Intracranial self-stimulation also facilitates learning in a visual discrimination task in the Morris water maze in rats

Abstract

Intracranial self-Stimulation (ICSS) of the medial forebrain bundle is a treatment capable of consistently facilitating acquisition of learning and memory in a wide array of experimental paradigms in rats. However, the evidence supporting this effect on implicit memory comes mainly from classical conditioning and avoidance tasks. The present work aims to determine whether ICSS would also improve the performance of rats in another type of implicit task such as cued simultaneous visual discrimination in the Morris Water Maze. The ICSS treatment was administered immediately after each of the five acquisition sessions and its effects on retention and reversal were evaluated 72h later. Results showed that ICSS subjects committed fewer errors than Sham subjects and adopted more accurate trajectories during the acquisition of the task. This improvement was maintained until the probe test at 72h. However, ICSS animals experienced more difficulties than the Sham group during the reversal of the same learning, reflecting an impairment in cognitive flexibility. We conclude that post-training ICSS could also be an effective treatment for improving implicit visual discrimination learning and memory.

Orexin-1 receptor blockade differentially affects spatial and visual discrimination memory facilitation by intracranial self-stimulation

“…Results obtained in this report indicate that ICSS is a treatment capable of facilitating both spatial and visual discrimination in the MWM, confirming the general boosting effects of ICSS on different types of memory Chamorro-López et al, 2015;García-Brito et al, 2017). The facilitating effects of ICSS on the acquisition phase of the SVD task confirm previous findings (García-Brito et al, 2017), which reported that ICSS-treated animals solve the SVD task faster than the controls. Such a clear difference between groups was not observed for the spatial task.…”

“…The average intertrial interval (ITI) was 120s. A detailed protocol of the cues' manipulation can be found in a previous report (García-Brito et al, 2017).…”

“…Intracranial self-stimulation (ICSS) is an operant response in which subjects selfadminister electrical stimulation to brain areas belonging to the reward system. As a treatment, ICSS to the medial forebrain bundle (MFB) in the lateral hypothalamus (LH) is capable of facilitating the acquisition and retention of implicit (Huston et al, 1977;Huston & Mueller, 1978;Redolar-Ripoll et al, 2002;García-Brito et al, 2017) and explicit (Soriano-Mas et al, 2005;Chamorro-López et al, 2015) memory tasks in rats, even managing to recover lost memory function caused by electrolytic brain lesions (Segura-Torres et al, 2010;Kádár et al, 2014) and old age (Aldavert-Vera et al, 1997).…”

Brain and Cognition for Addiction Medicine: From Prevention to Recovery Neural Substrates for Treatment of Psychostimulant-Induced Cognitive Deficits

“…Similarly, DBS of the ventromedial PFC resulted in improvement in novel object recognition memory compared with that in controls in animals (284). Intracranial DBS also improved spatial memory in rats as assessed using the Morris water maze task (285). Also, DBS facilitated extinction of fear-associated memories (286, 287).…”

Arc protein expression after unilateral intracranial self-stimulation of the medial forebrain bundle is upregulated in specific nuclei of memory-related areas

“…This could explain the wide therapeutic effects that MFB-ICSS appears to have in relation to different memory types. In addition to explicit memory, MFB-ICSS also improves performance in implicit memory tasks [ 10 – 12 ]. Most notable are the effects on emotional memory as measured by amygdala-dependent active avoidance tasks, in which ICSS reverses the memory deficit caused by aging [ 13 , 14 ] and/or brain damage [ 15 , 16 ].…”