Five dogs were preliminarily trained in the situation of classical defensive conditioned reflexes. The training sharply impeded the subsequent instrumental avoidance conditioning (with the stimulus applied to one leg and the avoidance movement accomplished by another leg). However, following the elaboration of the instrumental avoidance to one of the signals previously used in the classical sit...

Drug motivation models postulate that attention biasing toward smoking-related cues is a cognitive mechanism supporting continued or renewed drug use, and they predict that drug use history, deprivation, and distress should modulate the extent of this bias. The present study used the modified Stroop paradigm to extend past research regarding attention biasing toward smoking and unpleasant, plea...

We examined the local field potential of the hippocampus to monitor brain states during a conditional discrimination task, in order to elucidate the relationship between ongoing brain states and a conditioned motor reflex. Five 10-week-old Wistar/ST male rats underwent a serial feature positive conditional discrimination task in eyeblink conditioning using a preceding light stimulus as a condit...

The purpose of this study was to determine the effect of trait anxiety and stressor intensity on arousal and motor performance during a pinch task. We examined the steadiness of a precision task in the presence and absence of an imposed stressor on subjects with moderate and low trait anxiety. Subjects with the 26 highest and 14 lowest anxiety scores were assigned to one of three groups: a cont...

Studies of the neural mechanisms of learning, especially of sensitization, have benefitted from extensive research on the model species, Aplysia californica (hereafter Aplysia). Considering this volume of literature on mechanisms, it is surprising that our understanding of the ecological context of sensitization in Aplysia is completely lacking. Indeed, the widespread use of strong electric sho...

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...

Lhermitte's sign (LS) or 'Baber's chair sign' consists of a sudden electric shock-like sensation that shoots down the back and into the limbs when the neck is flexed. In patients with cancer, LS has been associated with spinal cord involvement, postirradiation phenomenon, and chemotherapy:

Single neuronal activities of 93 units from CA3 region of hippocampus were studied in unanaesthetised mobile rabbits. Effects of repeated reinforced conditioned stimuli (CS+) were observed on these neuronal firing pattern. The conditioned stimuli (CS) consisted of a tone 600 Hz for 6 seconds which was reinforced by a subcutaneous electrical shock (0.4 V, frequency 250 sec, and pulse width 300 m...

Reactivation of an already consolidated memory makes it labile for a period of several hrs, which are required for its reconsolidation. Evidence suggests that the return of conditioned fear through spontaneous recovery, reinstatement, or renewal can be prevented by blockading this reconsolidation process using pharmacological or behavioral interventions. Postretrieval-extinction learning has be...