Biomaterial Database

Late post-learning participation of entorhinal cortex in memory processes. 1982

M Gauthier, and C Destrade, and B Soumireu-Mourat

Mice of the BALB/c strain were bilaterally implanted with electrodes in the lateral entorhinal cortex (EC) in order to study the influence of post-trial EC stimulation on memory. The learning task was a food reinforced operant conditioning. At one of several time intervals after a first learning session, the experimental groups were stimulated for 80 s with subseizure current intensity. Testing was carried out 24 h later. In the first experiment, a continuous reinforcement schedule was used. EC stimulation had no effect when applied at the 30-s or 3-h intervals, but surprisingly a 30-min delayed stimulation greatly improved retention compared to performance of non-stimulated animals. In the second experiment, the same paradigm was used in a discriminative operant conditioning task. The same facilitation on retention was observed only with the 30-min delayed stimulation. Compared to previous data with hippocampal or hypothalamic stimulation, the present results reveal that EC is lately involved in memory processes.

UI	MeSH Term	Description	Entries
D008032	Limbic System	A set of forebrain structures common to all mammals that is defined functionally and anatomically. It is implicated in the higher integration of visceral, olfactory, and somatic information as well as homeostatic responses including fundamental survival behaviors (feeding, mating, emotion). For most authors, it includes the AMYGDALA; EPITHALAMUS; GYRUS CINGULI; hippocampal formation (see HIPPOCAMPUS); HYPOTHALAMUS; PARAHIPPOCAMPAL GYRUS; SEPTAL NUCLEI; anterior nuclear group of thalamus, and portions of the basal ganglia. (Parent, Carpenter's Human Neuroanatomy, 9th ed, p744; NeuroNames, http://rprcsgi.rprc.washington.edu/neuronames/index.html (September 2, 1998)).	Limbic Systems,System, Limbic,Systems, Limbic
D008297	Male		Males
D008568	Memory	Complex mental function having four distinct phases: (1) memorizing or learning, (2) retention, (3) recall, and (4) recognition. Clinically, it is usually subdivided into immediate, recent, and remote memory.
D008807	Mice, Inbred BALB C	An inbred strain of mouse that is widely used in IMMUNOLOGY studies and cancer research.	BALB C Mice, Inbred,BALB C Mouse, Inbred,Inbred BALB C Mice,Inbred BALB C Mouse,Mice, BALB C,Mouse, BALB C,Mouse, Inbred BALB C,BALB C Mice,BALB C Mouse
D011939	Mental Recall	The process whereby a representation of past experience is elicited.	Recall, Mental
D012055	Reinforcement Schedule	A schedule prescribing when the subject is to be reinforced or rewarded in terms of temporal interval in psychological experiments. The schedule may be continuous or intermittent.	Reinforcement Schedules,Schedule, Reinforcement,Schedules, Reinforcement
D012153	Retention, Psychology	The persistence to perform a learned behavior (facts or experiences) after an interval has elapsed in which there has been no performance or practice of the behavior.	Psychological Retention,Retention (Psychology),Psychology Retention,Retention, Psychological
D003216	Conditioning, Operant	Learning situations in which the sequence responses of the subject are instrumental in producing reinforcement. When the correct response occurs, which involves the selection from among a repertoire of responses, the subject is immediately reinforced.	Instrumental Learning,Learning, Instrumental,Operant Conditioning,Conditionings, Operant,Instrumental Learnings,Learnings, Instrumental,Operant Conditionings
D004193	Discrimination Learning	Learning that is manifested in the ability to respond differentially to various stimuli.	Discriminative Learning,Discrimination Learnings,Discriminative Learnings,Learning, Discrimination,Learning, Discriminative
D004558	Electric Stimulation	Use of electric potential or currents to elicit biological responses.	Stimulation, Electric,Electrical Stimulation,Electric Stimulations,Electrical Stimulations,Stimulation, Electrical,Stimulations, Electric,Stimulations, Electrical