functioning (California Verbal Learning Test). Cognitive functioning was assessed in conjunction with self-ratings of cognitive abilities (Cognitive Failures Questionnaire), well-being (Well-being Scale), headache and neckpain intensity, utilized medication and subjective complaints. Results show no impairment of memory in symptomatic patients. In attentional functioning, different levels of improvement were found for symptomatic patients and matched counterparts, with the former showing difficulty at follow-up with tasks of divided attention. Utilized medication and pain intensity could not explain this difference in recovery of attentional functioning between the groups. These findings suggest problems in selective aspects of attentional functioning after common whiplash, which under real life circumstances may explain these patients' cognitive complaints and cause adaptational problems in daily life.     

Neuropsychological performance in childhood OCD: A preliminary study

Background: Neuropsychological deficits have often been found in studies of adults with obsessive compulsive disorder (OCD). However, few studies have examined such impairment in children with OCD and of those studies published, the results are mixed. Methods: In the present study, 14 OCD children were compared to 24 healthy developing children of similar age and intellectual ability on a series of neuropsychological tests that assess response inhibition, abstract reasoning and problem solving, planning ability, verbal and nonverbal fluency, working memory, attention and information processing speed, and visual and verbal memory and learning. Results: No significant differences emerged between the children with OCD and healthy controls for working memory, verbal fluency, attention, information processing speed, concept formation/abstraction, and response inhibition. We observed some deficits and a trend toward performance differences between the groups for psychomotor speed and attention, cognitive flexibility, nonverbal fluency, planning ability, and verbal memory and learning. Results are partially consistent with those found in adults with OCD. Findings were not related to depressive symptoms or self‐report feeling of anxiety. Conclusions: This preliminary survey indicates that OCD children may have deficits for cognitive flexibility and planning ability and differ from adults with OCD in not presenting with poor response inhibition or memory deficits. Larger, multi‐site studies are warranted to help delineate the neurocognitive deficits associated with childhood OCD. Depression and Anxiety, 2010. © 2009 Wiley‐Liss, Inc.     

精神分裂症首次发病患者及其健康同胞认知功能的比较研究

目的 比较精神分裂症首次发病患者与健康同胞及正常对照认知功能的差异,探讨精神分裂症在认知功能领域的内表型.方法 采用目前常用的范畴流畅测验(CFT)、数字符号编码测验(DSCT)、连线测验(TMT)、韦克斯勒记忆量表第3版(WMS-Ⅲ)空间广度测验(WMS-ⅢSST)、霍普金斯词汇学习测验-修订版(HVLT-R)、简易视觉空间记忆测验-修订版(BVMT-R)、定步调听觉连续加法测验(PASAT)和威斯康星卡片分类测验-64(WCST-64)对92例精神分裂症首次发病患者(患者组)、56例健康同胞(同胞组)和62名健康对照者(对照组)的认知功能进行检测.结果 (1)患者组所有神经心理测验成绩均差于对照组,差异有统计学意义(P＜0.01).(2)同胞组的CFT、DSCT、TMT、HVLT-R即刻记忆和延迟记忆、BVMT-R即刻记忆、PASAT、WCST-64持续错误数、持续反应数和完成分类数的测验成绩差于对照组,差异有统计学意义(P＜0.05).(3)患者组与同胞组的CFT、WCST-64中的持续错误数、持续反应数和完成分类数测验成绩分别为(18.40±12.12)分比( 18.86±5.19)分、(16.48±8.19)分比(14.80±5.86)分、(18.76±10.91)分比(16.86 ±7.73)分、(1.33±2.81)分比(1.63±1.36)分,2组比较差异无统计学意义(P＞0.05),其他神经心理测验成绩比较,患者组差于同胞组,差异有统计学意义(P＜0.05).结论 精神分裂症首次发病患者存在处理速度、工作记忆、言语记忆、空间记忆、注意警觉和执行功能广泛性的认知功能损害,精神分裂症健康同胞存在处理速度、言语记忆、视觉记忆、注意警觉、执行功能的认知缺陷;语义流畅性功能和执行功能可能是精神分裂症的潜在内表型.     

Neuropsychological function in female victims of intimate partner violence with and without posttraumatic stress disorder.

BACKGROUND: Various aspects of neuropsychologic function have been reported to be abnormal in patients with posttraumatic stress disorder (PTSD); however, the majority of these data come from studies of seriously ill, treatment-seeking samples with substantial substance use comorbidity. Few studies have included similarly trauma-exposed subjects without PTSD, and fewer still have focused on women. METHODS: Thirty-nine female victims of intimate partner violence (IPV; 22 without lifetime PTSD and 17 with current PTSD), and 22 nonvictimized comparison (NC) subjects were administered tests of attention, working memory, visuoconstruction, language ability, learning and memory, and executive functioning. RESULTS: The IPV and NC subjects did not demonstrate statistically significant differences on most neuropsychologic tests, with the exception of those in the realm of working memory, visuoconstruction, and executive functioning. The IPV subjects, regardless of PTSD status, had poorer performance on tasks of speeded, sustained auditory attention and working memory (Paced Auditory Serial Addition Test) and response inhibition (Stroop). The IPV subjects with PTSD performed worse than NCs on a set-shifting task (Trail Making Test, Part B). No consistent relationships were noted between neuropsychologic functioning and severity of childhood abuse or domestic violence experiences. CONCLUSIONS: Cognitive deficits in IPV subjects were confined to measures of working memory, visuoconstruction, and executive function; were subtle; and were not uniformly worse among those with current PTSD. This pattern, however, is consistent with frontal-subcortical dysfunction in traumatized women. The clinical significance of these findings deserves further study.     

Executive control and learning pattern on the CVLT

We evaluated a 23 year-old man after recovery from encephalitis. In contrast to the expected pattern of increasingly better acquisition across the 5 learning trials of the California Verbal Learning Test (CVLT-2), he produced a "J-shaped" curve (Trials 1-5: 8,6,6,9,11). Because he also demonstrated excessive levels of proactive interference as well as poor divided attention, we hypothesized that his atypical learning pattern was due to a build-up of proactive interference secondary to executive dyscontrol. Using a large sample of 4462 healthy adult men, we identified four groups exhibiting various learning patterns. We found that a learning pattern similar to this patient (i.e., a drop after trial 1 followed by recovery) was rare (1.1% of the sample). Individuals with this learning pattern demonstrated increased perseverative responses, as well as greater difficulty maintaining cognitive set on the Wisconsin Card Sorting Test, decreased attentional control on the Paced Auditory Serial Addition Test, and greater levels of proactive interference on the CVLT. Taken together, the results of the study suggest that an early drop, followed by a recovery in learning trial performance, is associated with executive dyscontrol.     

Effects of Attention Process Training on cognitive functioning of schizophrenic patients

The goal of this study was to investigate the impact of Attention Process Training (APT) on cognitive functioning in schizophrenia. Twenty-four patients with schizophrenia were randomly assigned to one of the two following conditions: training by means of APT or no training. The dependent variables included measures of attention, memory and executive functions derived from a cancellation task, dichotic listening, dual task, Trail Making Test, Paced Auditory Serial Addition Task, Everyday Attention Questionnaire, Spain-Complutense Verbal Learning Test and Wisconsin Card Sorting Test (WCST). All participants were also rated on measures of positive and negative symptoms. The tasks were administrated to all participants at baseline. Participants in the training group received individual intensive APT twice a week, whereas the control group did not receive training. All participants were subsequently retested on the same tests. Although, contrary to expectations, neither group improved on clinical and information-processing measures of attention and memory, patients in the trained group had a significantly higher performance on executive function (as measured by the WCST) than did the control group. We conclude that it is feasible to use practice in attention to remediate executive function deficits in schizophrenia.     

On the nature of memory disturbance in multiple sclerosis

Thirty-seven patients with multiple sclerosis (MS) were compared to 26 normal controls of equivalent age, education, and verbal intelligence on measures of verbal learning and memory (Digit Span and Supraspan, Brown-Peterson Distractor Task, Selective Reminding Test, Story Recall, and Free Verbal Recall) and verbal fluency (Letter and Animal Fluency). The MS patients exhibited deficits on measures of secondary (long-term) memory and verbal fluency, but performed normally on measures of primary (short-term) memory, recognition memory, and rate of forgetting from secondary memory. These results suggest that the memory disturbance in MS results primarily from an imparied ability to access information from secondary memory, while encoding and storage capacity is intact. Degree of memory impairment was unrelated to length of illness, severity of disability, or self-reported depression.     

Memory, attention, and executive function in chronic fatigue syndrome.

OBJECTIVES--To examine cognitive function in chronic fatigue syndrome. METHODS--Twenty patients with chronic fatigue syndrome recruited from primary care and 20 matched normal controls were given CANTAB computerised tests of visuospatial memory, attention, and executive function, and verbal tests of letter and category fluency and word association learning. RESULTS: Patients with chronic fatigue syndrome were impaired, predominantly in the domain of memory but their pattern of performance was unlike that of patients with amnesic syndrome or dementia. They were normal on tests of spatial pattern recognition memory, simultaneous and delayed matching to sample, and pattern-location association learning. They were impaired on tests of spatial span, spatial working memory, and a selective reminding condition of the pattern-location association learning test. An executive test of planning was normal. In an attentional test, eight subjects with chronic fatigue syndrome were unable to learn a response set; the remainder exhibited no impairment in the executive set shifting phase of the test. Patients with chronic fatigue syndrome were also impaired on verbal tests of unrelated word association learning and letter fluency. CONCLUSION--Patients with chronic fatigue syndrome have reduced attentional capacity resulting in impaired performance on effortful tasks requiring planned or self ordered generation of responses from memory.     

Bipolar I patients with and without a history of psychotic symptoms: Do they differ in their cognitive functioning?

Recently, many reports have consistently demonstrated cognitive deficits in patients with bipolar disorder (BD), but their relationship with symptomatology, specifically psychotic symptoms, remains unclear. Our main hypothesis was that a history of hallucinations and/or delusions in the course of BD-I is associated with severe cognitive deficits. We investigated several cognitive functions (memory, attention, verbal fluency and executive functions) in 18 BD-I patients with a history of psychotic symptoms (HPS+), 17 BD-I patients without a history of psychotic symptoms (HPS-), 33 schizophrenic patients and 26 healthy control subjects. Both groups of BD-I patients were more impaired than the normal controls in attention, verbal memory, verbal fluency and executive functions. Only HPS+ BD-I patients showed more difficulties in completing the Stroop test than nonpsychotic bipolar patients. Nevertheless, after adjustment for the effects of current psychopathology, this difference disappeared. Schizophrenic subjects showed worse performance than BD-I subjects in verbal memory and verbal fluency. These results suggest that a history of psychotic symptoms in bipolar I disorder may not be associated with more cognitive deficits. Further research on euthymic bipolar patients with and without HPS is required to confirm these findings.     

On the nature of memory disturbance in multiple sclerosis

Abstract

Thirty-seven patients with multiple sclerosis (MS) were compared to 26 normal controls of equivalent age, education, and verbal intelligence on measures of verbal learning and memory (Digit Span and Supraspan, Brown-Peterson Distractor Task, Selective Reminding Test, Story Recall, and Free Verbal Recall) and verbal fluency (Letter and Animal Fluency). The MS patients exhibited deficits on measures of secondary (long-term) memory and verbal fluency, but performed normally on measures of primary (short-term) memory, recognition memory, and rate of forgetting from secondary memory. These results suggest that the memory disturbance in MS results primarily from an impaired ability to access information from secondary memory, while encoding and storage capacity is intact. Degree of memory impairment was unrelated to length of illness, severity of disability, or self-reported depression.     

Memory and information processing capacity after closed head injury.

The relation between duration of post-traumatic amnesia (PTA), performance on memory tests, and the Paced Auditory Serial Addition Task (PASAT) was examined in two samples of young adult closed head injury patients. Three different effects were isolated: (1) an attention and concentration factor, related to PASAT scores, (2) a deficit in the ability to place material into long-term memory storage, related to PTA durations, and (3) an impairment in the ability to retrieve material once it has been stored, which was not predicted by either PTA or PASAT.     

Verbal recall and recognition abilities in patients with Wilson's disease

Tests of memory and verbal fluency were administered to 19 neurologically impaired Wilson's patients, 12 non-neurologically impaired Wilson's patients and 15 normal control subjects. Wilson's patients with neurologic disease recalled significantly fewer words on the delayed recall version of the Rey Auditory Verbal Learning Test than control subjects (p less than .05) but they showed no impairment on the recognition version of this test. On a verbal fluency test (FAS) requiring the subject to retrieve items from different categories, Wilson's patients with neurologic disease generated significantly fewer words than control subjects (p less than .01). Results suggest that retrieval memory is mildly impaired in the neurologic WD group but rate of learning and rate of forgetting is normal.