Effects of acute and chronic physical exercise and stress on different types of memory in rats

Abstract

Here we study the effect of acute and chronic physical exercise in a treadmill and of daily stress (because forced exercise involves a degree of stress) during 2 or 8 weeks on different types of memory in male Wistar rats. The memory tests employed were: habituation in an open field, object recognition and spatial learning in the Morris water maze. Daily foot-shock stress enhanced habituation learning after 2 but not after 8 weeks; it hindered both short- (STM) and long-term memory (LTM) of the recognition task at 2 weeks but only STM after 8 weeks and had no effect on spatial learning after either 2 or 8 weeks. Acute but not chronic exercise also enhanced habituation in the open field and hindered STM and LTM in the recognition task. Chronic exercise enhanced one important measure of spatial learning (latency to escape) but not others. Our findings indicate that some care must be taken when interpreting effects of forced exercise on brain parameters since at least part of them may be due to the stress inherent to the training procedure.

Investigation of the long term effects of chronic white noise stress on learning in radial arm maze and behaviors in forced swim test

“…In accordance with our results Mello et al (19) did not found any effects of, daily exposure to 5 min mild foot shock stress for both 2 and 8 weeks on memory acquisition and retention. Moreover, it was also reported that only rats exposed to 6h/ 21d restraint paradigm showed consistent spatial memory deficits, but the same stress application for 2h/10d, 2h/21d and 6h/10 d did not have any effect on cognition (18).…”

The Effect of Exercise on Learning and Spatial Memory Following Stress-Induced Sleep Deprivation (Sleep REM) in Rats

“…Research has also found that exercise has little effect in improving memory and does not affect object recognition tasks (13). While the majority of studies used voluntary exercise, in the current investigation, low-intensity forced exercise was used, which is similar to exercise for human studies where not well known (18).…”

“…For example, Mello et al (13) studied the effect of vigorous physical activity for two weeks and longterm treadmill exercise combined with daily stress (due to a little stress associated with forced physical activity) for eight weeks on the different aspects of memory in rats. The results showed that stress and physical activity (severe or prolonged) do not affect the acquisition and retention of animals.…”

The influence of enriched environment on spatial memory in Swiss mice of different ages

“…However, complex enrichment applied over brief periods seems to benefit mice starting only at middle age 8 when memory decline begins. Nevertheless, physical stimulation seems to benefit spatial memory at ages when there is still no memory impairment 22 , likely by promoting changes in glial cells involved in synaptic remodeling and affecting brain plasticity 23 . Studies that used more than one running wheel in their EE protocol reported positive results 8,9,10 .…”