Differential effects of parafascicular electrical stimulation on active avoidance depending on the retention time, in rats

• Published in: Brain research bulletin Vol. 52; no. 5; pp. 419 - 426
• Main Authors: Sos-Hinojosa, Hermenegildo, Vale-Martı́nez, Anna, Guillazo-Blanch, Gemma, Martı́-Nicolovius, Margarita, Nadal-Alemany, Roser, Morgado-Bernal, Ignacio
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY Elsevier Inc 15.07.2000; Elsevier Science
• Subjects: Analysis of Variance; Anatomical correlates of behavior; Animals; Avoidance Learning - physiology; Behavioral psychophysiology; Biological and medical sciences; Electric Stimulation; Electrodes, Implanted; Fundamental and applied biological sciences. Psychology; Intracranial electrical stimulation; Intralaminar nuclei; Intralaminar Thalamic Nuclei - anatomy & histology; Intralaminar Thalamic Nuclei - physiology; Learning and memory; Male; Motor Activity - physiology; Parafascicular nucleus; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Rat; Rats; Rats, Wistar; Reaction Time - physiology; Regression Analysis; Retention (Psychology) - physiology; Survival Analysis; Time Factors; Two-way active avoidance; Learning and memory; Intracranial electrical stimulation; Parafascicular nucleus; Two-way active avoidance; Rat; Intralaminar nuclei; Memory; Electrical stimulus; Rodentia; Central nervous system; Learning; Vertebrata; Mammalia; Acquisition process; Animal; Thalamus; Avoidance; Brain (vertebrata)
• ISSN: 0361-9230; 1873-2747
• DOI: 10.1016/S0361-9230(00)00280-X

To evaluate whether electrical stimulation of the parafascicular nucleus of the thalamus can improve short-term (24 h) and/or long-term (11 days) retention of two-way active avoidance, rats were implanted with an electrode at this nucleus (experimental groups with stimulation in the parafascicular, and control groups without stimulation) or above it (other control groups without stimulation). After a single 30-trial acquisition session, experimental groups were submitted to a 20-min session of electrical stimulation. Results showed that parafascicular stimulation improved the 24-h retention of the task (number of avoidances made), increasing also the percentage of subjects that achieved a learning criterion and reducing the number of trials needed to reach it. In contrast, no differences among groups were found on the 11-day retention test. The present results agree with previous data showing a short-term effect of parafascicular stimulation on retention, and confirm its involvement in learning and memory modulation. These data are discussed in the context of the acceleration and strengthening of the memory by activation of arousal systems, and/or specific cortical-striatal systems.