Visuospatial representation in patients with mild cognitive impairment: Implication for rehabilitation.

Behavioral and neurophysiological experiments have demonstrated that distinct and common cognitive processes and associated neural substrates maintain allocentric and egocentric spatial representations. This review aimed to provide evidence from previous behavioral and neurophysiological studies on collating cognitive processes and associated neural substrates and linking them to the state of visuospatial representations in patients with mild cognitive impairment (MCI). Even though MCI patients showed impaired visuospatial attentional processing and working memory, previous neuropsychological experiments in MCI largely emphasized memory impairment and lacked substantiating evidence of whether memory impairment could be associated with how patients with MCI encode objects in space. The present review suggests that impaired memory capacity is linked to impaired allocentric representation in MCI patients. This review indicates that further research is needed to examine how the decline in visuospatial attentional resources during allocentric coding of space could be linked to working memory impairment.

Intra Parietal Sulcus Area 1-2 and Angular Gyrus Differentiates Visual Short-Term Memory and Sustained Attention Activities.

Background: Visual short-term memory (VSTM) and attention were found to modulate neural activity predominantly in a superior parietal lobule. This is thought to be the selective attention importance for encoding and manipulation in VSTM. The major area of investigation mainly rested with the differences in the neural substrates and networks mediating these cognitive processes in near and far cortical structures. Summary: Based on previous investigations, the dynamic temporal window route of attention and time locked associated cognitive processes and sub-processes are sketched and its implication in VSTM study is discussed. Imaging cortical structures to isolate closely linked cognitive tasks require circumscribing to certain time-windows in which the paradigm should support to tap time-locked associated processes and sub-processes. Key Messages: The neural activities in intraparietal sulcus area 1-2 and angular gyrus during VSTM encoding are beyond the modulatory effects of selective and sustained attention.