Exercise enhances memory consolidation in the aging brain

Abstract

Exercise has been shown to reduce age-related losses in cognitive function including learning and memory, but the mechanisms underlying this effect remain poorly understood. Memory formation occurs in stages that include an initial acquisition phase, an intermediate labile phase, and then a process of consolidation which leads to long-term memory formation. An effective way to examine the mechanism by which exercise improves memory is to introduce the intervention (exercise), post-acquisition, making it possible to selectively examine memory storage and consolidation. Accordingly we evaluated the effects of post-trial exercise (10 min on a treadmill) on memory consolidation in aged canines both right after, an hour after, and 24 h after acute exercise training in concurrent discrimination, object location memory (OLM), and novel object recognition tasks. Our study shows that post-trial exercise facilitates memory function by improving memory consolidation in aged animals in a time-dependent manner. The improvements were significant at 24 h post-exercise and not right after or 1 h after exercise. Aged animals were also tested following chronic exercise (10 min/day for 14 consecutive days) on OLM or till criterion were reached (for reversal learning task). We found improvements from a chronic exercise design in both the object location and reversal learning tasks. Our studies suggest that mechanisms to improve overall consolidation and cognitive function remain accessible even with progressing age and can be re-engaged by both acute and chronic exercise.

Neuroinflammation in the normal aging hippocampus

“…Many studies have recently reported robust effects of physical exercise in aged animals on hippocampal neurogenesis and hippocampal memory performance (Kim et al, 2010; Barrientos et al, 2011; Kohman et al, 2012; Speisman et al, 2013; Merkley et al, 2014; Snigdha et al, 2014). For example, one study showed that 12 weeks of voluntary wheel running reversed the aging-associated memory deficits in the hippocampal-dependent task of place recognition (Siette et al, 2013).…”

Playful activity post-learning improves training performance in Labrador Retriever dogs ( Canis lupus familiaris )

“…Individual variability of learning and memory can also have a confounding effect on results (Snigdha et al, 2014). In this study population, a significant effect was seen for the pretraining and the absolute trials on day 1 data.…”

“…Additionally, acute exercise post-learning improved memory recall of some training tasks in senior dogs (Snigdha et al, 2014). For this reason, we cannot exclude that an exercise component of the arousing playful activity intervention contributed to the improved training performance.…”

“…The results show that engaging in playful activity for 30 minutes after successfully learning the task improved re-training performance, evidenced by fewer trials needed to meet task criteria 24 hours after initial acquisition. This significant difference between the two groups not only suggests that the intervention is affecting long-term memory rather than an improved short-term memory (Larra et al, 2014;Nielsen et al, 2005;Preuß and Wolf, 2009;Snigdha et al, 2014), but also that pleasant arousal post-learning has similar effects on enhancing memory in dogs as it does in humans (Esmaeili et al, 2002;Liu et al, 2008).…”

The Influence of Three-Week Aerobic Exercise Program on Neurodynamic Parameters of Patients Underwent Coronary Bypass Grafting

“…Langlois F, et al описали улучшение ког-нитивной функции среди пациентов пожилого возра-ста на фоне трехмесячного курса физических трени-ровок [8]. В экспериментах показано, что физические аэробные упражнения способствуют снижению функционального дефицита, связанного с когнитив-ным старением, тем самым повышая устойчивость головного мозга к старению [9]. Известно, что влияние физических тренировок на больных с сердечно-сосудистой патологией носит многоплановый характер [10].…”