Regularization in Short-Term Memory for Serial Order.

Previous research has shown that short-term memory for serial order can be influenced by background knowledge concerning regularities of sequential structure. Specifically, it has been shown that recall is superior for sequences that fit well with familiar sequencing constraints. The authors report a corresponding effect pertaining to serial recall errors. Undergraduate participants performed immediate serial recall on sequences of pseudowords generated on the basis of an artificial grammar. After extensive experience with this material, recall errors displayed a bias toward regularizing responses, response sequences more probable, with respect to the artificial grammar, than the originally presented stimulus sequence. This regularization effect squares well with recent trace redintegration and Bayesian models of serial recall, and appears to represent an analog of the schema-based error patterns observed in other domains of memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Serial Position Effects and the Picture-Superiority Effect in the Group Recall of Unshared Information.

This research examined how serial position effects (i.e., primacy and recency effects) and the picture-superiority effect (i.e., the tendency to recall pictures better than words) can impact the recall of unshared information (i.e., information known by only 1 group member). In 2 experiments, participants studied a stimulus list of pictures and words and completed a group recall task. In both experiments, the authors found that the primacy effect and the picture-superiority effect influenced how much unshared information was recalled and when it was recalled. However, there was little impact of the recency effect on either how much unshared information was recalled or when it was recalled. The implications of these findings for future theoretical research and applications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Anticipating by Pigeons Depends on Local Statistical Information in a Serial Response Time Task.

Pigeons responded in a serial response time task patterned after that of M. J. Nissen and P. Bullemer (1987) with humans. Experiment 1 produced global facilitation: Response times in repeating lists of locations were faster than when locations were random. Response time to a spatial location was also a function of both that location's 1st- and 2nd-order local predictability, in rough agreement with the Hick-Hyman law, according to which response time is a linear function of amount of information. Experiment 2 showed that both local and global facilitation is limited to moderate response-to-stimulus intervals of about 0.50 to 2.00 s. Experiment 3 showed that response time did not depend on global statistical information. Overall, local and global performances depended on local statistical information, but global performance did not depend on global information. Local facilitation was interpreted in plain English as anticipating. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

The Hippocampal Role in Spatial Memory and the Familiarity-Recollection Distinction: A Case Study.

Memory for object locations and for events (comprising the receipt of an object) was tested in a case of developmental amnesia with focal hippocampal damage ("Jon"; F. Vargha-Khadem et al., 1997). Tests used virtual reality environments and forced-choice recognition with foils chosen to equalize the performance of control participants across conditions. Memory for the objects received was unimpaired, but the context of their receipt was forgotten. Memory for short lists of object locations was unimpaired when tested from the same viewpoint as presentation but impaired when tested from a shifted viewpoint. Same-view performance was disrupted by changing the background scene. These results are consistent with Jon having preserved matching to fixed sensory-bound representations but impaired reconstructed or manipulable representations underlying shifted-viewpoint recognition and episodic recollection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An fMRI Study of Episodic Memory: Retrieval of Object, Spatial, and Temporal Information.

Sixteen participants viewed a videotaped tour of 4 houses that highlighted a series of objects and their spatial locations. Participants were tested for memory of object, spatial, and temporal-order information while undergoing functional magnetic resonance imaging. Preferential activation was observed in the right parahippocampal gyrus during the retrieval of spatial-location information. Retrieval of contextual information (spatial location and temporal order) was associated with activation in the right dorsolateral prefrontal cortex. In bilateral posterior parietal regions, greater activation was associated with processing of visual scenes regardless of the memory judgment. These findings support current theories positing roles for frontal and medial temporal regions during episodic retrieval and suggest a specific role for the hippocampal complex in the retrieval of spatial-location information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Order Information in Working Memory: An Integrative Review of Evidence From Brain and Behavior.

Evidence about memory for order information comes from a number of different methodologies: human cognition, patient studies, neuroimaging studies, and animal lesion and behavioral studies. The present article discusses (a) evidence that order and item memory are separable; (b) proposed mechanisms for order memory (interitem associations, direct codes, hierarchical codes, feature codes, and magnitude codes) and evidence for each; (c) evidence for the neural substrates of order memory from patient, neuroimaging, and animal lesion and single-cell recording studies; (d) barriers to integration between the disciplines; and (e) suggestions for better coordination of efforts between the different disciplines. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of Apolipoprotein E Genotype on Spatial Attention, Working Memory, and Their Interaction in Healthy, Middle-Aged Adults: Results From the National Institute of Mental Health's BIOCARD Study.

The cognitive consequences of the apolipoprotein E-ε4 (APOE-ε4) allele were examined in middle age, before likely onset of symptoms of Alzheimer's disease. The authors identified 3 cognitive processes--visuospatial attention, spatial working memory, and the effect of visuospatial attention on working memory--and devised "behavioral assays" of the integrity of components of these processes. Redirecting visuospatial attention, retention of memory for location, and attentional modulation of memory of target location were affected by APOE genotype. Visuospatial attention showed additive effects of ε4 gene dose; each additional ε4 allele inherited further slowed disengagement from invalidly cued space. In contrast, working memory performance was affected only in ε4 homozygotes. Effect sizes for the APOE gene were moderate to large, ranging from 14% to 24%. Effects of APOE genotype on component processes of cognition in healthy, middle-aged adults is consistent with the emergence in adulthood of an APOE-ε4 cognitive phenotype. (PsycINFO Database Record (c) 2010 APA, all rights reserved)