Localization of a “passive avoidance memory system”in the white rat

Abstract

Adult rats, previously trained to refrain from entering a small dark compartment from a large illuminated compartment, sustained lesions to 1 of 53 different brain sites and were subsequently tested for retention. Retention losses were associated with lesions to the neocortex, most elements of the limbic forebrain and basal ganglia, medial portions of the thalamus and hypothalamus, colliculi, median raphe, and cerebellum. Most of these structures were also found to be critical for retention of an active avoidance habit. It was hypothesized that avoidance habits depend upon the activities of four functional blocks of the brain: the first block (basal ganglia) is concerned with sensorimotor integration, the second block (dorsal midbrain, posterior thalamus, amygdala, nucleus accumbens, and frontal cortex) plays a role in fear-initiated responses, the third block (cerebellum, anterior and ventromedial thalamus, and parietal cortex) has somatosensory functions, and the fourth block (occipital cortex, hippocampal complex, and mamillary bodies) is involved with cognitive mapping. These functional blocks require the engagement of an inhibitory mechanism (medial hypothalamus and median raphe) or an excitatory mechanism (brainstem reticular formation and anterior cingulate cortex) in order to support passive and active avoidance habits, respectively.

Detour problem-solving behavior in rats with neocortical and hippocampal lesions: A study of response flexibility

“…This would follow from the fact that the latter would also disrupt hippocampal function to the extent that the hippocampus would be deprived of certain kinds of sensory input necessary to transact its comparator role. This account would seem to explain the similar disturbances observed in neocortically and hippocampally damaged rats on such tasks as complex mazes (Foreman & Stevens, 1982;Thompson, 1979), position reversals (Thompson, 1983), and active and passive avoidance responses (Thompson, 1978b).…”

“…Rats with hippocampal or neocorticallesions have been characterized, at one time or another, as showing a disturbance in response inhibition (Douglas, 1967;Gray, 1982;Thompson, 1978b), recent ("working") memory (Lashley, 1929;Olton & Papas, 1979), behavioral exploration (Lashley, 1935;O'Keefe & Nadel, 1978), and/or attention (Lashley, 1935;Oades, 1982). Any one of these disturbances could underlie the reduction in response flexibility reported in the current experiment.…”

Deficits in response inhibition and attention in rats rendered mentally retarded by early subcortical brain damage

“…However, evidence supporting the existence of an inhibitory deficit in these subcortically lesioned rats comes from other sources as well. For example, rats with damage to any one of the subcortical sites studied in the current experiment have been reported to show impairments in spatial reversal learning (Thompson, 1983) and those with damage to the GP, SN, or MR have been found to show retention impairments of a passive avoidance response (Thompson, 1978b). Tasks of this sort have likewise been viewed as being sensitive to an inhibitory deficit (Warburton, 1977).…”

“…For example, the hippocampus of rodents has been implicated in both inhibitory (Douglas, 1967) and attentional (Oades, 1982) processes; yet young or adult rats with hippocampal lesions do not exhibit a generalized learning impairment (Douglas, 1967;Thompson, 1982a;Thompson & Yu, 1983). Other brain regions, to mention a few, which have been implicated in one or both of these processes include the frontal cortex (Stuss Thompson, 1978b), amygdala (Nagel & Kemble, 1976;Thompson, 1978b), and lateral lemniscal midbrain area (Sprague, Levitt, Robson, Liu, Stellar, & Chambers, 1963). Again, damage to these regions in young or adult rats does not result in a generalized learning impairment (Thompson, 1982a(Thompson, , 1983Thompson, Ramsay, & Yu, 1984).…”

BDNF–triggered events in the rat hippocampus are required for both short‐ and long‐term memory formation

“…This fear-motivated learning is an hippocampal-dependent task that is acquired in a single and brief training session (Winocur and Bindra, 1976;Thompson, 1977;Gold, 1986;Lorenzini et al, 1996;Taubenfeld et al, 1999), which makes it ideal for investigating the role of signaling pathways initiated during memory processing without the interference from retrieval of the learned behavior that might occur in multitrial tasks .…”