Visuoperceptual disorders are a common consequence of brain disease. The Visual Form Discrimination Test is a task designed to assess the ability to make fine visual discriminations. Although its validity to assess the visuoperceptual impairments in patients with different neurological conditions has been well established, the normative data base for the test has remained small. The clinical use of the test has been limited by the scanty normative data available. Thus, with the aim of assisting the clinicians in interpreting more accurately the performances of their patients we investigated the test-retest reliability of the Benton’s VFDT and also provide normative data obtained on a sample of 397 healthy individuals.
1 July 2009 in Journal of the International Neuropsychological Society
It has been traditionally assumed that medial temporal lobe (MTL) is not required for working memory (WM). However, animal lesion and electrophysiological studies and human neuropsychological and neuroimaging studies have provided increasing evidences of a critical involvement of MTL in WM. Based on previous findings, the central aim of this study was to investigate the contribution of the MTL to verbal WM encoding. Here, we used magnetoencephalography (MEG) to compare the patterns of MTL activation of 9 epilepsy patients suffering from left hippocampal sclerosis with those of 10 healthy matched controls while they performed a verbal WM task. MEG recordings allow detailed tracking of the time course of MTL activation. We observed impaired WM performance associated with changes in the dynamics of MTL activity in epilepsy patients. Specifically, whereas patients showed decreased activity in damaged MTL, activity in the contralateral MTL was enhanced, an effect that became significant in the 600- to 700-ms interval after stimulus presentation. These findings strongly support the crucial contribution of MTL to verbal WM encoding and provide compelling evidence for the proposal that MTL contributes to both episodic memory and WM. Whether this pattern is signaling reorganization or a normal use of a damaged structure is discussed. (JINS, 2009, 15, 536–546.)
The verbal Selective Reminding Test (vSRT) is a frequently used test for evaluating verbal learning and memory. In the present study we investigated the construct validity of a Spanish version of the vSRT by determining its ability to distinguish between a group of healthy elderly subjects and a group of patients with dementia of the Alzheimer type (DAT). Further validation of the test was assessed by comparing the pattern of memory deficits found in the group of patients with DAT with findings from previous neuropsychological research concerning with memory impairments in English-speaking patients with Alzheimer’s disease. Analyses revealed that the test was able to differentiate normal individuals from patients with DAT. In addition the pattern of memory functioning found in the group of patients with DAT was consistent with findings of previous experimental and clinical reports. These results support the construct validity of the Spanish version of the vSRT.
The present study showed a higher amplitude for the late N1 and the PINV with reference to both the prediction performed in auditory paradigms of higher abstraction and the unexpected breaking of the extracted rules. Additionally, both components were modulated depending on the local probability, which would suggest that they are continuously being updated by the previous stimulus history.
1 December 2018 in International Journal of Psychophysiology