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Memory Components (memory + component)
Selected AbstractsA neural network critical for spelling,ANNALS OF NEUROLOGY, Issue 2 2009Lauren Cloutman PhD We aimed to identify neuroanatomical regions associated with deficits to the graphemic buffer, a working memory component of the spelling system that holds the sequence of letter identities during production. We evaluated 331 patients with left hemisphere ischemic stroke with various spelling tests and magnetic resonance diffusion-weighted imaging and perfusion-weighted imaging, within 48 hours of stroke onset. A voxel-wise statistical map showed that ischemia in voxels in posterior and inferior frontal and parietal cortex, subcortical white matter underlying prefrontal cortex, lateral occipital gyrus, or caudate was associated with impairment in maintaining the sequence of letter identities while spelling. Ann Neurol 2009;66:249,253 [source] Neural basis for sentence comprehension: Grammatical and short-term memory componentsHUMAN BRAIN MAPPING, Issue 2 2002Ayanna Cooke Abstract We monitored regional cerebral activity with BOLD fMRI while subjects were presented written sentences differing in their grammatical structure (subject-relative or object-relative center-embedded clauses) and their short-term memory demands (short or long antecedent-gap linkages). A core region of left posterior superior temporal cortex was recruited during all sentence conditions in comparison to a pseudofont baseline, suggesting that this area plays a central role in sustaining comprehension that is common to all sentences. Right posterior superior temporal cortex was recruited during sentences with long compared to short antecedent-gap linkages regardless of grammatical structure, suggesting that this brain region supports passive short-term memory during sentence comprehension. Recruitment of left inferior frontal cortex was most clearly associated with sentences that featured both an object-relative clause and a long antecedent-gap linkage, suggesting that this region supports the cognitive resources required to maintain long-distance syntactic dependencies during the comprehension of grammatically complex sentences. Hum. Brain Mapping 15:80,94, 2001. © 2001 Wiley-Liss, Inc. [source] Changes in explicit memory associated with early dementia in adults with Down's syndromeJOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 3 2002S. J. Krinsky-McHale Abstract Background A modified version of the Selective Reminding Test (SRT) (Buschke 1973) was used to examine the changes in memory that occur with early-stage dementia of the Alzheimer's type (DAT) in adults with intellectual disability (ID) and Down's syndrome (DS), and to compare these changes to those occurring with ,normal' ageing. Method Hierarchical linear modelling analyses showed steep declines in the performance of participants who had met the criteria for the onset of DAT. Non-demented participants also showed declines in performance which were related to their age. However, the absolute magnitude of these declines was consistent with a ,normal' ageing pattern and not with undetected dementia. Results In analysing the specific memory components that are compromised, the present authors found that participants with early-stage DAT showed severely diminished long-term storage and retrieval processing abilities compared to their non-demented peers. Notably, these declines preceded other symptoms of dementia, in most cases by more than a full year and sometimes by as much as 3 years. Conclusions Thus, the present results clearly confirm that memory processes are affected during early dementia in adults with DS, and that the SRT has promise as a clinical tool. [source] Genuine Episodic Memory Deficits and Executive Dysfunctions in Alcoholic Subjects Early in AbstinenceALCOHOLISM, Issue 7 2007Anne Lise Pitel Background: Chronic alcoholism is known to impair episodic memory function, but the specific nature of this impairment is still unclear. Moreover, it has never been established whether episodic memory deficit in alcoholism is an intrinsic memory deficit or whether it has an executive origin. Thus, the objectives are to specify which episodic memory processes are impaired early in abstinence from alcohol and to determine whether they should be regarded as genuine memory deficits or rather as the indirect consequences of executive impairments. Methods: Forty recently detoxified alcoholic inpatients at alcohol entry treatment and 55 group-matched controls underwent a neuropsychological assessment of episodic memory and executive functions. The episodic memory evaluation consisted of 3 tasks complementing each other designed to measure the different episodic memory components (learning, storage, encoding and retrieval, contextual memory, and autonoetic consciousness) and 5 executive tasks testing capacities of organization, inhibition, flexibility, updating, and integration. Results: Compared with control subjects, alcoholic patients presented impaired learning abilities, encoding processes, retrieval processes, contextual memory and autonoetic consciousness. However, there was no difference between the 2 groups regarding the storage capacities assessed by the rate of forgetting. Concerning executive functions, alcoholic subjects displayed deficits in each executive task used. Nevertheless, stepwise regression analyses showed that only performances on fluency tasks were significantly predictive of some of the episodic memory disorders (learning abilities for 40%, encoding processes for 20%, temporal memory for 21%, and state of consciousness associated with memories for 26%) in the alcoholic group. Discussion: At alcohol treatment entry, alcoholic patients present genuine episodic memory deficits that cannot be regarded solely as the consequences of executive dysfunctions. These results are in accordance with neuroimaging findings showing hippocampal atrophy. Moreover, given the involvement of episodic memory and executive functions in alcohol treatment, these data could have clinical implications. [source] Cross-cultural assessment of the Contextual Memory Test (CMT)OCCUPATIONAL THERAPY INTERNATIONAL, Issue 4 2000Health Studies, Naomi Josman PhD, OTR Faculty of Social Welfare Abstract The Contextual Memory Test (CMT) measures aspects of memory and metamemory of people with cognitive disabilities. The assessment tool was originally developed and standardized in the United States. The objectives of this study were: (1) to evaluate the applicability of the CMT to an Israeli population; (2) to further investigate the construct validity of the CMT to discriminate among age groups; and (3) to analyse the 40 items on the CMT from a cultural point of view. The CMT was administered to 217 typical Israeli adults, grouped into three age categories, closely matching those in the US normative study (Toglia, 1993). Similar levels of performance were obtained for Israelis and Americans on the various test components. Statistically significant differences between American and Israeli subjects' performance levels were evident in three memory components in the elderly groups (group 3) and in only two memory components in the young group (group 1). In addition, within-sample comparisons of the three Israeli age groups yielded significant age effects for recall, recognition, strategy use and general awareness. This study confirmed discriminant validity for the CMT. The tool seems to be highly appropriate for use by occupational therapists in assessing memory and metamemory with American and Israeli adult subjects. The relatively small size of the age groups and the lack of random selection of subjects are limitations of this study. Therefore, it is recommended that the study be replicated with a larger and randomized sample. The multifaceted nature of the assessment provides much more information than traditional recall scores, and the metamemory components enhance both differential diagnosis and appropriate planning of treatment. Copyright © 2000 Whurr Publishers Ltd. [source] | ||||||||||