Segura-Torres P, Wagner U, Massanes-Rotger E, Aldavert-Vera L, Marti-Nicolovius M, Morgado-Bernal I
Departament de Psicobiologia i Metodologia en Ciències de la Salut Universitat Autonoma de Barcelona, Spain.
Behav Brain Res. 1996 Dec;82(1):113-7. doi: 10.1016/s0166-4328(97)81114-x.
To evaluate whether the tuberomammillary nucleus might be involved in the acquisition and/or retention of a two-way active avoidance conditioning, rats were given a unilateral lesion of the tuberomammillary nucleus (E2 region) 24 h prior to the first conditioning session. Four learning sessions were performed: one acquisition and 3 retention sessions (short-term, 24 h; and long-term, 8 and 18 days). Results showed that the lesion facilitated the long-term retention of conditioning, but no effects were observed on acquisition and short-term retention. Since rewarding intracranial electrical stimulation seems to be a consistent way to facilitate learning and memory processes, and tuberomammillary lesion has been shown to improve intracranial self-stimulation behavior (ICSS), we suggest that lesions in the present experiment could have facilitated two-way active avoidance retention by enhancing the function of brain reward mechanisms.
