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Neuropsychological Studies (neuropsychological + studies)
Selected AbstractsMemory in the aging brain: Doubly dissociating the contribution of the hippocampus and entorhinal cortexHIPPOCAMPUS, Issue 11 2007Andrew P. Yonelinas Abstract Since the time of Aristotle it has been thought that memories can be divided into two basic types; conscious recollections and familiarity-based judgments. Neuropsychological studies have provided indirect support for this distinction by suggesting that different regions within the human medial temporal lobe (MTL) are involved in these two forms of memory, but none of these studies have demonstrated that these brain regions can be fully dissociated. In a group of nondemented elderly subjects, we found that performance on recall and recognition tests was predicted preferentially by hippocampal and entorhinal volumes, respectively. Structural equation modeling revealed a double dissociation, whereby age-related reductions in hippocampal volume resulted in decreases in recollection, but not familiarity, whereas entorhinal volume was preferentially related to familiarity. The results demonstrate that the forms of episodic memory supported by the human hippocampus and entorhinal cortex can be fully dissociated, and indicate that recollection and familiarity reflect neuroanatomically distinct memory processes. © 2007 Wiley-Liss, Inc. [source] Neuropsychological studies in anorexia nervosaINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue S1 2005Kate Tchanturia PhD Abstract Neuropsychological findings in eating disorders are somewhat inconsistent. This may be because individual studies have used a broad range of tests on relatively small, heterogeneous clinical groups, thus limiting the detection of subtle neuropsychological differences in these patients. Therefore, rather than using broad assessments of a variety of neuropsychological functions, adoption of a more focused, hypothesis-driven approach based on clinical practice is proposed. This will allow more in-depth investigations of targeted functions and will improve the chances of detecting a problem, of exploring its ecologic validity, and of tailoring a treatment. We have demonstrated this approach using our neuropsychological studies of cognitive flexibility in anorexia nervosa (AN). © 2005 by Wiley Periodicals, Inc. [source] The cognitive phenotype in Klinefelter syndrome: A review of the literature including genetic and hormonal factorsDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 4 2009Richard Boada Abstract Klinefelter syndrome (KS) or 47,XXY occurs in ,1 in 650 males. Individuals with KS often present with physical characteristics including tall stature, hypogonadism, and fertility problems. In addition to medical findings, the presence of the extra X chromosome can lead to characteristic cognitive and language deficits of varying severity. While a small, but significant downward shift in mean overall IQ has been reported, the general cognitive abilities of patients with KS are not typically in the intellectual disability range. Most studies support that males with KS have an increased risk of language disorders and reading disabilities. Results of other studies investigating the relationship between verbal and nonverbal/spatial cognitive abilities have been mixed, with differing results based on the age and ascertainment method of the cohort studied. Executive function deficits have been identified in children and adults with KS, however, the research in this area is limited and further investigation of the neuropsychological profile is needed. In this article, we review the strengths and weaknesses of previous cognitive and neuropsychological studies in males with KS in childhood and adulthood, provide historical perspective of these studies, and review what is known about how hormonal and genetic factors influence cognitive features in 47,XXY/KS. © 2009 Wiley-Liss, Inc. Dev Disabil Res Rev 2009;15:284,294. [source] Neuropsychological studies in anorexia nervosaINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue S1 2005Kate Tchanturia PhD Abstract Neuropsychological findings in eating disorders are somewhat inconsistent. This may be because individual studies have used a broad range of tests on relatively small, heterogeneous clinical groups, thus limiting the detection of subtle neuropsychological differences in these patients. Therefore, rather than using broad assessments of a variety of neuropsychological functions, adoption of a more focused, hypothesis-driven approach based on clinical practice is proposed. This will allow more in-depth investigations of targeted functions and will improve the chances of detecting a problem, of exploring its ecologic validity, and of tailoring a treatment. We have demonstrated this approach using our neuropsychological studies of cognitive flexibility in anorexia nervosa (AN). © 2005 by Wiley Periodicals, Inc. [source] Cognitive profile in a large french cohort of adults with Prader,Willi syndrome: differences between genotypesJOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 3 2010P. Copet Abstract Background Prader,Willi syndrome (PWS) is a rare genetic disorder characterised by developmental abnormalities leading to somatic and psychological symptoms. These include dysmorphic features, impaired growth and sexual maturation, hyperphagia, intellectual delay, learning disabilities and maladaptive behaviours. PWS is caused by a lack of expression of maternally imprinted genes situated in the 15q11-13 chromosome region. The origin is a ,de novo' deletion in the paternal chromosome in 70% of the cases and a maternal uniparental disomy in 25%. The two main genotypes show differences, notably regarding cognitive and behavioural features, but the mechanisms are not clear. This study assessed cognitive impairment in a cohort of adults with genetically confirmed PWS, analysed their profiles of cognitive strengths and weaknesses, and compared the profiles in terms of genotype. Methods Ninety-nine male and female adults participated, all inpatients on a specialised unit for the multidisciplinary care of PWS. The Wechsler Adult Intelligence Scale (WAIS-III) was administered to all patients in identical conditions by the same psychologist. Eighty-five patients were able to cope with the test situation. Their scores were analysed with non-parametric statistical tools. The correlations with sex, age and body mass index were explored. Two genotype groups were compared: deletion (n = 57) and non-deletion (n = 27). Results The distribution of intelligence quotients in the total cohort was non-normal, with the following values (medians): Full Scale Intelligence Quotient (FSIQ): 52.0 (Q1:46.0; Q3:60.0), Verbal Intellectual Quotient (VIQ): 53.0 (Q1:48; Q3:62) and Performance Intellectual Quotient (PIQ): 52.5 (Q1:48; Q3:61). No correlation was found with sex, age or body mass index. Comparison between groups showed no significant difference in FSIQ or VIQ. PIQ scores were significantly better in the deletion group. The total cohort and the deletion group showed the VIQ = PIQ profile, whereas VIQ > PIQ was observed in the non-deletion group. The subtest scores in the two groups showed significant differences, with the deletion group scoring better in three subtests: object assembly, picture arrangement and digit symbol coding. Some relative strengths and weaknesses concerned the total cohort, but others concerned only one genotype. Discussion We documented a global impairment in the intellectual abilities of a large sample of French PWS patients. The scores were slightly lower than those reported in most other studies. Our data confirmed the previously published differences in the cognitive profiles of the two main PWS genotypes and offer new evidence to support this hypothesis. These results could guide future neuropsychological studies to determine the cognitive processing in PWS. This knowledge is essential to improve our understanding of gene-brain-behaviour relationships and to open new perspectives on therapeutic and educational programmes. [source] A Tale of Two Cases: Lessons for Education From the Study of Two Boys Living With Half Their BrainsMIND, BRAIN, AND EDUCATION, Issue 2 2007Mary Helen Immordino-Yang ABSTRACT, In recent years, educators have been looking increasingly to neuroscience to inform their understanding of how children's brain and cognitive development are shaped by their learning experiences. However, while this new interdisciplinary approach presents an unprecedented opportunity to explore and debate the educational implications of neuropsychological research, a good model for this dialogue is lacking. This is in part because relatively little is known about the relationships between cognitive, emotional, and neurological development, in part because of a dearth of research methods designed to rigorously connect issues of learning and development to neuropsychological strengths and weaknesses, and in part because neuropsychological studies are rarely presented in a format that is conducive to meaningful cross-disciplinary dialogue with educators. To begin to address these issues, in this article, I present the complementary cases of Nico and Brooke, two high-functioning adolescents, who have suffered the removal of an entire brain hemisphere (Nico his right and Brooke his left) to control severe epilepsy. Through presenting a neuropsychological study of these rare boys' emotion and affective prosody (vocal intonation) through the developmental lens of an educator, I reinterpret the neuropsychological findings for what they reveal about how the boys leveraged their emotional and cognitive strengths to learn important skills for which they were each missing half of the normally recruited neural hardware. While Nico's and Brooke's results seem on the surface to contradict expectations based on neuropsychological findings with adults, they combine to reveal a compensatory logic that begins to elucidate the active role of the learner as well as the organizing role of emotion in brain development, providing a jumping-off point for discussion between educators and neuroscientists and a model for connecting neuropsychological strengths and weaknesses to learning. [source] Differentiating vascular parkinsonism from idiopathic Parkinson's disease: A systematic review,,MOVEMENT DISORDERS, Issue 2 2010Seema Kalra MRCP Abstract Vascular parkinsonism (VP) remains a loose constellation of various clinical features. We systematically reviewed studies comparing clinical, neuroimaging and other investigations that might distinguish VP from idiopathic Parkinson's disease (PD). Medline, Embase, Cinahl (R), and PsycINFO were searched by querying appropriate key words. Reports were included if the study population contained comparative findings between patients with VP and PD. Twenty-five articles fulfilled the selection criteria. Patients with VP were older, with a shorter duration of illness, presented with symmetrical gait difficulties, were less responsive to levodopa, and were more prone to postural instability, falls, and dementia. Pyramidal signs, pseudobulbar palsy, and incontinence were more common in VP. Tremor was not a main feature of VP. Structural neuroimaging was more likely to be abnormal in VP (90,100% of cases) than in PD (12,43% of cases), but there was no specific abnormal structural imaging pattern for VP. Two studies of presynaptic striatal dopamine transporters (using single photon emission computed tomography) showed a significant reduction in striatal uptake ratios in PD but not in VP, whereas another study found that only the mean asymmetry index was significantly lower in VP. Various other investigations, including alternative imaging techniques, electrophysiological, and neuropsychological studies, are reported, but the diverse diagnostic criteria used makes it difficult to reach any firm conclusions. The development of accepted international diagnostic criteria for VP is urgently needed to facilitate further studies. © 2010 Movement Disorder Society [source] The development of arithmetical abilitiesTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 1 2005Brian Butterworth Background:, Arithmetical skills are essential to the effective exercise of citizenship in a numerate society. How these skills are acquired, or fail to be acquired, is of great importance not only to individual children but to the organisation of formal education and its role in society. Method:, The evidence on the normal and abnormal developmental progression of arithmetical abilities is reviewed; in particular, evidence for arithmetical ability arising from innate specific cognitive skills (innate numerosity) vs. general cognitive abilities (the Piagetian view) is compared. Results:, These include evidence from infancy research, neuropsychological studies of developmental dyscalculia, neuroimaging and genetics. The development of arithmetical abilities can be described in terms of the idea of numerosity , the number of objects in a set. Early arithmetic is usually thought of as the effects on numerosity of operations on sets such as set union. The child's concept of numerosity appears to be innate, as infants, even in the first week of life, seem to discriminate visual arrays on the basis of numerosity. Development can be seen in terms of an increasingly sophisticated understanding of numerosity and its implications, and in increasing skill in manipulating numerosities. The impairment in the capacity to learn arithmetic , dyscalculia , can be interpreted in many cases as a deficit in the concept in the child's concept of numerosity. The neuroanatomical bases of arithmetical development and other outstanding issues are discussed. Conclusions:, The evidence broadly supports the idea of an innate specific capacity for acquiring arithmetical skills, but the effects of the content of learning, and the timing of learning in the course of development, requires further investigation. [source] Bipolar depression: phenomenological overview and clinical characteristicsBIPOLAR DISORDERS, Issue 6 2004Philip B Mitchell Objectives:, There has been increasing interest in the depressed phase of bipolar disorder (bipolar depression). This paper aims to review the clinical characteristics of bipolar depression, focusing upon its prevalence and phenomenology, related neuropsychological dysfunction, suicidal behaviour, disability and treatment responsiveness. Methods:, Studies on the prevalence of depression in bipolar disorder, the comparative phenomenology of bipolar and unipolar depression, as well as neuropsychology and brain imaging studies, are reviewed. To identify relevant papers, a literature search using MEDLINE and PubMed was undertaken. Results:, Depression is the predominant mood disturbance in bipolar disorder, and most frequently presents as subsyndromal, minor or dysthymic depression. Compared with major depressive disorder (unipolar depression), bipolar depression is more likely to manifest with psychosis, melancholic symptoms, psychomotor retardation (in bipolar I disorder) and ,atypical' symptoms. The few neuropsychological studies undertaken indicate greater impairment in bipolar depression. Suicide rates are high in bipolar disorder, with suicidal ideation, suicide attempts and completed suicides all occurring predominantly in the depressed phase of this condition. Furthermore, the depressed phase (even subsyndromal) appears to be the major contributant to the disability related to this condition. Conclusions:, The significance of the depressed phase of bipolar disorder has been markedly underestimated. Bipolar depression accounts for most of the morbidity and mortality due to this illness. Current treatments have significant limitations. [source] |