Unique neuropsychological profiles in adhd subtype presentations

Learning and memory for verbal and visual information was compared in children and adolescents with Attention Deficit Hyperactivity Disorder (ADHD) of Combined Type and Predominantly Inattentive Type. Compared to a typically developing group, the ADHD groups were found to have unique difficulties. These findings add to the current research knowledge.

Neuropsychological changes following cognitive-behavioral treatment of obsessive-compulsive disorder (OCD)

Previous research has suggested that individuals with OCD show compromised performance on tests assessing visuospatial and executive processes. This study aimed to further examine such findings by investigating the relationship between OCD symptom improvement following cognitive-behavioral therapy and changes in neuropsychological performance in individuals with OCD (n = 26), compared to test-retest control participants (n = 10). Successful treatment of OCD led to improvements relative to the control group on neuropsychological tasks measuring spatial working memory. Neuroscientific models of OCD consider such findings to be consistent with possible cortical dysfunction in OCD. However, a significant limitation of the study is in its inability to discount alternative explanations for this finding, such as the influence of changes in beliefs. Implications are discussed.

The relationship between neuropsychological performance, cognitive confidence, and obsessive-compulsive phenomena : a pilot study

Drawing on neuropsychological and cognitive-behavioral approaches to Obsessive-Compulsive Disorder (OCD), the present study examined the association between memory performance, cognitive confidence, and OCD phenomena. Forty-six analogue participants completed a series of self-report questionnaires and neuropsychological tasks before and after a manipulation of confidence in memory It was found that cognitive confidence predicts OCD symptoms over and above the influence of depressive symptoms and other OCD-related beliefs. Participants reported higher levels of cognitive confidence following positive feedback on the manipulation task. However, changes in cognitive confidence following the manipulation task were not reflected in neuropsychological performance. Implications for theory and treatment are discussed.

A neuropsychological study of prefrontal lobe function in the positive and negative subtypes of schizophrenia.

The symptoms of schizophrenia are frequently divided into positive and negative subtypes. It has been suggested that the negative symptoms are similar to those seen with prefrontal lobe cortical dysfunction. Several neuropsychological investigations of that hypothesis have been carried out, but none have directly compared a negative symptom group with a positive symptom group on the same test battery. In the present study, the Positive and Negative Syndrome Scale (PANSS; Kay, Fiszbein, & Opler, 1987) was used to distinguish two groups of 20 patients with schizophrenia with predominant positive or negative symptoms. A battery of 7 neuropsychological tests considered capable of isolating prefrontal lobe dysfunction was administered. A significant group difference was noted on 6 of the tests; the negative symptom group performed much worse than the positive symptom group. The results of this study support the hypothesis that a relationship exists between the negative symptoms of schizophrenia and prefrontal lobe dysfunction.

Assessment of cognitive function in heart failure patients

Background
Research on the cognitive capacity of heart failure patients is limited, with a paucity of benchmark information available for this population. It is highly likely that cognitive deficits affect patients' understanding of disease and treatment requirements, as well as limiting their functional capacity and ability to implement treatment plans, and undertake self-care.

Aims
The purpose of this study was to establish a comprehensive neurocognitive profile of the heart failure patient through systematic neurocognitive assessment and to determine whether an association existed between severity of heart failure and cognitive abilities.

Methods
Thirty-eight patients were recruited from the heart failure patient databases of two metropolitan hospitals in Melbourne, Australia. Participants were individually assessed using four standardised, internationally recognised neuropsychological tests that examined current and premorbid intelligence, memory and executive functioning.

Results
Although there was no significant decline from premorbid general intellectual function, other specific areas of deficit, including impaired memory and executive functioning, were identified. There were no significant correlations between heart failure severity and the neurocognitive measures used.

Conclusion
The results support the need to recognise cognitive impairment in people with heart failure and to develop an abbreviated method of assessing cognitive function that can be easily implemented in the clinical setting. Identifying cognitive deficits in this population will be useful in guiding the content and nature of treatment plans to maximise adherence and minimise worsening of heart failure symptoms.

Omega 3 fatty acids and the brain : review of studies in depression

The brain is a lipid-rich organ containing mostly complex polar  phospholipids, sphingolipids, gangliosides and cholesterol. These lipids are involved in the structure and function of cell membranes in the brain. The glycerophospholipids in the brain contain a high proportion of  polyunsaturated fatty acids (PUFA) derived from the essential fatty acids, linoleic acid and alpha-linolenic acid. The main PUFA in the brain are docosahexaenoic acid (DHA, all cis 4,7,10,13,16,19-22:6) derived from the omega 3 fatty acid, alpha-linolenic acid, and arachidonic acid (AA, all cis 5,8,11,14-20:4) and docosatetraenoic acid (all cis 7,10,13,16-22:4), both derived from the omega 6 fatty acid, linoleic acid. Experimental studies in animals have shown that diets lacking omega 3 PUFA lead to substantial disturbances in neural function, which in most circumstances can be restored by the inclusion of omega 3 PUFA in the diet. In the past 10 years there has been an emerging interest in treating neuropsychological  disorders (depression and schizophrenia) with omega 3 PUFA. This paper discusses the clinical studies conducted in the area of depression and omega 3 PUFA and the possible mechanisms of action of these PUFA. It is clear from the literature that DHA is involved in a variety of processes in neural cells and that its role is far more complex than simply influencing cell membrane properties.

Abstracts of the Inaugural Australian Conference for Cognitive Neuropsychology and Cognitive Neuropsychiatry

The first Australian Conference for Cognitive Neuropsychology and Cognitive Neuropsychiatry was conducted by the School of Psychology at Deakin University, Geelong, from Friday, July 13 to Sunday, July 15 and was attended by over 50 cognitive psychologists, neuropsychologists and speech pathologists from Australia, New Zealand, Singapore and the UK. The Conference aimed to bring together researchers from different disciplines including linguistics, psychology, philosophy and speech pathology to present research that relates (neuropsychological or psychiatric) impairment to theories of normal cognitive functioning. The scientific program of the conference included 24 papers of exceptional quality. They were organised into the following thematic sessions: Disorders of language comprehension and production; Semantic memory and category-specific disorders; Reading: development and acquired dyslexia; Writing: development and acquired dyslexia; Memory; Object and face recognition; Theory of mind; Misidentification syndromes. Keynote speakers were Professor Andy Young from the University of York, England and Professor Max Coltheart from the Macquarie Centre for Cognitive Sciences, Sydney.

Sex differences in past tense overregularization

Hartshorne and Ullman (2006) presented naturalistic language data from 25 children (15 boys, 10 girls) and showed that girls produced more past tense overregularization errors than did boys. In particular, girls were more likely to overregularize irregular verbs whose stems share phonological similarities with regular verbs. It was argued that the result supported the Declarative/Procedural model of language, a neuropsychological analogue of the dual-route approach to language. In the current study we present experimental data that are inconsistent with these naturalistic data. Eighty children (40 males, 40 females) aged 5;0–6;9 completed a past tense elicitation task, a test of declarative memory, and a test of non-verbal intelligence. The results revealed no sex differences on any of the measures. Instead, the best predictors of overregularization rates were item-level features of the test verbs. We discuss the results within the context of dual versus single route debate on past tense acquisition.

Integrity of the circadian time-keeping system in chronic fatigue syndrome

Chronic Fatigue Syndrome (CFS) is a debilitating condition in which severe, ongoing fatigue is the most prominent of a complex of somatic, psychological and neuropsychological symptoms. The aetiology of CFS remains uncertain and, to date, efforts to distinguish a clear pathophysiological profile for the disorder have been unsuccessful. Current evidence suggests that, rather than being a discrete disease entity with a single cause, CFS is a clinical condition resulting from the interaction of a number of pathophysiological factors, including acute infections, stress and psychiatric disorder. Recently, there has been some interest in the proposition that disordered circadian time-keeping may contribute to the development and/or course of the illness. The rationale for the investigation of circadian factors in CFS is based on the fact that disorders known to be associated with circadian dysregulation, such as jet lag and shiftwork related syndromes have a high degree of symptomatological overlap with CFS. Also, the presence of circadian disturbance could account, in part, for other phenomenological aspects of CFS, including the high rates of comorbid affective disturbance, and the reports of low-level immune dyregulation among sufferers. While several recent studies have produced some evidence of chronobiological dysregulation in CFS patients, much work remains before conclusions can be drawn about the presence, nature and clinical significance of circadian disturbance in CFS. This thesis describes a series of studies that were designed to systematically investigate: 1. whether CFS is associated with a state of circadian dysregulation, and 2. whether circadian dysregulation contributes significantly to the symptomatology of CFS. The first of the 5 studies reported here compared the circadian patterns of sleep-activity of CFS sufferers with those of healthy controls. Results indicated that CFS patients' sleep-activity cycles were significantly phase delayed compared to controls, and that some aspects of their circadian profiles of sleep-activity were related to some measures of sleep-disturbance and well-being. Studies 2 and 3 investigated the relationship between rhythms of sleep-wake and core temperature in CFS patients and healthy controls. The major finding from these studies was that sleep-wake and core temperature rhythms appear to be less effectively synchronised. Further evidence was collected that suggested that there was a relationship between circadian parameters and symptom measures in the CFS group. While this indicated that circadian dysregulation is linked in some way to the symptoms of CFS, assessment of the actual clinical significance of circadian disturbances required the use of a prospective methodology. The final two studies, therefore, report on a placebo-controlled trial of clinical interventions that were designed to restore circadian integrity to CFS patients, in order to see whether this would lead to a reduction in symptom number or severity. Results indicated that, although patients experienced improvements across a range of measures of symptoms and functional capacity, these were small in magnitude, of unlikely clinical significance, and no greater, in general, to improvements reported by patients who underwent placebo treatment. These results, along with those of the earlier studies, are discussed with respect to their implications regarding the presence and significance of circadian dysregulation. It is concluded that, while they provide evidence that CFS is associated with a degree of both internal and external circadian desynchrony, these findings suggest that circadian dysregulation is likely to be only a peripheral, contributor to the processes that generate and maintain the symptom complex. These findings are discussed with respect to how they contribute to our overall understanding of this multi-dimensional condition, and the implications they have for the continuing effort to investigate the causes and treatment of CFS.

An integrated theory of sexual offending

This paper represents a first attempt to provide an integrated framework to explain the onset, development, and maintenance of sexual offending. According to the Integrated Theory of Sexual Offending (ITSO), sexual abuse occurs as a consequence of a number of interacting causal variables. We examine the factors that affect brain development (evolution, genetic variations and neurobiology) and ecological factors (social and cultural environment, personal circumstances, physical environment) and discuss how they impact upon core neuropsychological functions underpinning human action. The ITSO then explains how clinical symptoms arise from the interaction between these neurological systems and ecological factors. The capacity of the ITSO to incorporate competing theories of sexual offending is considered, and we end the paper by critically evaluating its usefulness in stimulating research and further theory development.

Increased positive thought disorder with illness duration in patients with schizophrenia

It is unclear whether the severity of positive formal thought disorder, a core clinical feature of schizophrenia, is stable or worsening through the chronic course of the illness. The neurocognitive basis for positive thought disorder also remains unclear. The aim of the present paper was to examine the relationship between thought disorder as measured by the Thought Disorder Index (TDI) and duration of illness and neuropsychological indices in 79 patients with schizophrenia. TDI scores increased in proportion to illness duration. TDI scores were not associated with verbal memory or executive functioning. These results indicate an ongoing worsening of positive thought disorder through the course of illness in schizophrenia.