Entorhinal volume, aerobic fitness, and recognition memory in healthy young adults: A voxel-based morphometry study

Abstract

Converging evidence supports the hypothesis effects of aerobic exercise and environmental enrichment are beneficial for cognition, in particular for hippocampus-supported learning and memory. Recent work in humans suggests exercise training induces changes in hippocampal volume, but it is not known if aerobic exercise and fitness also impact the entorhinal cortex. In animal models, aerobic exercise increases expression of growth factors, including brain derived neurotrophic factor (BDNF). This exercise-enhanced expression of growth hormones may boost synaptic plasticity, and neuronal survival and differentiation, potentially supporting function and structure in brain areas including but not limited to the hippocampus. Here, using voxel based morphometry and a standard graded treadmill test to determine cardio-respiratory fitness (Bruce protocol; VO2 max), we examined if entorhinal and hippocampal volumes were associated with cardio-respiratory fitness in healthy young adults (N = 33). In addition, we examined if volumes were modulated by recognition memory performance and by serum BDNF, a putative marker of synaptic plasticity. Our results show a positive association between volume in right entorhinal cortex and cardio-respiratory fitness. In addition, average gray matter volume in the entorhinal cortex, bilaterally, was positively associated with memory performance. These data extend prior work on the cerebral effects of aerobic exercise and fitness to the entorhinal cortex in healthy young adults thus providing compelling evidence for a relationship between aerobic fitness and structure of the medial temporal lobe memory system.

Cardiorespiratory fitness is differentially associated with cortical thickness in young and older adults

“…Results of the current study extend findings of a negative association between CRF and cortical thickness to young adults and demonstrate that young adulthood is also a period in which enhanced CRF may benefit brain structure. Nevertheless, such findings may be region-specific, as a recent voxel-based morphometry study focusing on the medial temporal lobes observed a positive association between peak VO 2 and right entorhinal volume in young adults (Whiteman et al, 2016). Additional studies are needed to further delineate the relationship between CRF and brain structure in young adults.…”

The Brain and Movement: How Physical Activity Affects the Brain

“…Th e same research group (Chaddock et al, 2010b) demonstrated through functional magnetic resonance a positive correlation between increased hippocampal volume and mnestic performance in pre-adolescent children who performed regular exercise (Alesi et al, 2015). Whiteman, Young, Budson, Stern and Schon (2016) further demonstrated how aerobic activity aff ects a particular area in the hippocampus called the entorhinal cortex. Researchers have shown that aerobic activity is related to an increase in grey matter in the entorhinal cortex, through which information travels.…”

On the Run for Hippocampal Plasticity

“…Intervention studies show that aerobic training 3 days per week for at least 3 months to 1 year can prevent and/or reverse the age-related decline in hippocampal volume (Erickson et al 2011;Maass et al 2015; ten Brinke et al 2015). Interestingly, the exercise-induced increase in grey matter volume seems to occur in the hippocampus (Maass et al 2015; Duzel et al 2016), entorhinal (Whiteman et al 2016), and prefrontal cortex (Erickson et al 2014), with no change in the thalamus or caudate nucleus (Erickson et al 2011). …”