Rapid visual memory decay in mild cognitive impairment

Rapid visual memory decay in mild cognitive impairment Source: http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=547895 Zhong-Lin Lu et al. report that the rapid decay of iconic (visual short-term) memory appears to be a general characteristic of mild cognitive impairment, which often precedes the onset of Alzheimer's disease. Iconic memory typically lasts only a fraction of a second before it is either lost or stored in short-term memory, and a link between iconic memory impairment and Alzheimer's disease has been suggested. The authors tested the iconic memory of 23 young adults (average age, 20 years), 11 older adults with mild cognitive impairment (average age, 85 years), and 16 older controls (average age, 82 years). Iconic memory was characterized by using the partial report paradigm with the same visual stimuli parameters in each observation group. The researchers found that mean iconic memory duration was significantly shorter in subjects with mild cognitive impairment (0.07 s), compared with both older (0.30 s) and younger (0.34 s) controls. In a series of conventional neuropsychological tests used to assess cognitive function, the mild cognitive impairment group performed significantly worse than the older control group. In both of these groups, no significant performance differences were observed in visual and task abilities or the ability to transfer items to short-term memory. The authors suggest that testing iconic memory could be used with other measures to aid the diagnosis of Alzheimer's disease. “Fast decay of iconic memory in observers with mild cognitive impairments” by Zhong-Lin Lu, James Neuse, Stephen Madigan, and Barbara Anne Dosher (see pages 1797-1802)

​ Figure 1 Native-state conformations of α-synuclein. Figure 2 VP branching morphology of ERα-/- mice. Figure 3 Mast cell degranulation induced by light chains. Figure 4 Cholera phage types.