Age-related neural activity during allocentric spatial memory

Abstract

Age-related decline in allocentric (viewer-independent) spatial memory is seen across species. We employed a virtual reality analogue of the Morris Water Maze to study the effect of healthy ageing on neural activity during allocentric spatial memory using functional magnetic resonance imaging. Voxel-based morphometry was used to ascertain hippocampal volumetric integrity. A widespread neural network comprising frontal, parietal, occipital, thalamic, and cerebellar regions was activated in young and older adults, but only young adults significantly activated bilateral hippocampus and left parahippocampus, as well as right frontal pole and dorso-lateral prefrontal cortex (DLPFC) during encoding and right DLPC during retrieval. Hippocampal grey matter volume was unchanged in older adults; however, prefrontal and parahippocampal functional attenuation was accompanied by volumetric reduction. We conclude that the decline in allocentric spatial memory with age is associated with attenuated hippocampal function, as well as compromised function and structure of prefrontal and parahippocampal regions.

Cortical thickness changes following spatial navigation training in adulthood and aging

“…Older rats are generally impaired in navigation performance compared to younger rats (Barnes, 1979;Begega et al, 2001;Ingram, 1988;McLay et al, 1999), and younger adults outperform their older counterparts in spatial navigation tasks (Driscoll et al, 2005;Lövdén et al, 2005b; NeuroImage 59 (2012) 3389-3397 Mahmood et al, 2009;Moffat et al, 2001;Newman and Kaszniak, 2000;Wilkniss et al, 1997). Functional imaging studies have shown that older adults exhibit reduced hippocampal activation during navigation tasks compared to younger adults (Antanova et al, 2009;Moffat et al, 2006), which is consistent with findings suggesting that older adults rely more on egocentric processes (Lövdén et al, 2005a;Rodgers et al, in press). In line with these patterns, older adults report avoiding unfamiliar routes and places (Burns, 1999), which may lead to a less engaged lifestyle that in turn further affects cognitive performance in old age (Hertzog et al, 2009;Lövdén et al, 2005a).…”

Spatial Navigation Impairment in Healthy Aging and Alzheimer’s Disease

“…The findings were interpreted as aging dependent compensatory shift from more posterior and medial temporal systems supporting navigation to more anterior frontal systems. Contrasting activation pattern was found in the only fMRI study in virtual MWM in elderly subjects (Antonova et al, 2009). Differently from younger group, the elderly adults did not activate hippocampal-parahippocampal region either during encoding or retrieval and also lacked activation of the frontal pole and dorsolateral prefrontal cortex.…”

Temporal Order Memory Assessed during Spatiotemporal Navigation As a Behavioral Cognitive Marker for Differential Alzheimer's Disease Diagnosis

“…Studies assessing spatial memory in aging and pathology have mostly focused on allocentric spatial processing (Moffat and Resnick, 2002;Cushman et al, 2008;Antonova et al, 2009). Here, we additionally focused on the temporal aspect of navigation (Eichenbaum, 2004;Fouquet et al, 2010).…”