Memory For Spatial Information Research Articles

Effects of retention interval length on young and elderly adults' memory for spatial information

Adult age differences in spatial memory following retention intervals of various lengths were examined in 47 young and 56 elderly subjects who recalled spatial information following either a 3-, 15-, or 30-min retention interval. The elderly adults were significantly less accurate than the young adults following the 30-min retention interval only; there was no statistically significant effect of age at the 3-min and 15-min retention intervals. It is concluded that younger adults experience greater temporal stability of spatial memory than do older adults, and the relevance of the present findings for Craik's environmental support hypothesis is discussed.

Cholinergic blockade effects on spatial integration versus cue discrimination performance.

A within-subjects investigation was conducted to determine the effects of central versus peripheral cholinergic blockade in animals tested either on a spatial integration task in which the possibility of rule learning was also available or on a visual discrimination task in which the daily location of food was marked by a distinctive visual stimulus pattern. All testing was conducted on the Maier three-table apparatus. It was found that the only effect of the peripheral cholinergic blockade on the performance of either task group was to produce a decrease in exploratory behavior. In contrast, central cholinergic blockade markedly impaired spatial integration performance; however, it did not impair the ability of animals in rule learning or visual discrimination learning. It was also found that central cholinergic blockade impaired the animal's tendency to enter all tables before reentering a given table during the exploratory phase of the daily session. This finding was interpreted as reflecting an impairment of working memory for spatial information, rather than a general impairment in working memory, and this interpretation was applied to the explanation of the deficit in the spatial integration performance.

Item and order information in spatial memory.

Item and order information in spatial memory.

Memory for spatial information in young and old adults.

Memory for spatial information in young and old adults.

Memory for spatial information in young and old adults.

Memory for spatial information in young and old adults.

Time-dependent effects of ECS on spatial memory in rats

The effects of electroconvulsive shock (ECS) on working memory for spatial information were studied in rats trained in an eight-arm radial maze. ECS was administered at varying times during a 4- or 6-hr-long retention interval, imposed between the rat's fourth and fifth choices. ECS treatment 2 or 4 hr after choice 4 produced severe amnesia, but if the same ECS treatment was given within 15 min of choice 4, spatial memory was not affected. With the choice 4 ECS interval at 30 min, partial amnesia was observed. Analysis of the pattern of errors indicated that all of the errors made after ECS on the retention tests involved reentries into arms visited on choices 1–4. This duplicates the error pattern associated with “natural forgetting” (i.e., memory loss at very long retention intervals) and indicates that the amnesia following ECS was not the result of general confusion or failure to remember the win—shift strategy required by the task. Control tests showed that administering ECS 2 hr before choices 1–4 or delivering a painful footshock 2 hr after choice 4 did not degrade spatial memory. Thus the amnesic effects of ECS treatment during the retention interval do not appear to result from proactive influences on performance or the potentially disruptive effects of novel, stressful stimulation. Increasing the strength of the ECS did not lead to amnesia when ECS was given immediately after choice 4. These findings provide the first clear demonstration that rat spatial memory in the radial maze can be disrupted by a treatment administered during the retention interval. At the same time the data suggest that some forms of spatial memory in the rat are somewhat protected from assault by traumatic agents for several minutes after their formation.

The Representation of Spatial Information in Memory

Following memorisation of the spatial arrangement of an array of circles, subjects were asked to recall the circles in a type of free-recall task designed to determine the structure of the memorised information. Their performance showed that the circles tended to be recalled in an order that corresponded with a top-to-bottom ordering of circles on the array. In a second experiment the input order of the circles was varied by presenting them successively. The results indicated that input order influenced recall order. The implications for hypotheses about the structure and manipulation of stored spatial information were discussed.

Memory for descriptive and spatial information in complex pictures.

Memory for several kinds of information in complex pictures was studied. Stimuli were line drawings of either real-world scenes or unorganized collections of objects. Memory was tested by recognition and reconstruction tests, given immediately and/or after a week. Organization of the pictures had little effect on memory for size, orientation, or physical appearance of objects in the pictures. There was only a small loss of these types of descriptive information over a week's time. Organization of the pictures had a major effect on memory for location of objects in the pictures. Memory for location on the horizontal dimension declined markedly for both types of pictures over a week. Performance remained high on the vertical dimension for organized pictures, and systematic distortion occurred on this dimension for unorganized pictures. Reconstruction data were compared with the performance of subjects who had not seen the pictures before. It was concluded that real-world schemata do not affect encoding of some types of descriptive information, but play an important role in both encoding and memory for spatial information.