Enriched environment effects on behavior, memory and BDNF in low and high exploratory mice

Abstract

Environmental enrichment (EE) has been largely used to investigate behavioral modifications and neuroplasticity in the adult brain both in normal and pathological conditions. The interaction between individual behavioral traits with EE responsiveness has not been investigated within the same strain. By using two extremes of CF1 mice that differ by their exploratory behavior in the Open Field (OF) task (Kazlauckas V, 2005), denominated as Low (LE) and High (HE) Exploratory Mice, the present study evaluated if EE during adulthood could modify the putative differences between LE and HE mice on exploratory behavior, memory performance and hippocampal BDNF levels. To this end, we investigated the effect of adult LE and HE mice after 2 months of enriched or standard housing conditions on the open field, on novel object recognition, on the inhibitory avoidance task and on hippocampal BDNF immunocontent. LE showed low exploratory behavior, less retention in the inhibitory avoidance and lower hippocampal BDNF levels. EE enhanced exploratory behavior, memory performance and hippocampal BDNF levels both in LE and HE mice. Importantly, the general profile of LE mice submitted to EE was similar to HE mice housed in standard conditions. These results show that internalized behavior of LE mice can be significantly modified by exposure to an enriched environment even during adulthood. These observations may contribute to investigate biological mechanisms and therapeutical interventions for individuals with internalized psychiatric disorders.

Environmental enrichment and the sensory brain: the role of enrichment in remediating brain injury

“…In a similar vein, the consensus (Nithianantharajah and Hannan, 2006; Kazlauckas et al, 2011; Landers et al, 2011) is that EE encourages activity and exploratory behavior though there are some inconsistencies: some studies show increased activity in novel environments (Benaroya-Milshtein et al, 2004), and others show faster habituation and less activity (Zimmermann et al, 2001; Schrijver et al, 2002; Elliott and Grunberg, 2005), when compared with animals housed in standard or impoverished environments (Varty et al, 2000; Zimmermann et al, 2001). Recently, Zebunke et al (2013) showed a decrease in general activity during an open field test, with an increase in duration of exploration of novel objects by pigs exposed to cognitive enrichment.…”

Gene expression patterns and environmental enrichment-induced effects in the hippocampi of mice suggest importance of Lsamp in plasticity

“…The elevation of BDNF specifically in the hippocampus is one of the most extensively described molecular changes (Kazlauckas et al, 2011; Kuzumaki et al, 2011; Chourbaji et al, 2012) induced by environmental enrichment. The results of the current study confirmed that effect.…”

Auditory map reorganization and pitch discrimination in adult rats chronically exposed to low-level ambient noise

“…Equally plausible is remodeling of the excitatory connections in the A1 that gives rise to the large-scale reorganization of tonotopic map. Many studies have demonstrated the structural remodeling of neural circuits induced by experience through a variety of mechanisms (Barnes and Finnerty, 2010) such as axonal growth (Debello et al, 2001), synapse genesis (Foscarin et al, 2011), change in firing property (Miller et al, 2011), and modifications in neurotransmitter and/or neuromodulator systems (Rebola et al, 2010; Kazlauckas et al, 2011; Salgado et al, 2011). …”