PubMed HealthSearch

PubMed · 2737866

Avoidance conditioning in amnesia: a single case experimental study.

Abstract

We present a single case study of avoidance conditioning in a seriously amnesic patient with bilateral ischemic lesions of the brain. A four-path maze was used for conditioning. The procedure consisted in an aversive stimulus that the patient received every time he traced one of the four maze-paths connected to an electric shock generator with a stylus. Using a single case experimental design A-B-A, we found that the patient learned to avoid the path connected to the electric shock, although he never showed awareness of this. Our study confirms once again that conditioning is one of the residual learning capabilities in amnesic patients. Different neural systems are probably involved in conditioning processes.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

C Blundo, C Ricci. 1989. Avoidance conditioning in amnesia: a single case experimental study.. https://doi.org/10.1007/bf02333618

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Implicit knowledge: new perspectives on unconscious processes.

Recent evidence from cognitive science and neuroscience indicates that brain-damaged patients and normal subjects can exhibit nonconscious or implicit knowledge of stimuli that they fail to recollect consciously or perceive explicitly. Dissociations between implicit and explicit knowledge, which have been observed across a variety of domains, tasks, and materials, raise fundamental questions about the nature of perception, memory, and consciousness. This article provides a selective review of relevant evidence and considers such phenomena as priming and implicit memory in amnesic patients and normal subjects, perception without awareness and "blindsight" in patients with damage to visual cortex, and nonconscious recognition of familiar faces in patients with facial-recognition deficits (prosopagnosia). A variety of theoretical approaches to implicit/explicit dissociations are considered. One view is that all of the various dissociations can be attributed to disruption or disconnection of a common mechanism underlying conscious experience; an alternative possibility is that each dissociation requires a separate explanation in terms of domain-specific processes and systems. More generally, it is concluded that rather than reflecting the operation of affectively charged unconscious processes of the kind invoked by psychodynamic or Freudian theorists, dissociations between implicit and explicit knowledge are a natural consequence of the ordinary computations of the brain.

Amnesia

D-cycloserine, a modulator of the N-methyl-D-aspartate receptor, improves spatial learning in rats treated with muscarinic antagonist.

The results of the present study indicate that D-cycloserine, a partial agonist at the glycine binding site, which is a positive modulation site of the N-methyl-D-aspartate receptor, could improve dose dependently the acquisition of a water maze task in rats treated with scopolamine, a muscarinic antagonist. The low to moderate doses of D-cycloserine which improved learning did not affect swimming speed in scopolamine-treated rats. The higher dose did not improve learning, but it increased swimming speed in scopolamine-treated rats. These results show a dissociation between impaired acquisition and abnormal behavioral activity in scopolamine-treated rats in the water maze task. Furthermore, the present results suggest that D-cycloserine can act as a cognitive enhancer at the appropriate doses.

Amnesia

The selective protein kinase C inhibitor, NPC 15437, induces specific deficits in memory retention in mice.

We studied the effects of a selective inhibitor of protein kinase C (PKC), 2,6-diamino-N-[(1-(1-oxotridecyl)-2-piperidinyl]methyl)hexamide (NPC 15437), on acquisition and memory retention of a Y-maze avoidance task in mice. Post-training administration of NPC 15437 (0.1-10 mg/kg i.p.) induced a dose-dependent deficit in retention of the temporal but not the spatial component of the task. This selective amnesia does not reflect state dependence and NPC 15437 (1 mg/kg) had no effect on acquisition and memory retrieval. Our results suggest that this new PKC inhibitor interferes with mechanisms underlying memory consolidation. This is in agreement with recent findings suggesting that PKC is involved in memory processes.

Amnesia