On the transience of egocentric working memory: evidence from testing the contribution of limbic brain regions.
Rats trained on a nonmatching-to-turn rule revealed that egocentric working memory is readily disrupted, hard to use, and transient. In Experiment 1, rats failed to acquire the rule in a plus-maze. Experiment 2 used 2 different plus-mazes to remove any intramaze cues. Task acquisition occurred only when rats could use direction cues (i.e., nonegocentric cues). In Experiments 3 and 4, a J maze was used to minimize the retention interval and eliminate handling rats within a trial. All rats acquired the nonmatching rule, although a 3-s retention delay severely impaired performance. Fornix lesions transiently disrupted performance of the J-maze task (Experiments 3 and 4), but neither fornix (Experiment 1) nor retrosplenial (Experiment 2) lesions impaired the plus-maze tasks.
Baird
A L
AL
School of Psychology, Cardiff University, Cardiff, United Kingdom.
Putter
J E
JE
Muir
J L
JL
Aggleton
J P
JP
D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal; D004193:Discrimination Learning / Q000502:physiology; D008032:Limbic System / Q000033:anatomy & histology / Q000293:injuries / Q000502:physiology*; D008297:Male; D018782:Maze Learning / Q000502:physiology; D008570:Memory, Short-Term / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D012153:Retention, Psychology; D013037:Spatial Behavior / Q000502:physiology*