Detection of a sensory stimulus depends on its psychophysical saliency; the higher the saliency, the easier the detection. But it is not known whether sensory relay nuclei differ in their ability to detect low salient whisker stimuli. We found that reversible lesions of either the somatosensory thalamus or superior colliculus blocked detection of a low salience whisker conditioned stimulus (WCS...

Two different measures of the retention of avoidance conditioning, frequently used in the investigation of retrograde anmesia (RA), were examined. Rats were given a single training trial on either passive or active avoidance in a conventional black-white discrimination apparatus and step•through latencies were recorded. Task sequence, footshock and hypothermia were experimentally varied across ...

To clarify the role of the amygdala in the fulfillment of memory and/or learning, amygdala-lesioned mice were tested in passive and active avoidance performances and also in spatial learning tasks. Although the lesioned animals showed deteriorated performances in both passive and active avoidance tests, they executed the spatial learning tasks as well as the control mice. The learning deficit w...

Normal controls and schizophrenic patients on propranolol as sole drug or combined with neuroleptics showed superior active and passive avoidance learning to schizophrenic patients who were medicated with conventional neuroleptics only. Active avoidance involved responding quickly, passive avoidance withholding a response to avoid an unpleasant noise and reacting to the appropriate stimulus. Th...

The authors examined the relationships between 2 "personality" dimensions (Approach and Fear Avoidance) and 2-way active avoidance learning performance in the guppy (Poecilia reticulata). Contrary to expectations (based on prior rodent studies), higher fearfulness facilitated both earlier appearance and acquisition of the shuttlebox avoidance responses, especially in the less exploratory and ac...

Previous studies have shown that autoimmune mice perform very poorly on active avoidance learning tasks. In the current studies, mice with lupus-like systemic autoimmunity were able to learn active, as well as passive, avoidance protocols with shock as reinforcement. Therefore, the behavioral deficits seen in active avoidance tasks are not a consequence of the use of electric shock. Rather, the...

BACKGROUND AND PURPOSE The purpose of this study was to investigate the behavioral changes, in particular retention of memory, after focal cerebral ischemia in rats. METHODS Ischemia was produced by permanent occlusion of the left middle cerebral artery (MCA). For quantitative behavioral analysis, one-trial passive avoidance response and active avoidance response with the discrete lever-press...

Active and passive avoidance behaviors involve either emitting or omitting a response to avoid potential harm. Both are key components in the etiology and maintenance of anxiety disorders, yet the neural circuitry that mediates avoidance is underexplored. Using functional magnetic resonance imaging greater hemodynamic activation of the nucleus accumbens was found during active avoidance, wherea...