Abstract
We examined the effects of excitatory amino acid (EAA) lesions of the nucleus basalis magnocellularis (NBM) in young (3-month-old), adult (9-month-old), and aged (24-month-old) rats on the expression of conditioned freezing to an environmental context and to a discrete conditioned stimulus (CS; tone) in a Pavlovian fear-conditioning task. Lesions caused by injections of NMDA resulted in reductions in the levels of conditioned freezing to the context (Skinner box) in each age group, while freezing levels displayed during the presentation of the tone were unaffected. In addition, a significant decline in the levels of freezing to context, but not to the tone, was found in the 24-month-old age group. These results suggest that the nucleus basalis plays a role in the expression of conditioned fear to environmental context and in the behavioral changes associated with the normal aging process, and that the vulnerability of these cells to excitotoxic damage, and the resulting behavioral deficit, increases with age.
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Stoehr, J.D., Wenk, G.L. Effects of age and lesions of the nucleus basalis on contextual fear conditioning. Psychobiology 23, 173–177 (1995). https://doi.org/10.3758/BF03332019
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DOI: https://doi.org/10.3758/BF03332019