Neuronal correlate of pictorial short-term memory in the primate temporal cortexYasushi Miyashita

Miyashita, Yasushi; Chang, Han Soo

doi:10.1038/331068a0

Cited by 862 publications

(441 citation statements)

References 22 publications

Supporting

Mentioning

413

Contrasting

Order By: Relevance

“…There is recent neurophysiological evidence that pictorial short-term memory is represented by neural activity in cortical areas concerned with visual processing rather than in a specialized memory area from both single-unit studies on behaving monkeys (Miyashita & Chang, 1988) and regional blood-flow studies on man (Roland, 1989). Such findings add credibility to the general hypothesis of a close connection between perceptual discrimination and the mechanism of visual short-term memory.…”

Section: Discussionmentioning

confidence: 99%

Stimulus-specific mechanisms of visual short-term memory

et al. 1991

View full text Add to dashboard Cite

Abstract-The retention of spatial information in visual short-term memory was assessed by measuring spatial frequency discrimination thresholds with a two-interval forced-choice task varying the time interval between the two gratings to be compared. The memory of spatial frequency information was perfect across IO-see interstimulus intervals. Presentation of a "memory masker" grating during the interstimulus interval may interfere with short-term memory. This interference depends on the relative spatial frquency of the test and masker gratings, with maximum interference at spatial frequency differences of l-l.5 octaves and beyond. This range of interference with short-term memory is comparable to the bandwidth of sensory masking or adaptation. A change of the relative orientation of test and masker gratings does not produce interference with spatial frequency discrimination thresholds. These results suggest stimulus-specific interactions at higher-level representations of visual form.

show abstract

Section: Discussionmentioning

confidence: 99%

Stimulus-specific mechanisms of visual short-term memory

et al. 1991

View full text Add to dashboard Cite

show abstract

“…As mentioned above, for trained images the accepted physiological correlate and explanatory paradigm has been reverberating, selective neural delay activity [working memory (Miyashita, 1988;Miyashita and Chang, 1988;Sakai and Miyashita, 1991;Amit and Brunel, 1997;Camperi and Wang, 1998)]. However, this option is not available for novel images.…”

Section: Network Model (Theory)mentioning

confidence: 99%

Universal Memory Mechanism for Familiarity Recognition and Identification

Yakovlev¹,

Amit²,

Romani³

et al. 2008

J. Neurosci.

View full text Add to dashboard Cite

Macaque monkeys were tested on a delayed-match-to-multiple-sample task, with either a limited set of well trained images (in randomized sequence) or with never-before-seen images. They performed much better with novel images. False positives were mostly limited to catch-trial image repetitions from the preceding trial. This result implies extremely effective one-shot learning, resembling Standing's finding that people detect familiarity for 10,000 once-seen pictures (with 80% accuracy) (Standing, 1973). Familiarity memory may differ essentially from identification, which embeds and generates contextual information. When encountering another person, we can say immediately whether his or her face is familiar. However, it may be difficult for us to identify the same person. To accompany the psychophysical findings, we present a generic neural network model reproducing these behaviors, based on the same conservative Hebbian synaptic plasticity that generates delay activity identification memory. Familiarity becomes the first step toward establishing identification. Adding an inter-trial reset mechanism limits false positives for previous-trial images. The model, unlike previous proposals, relates repetition-recognition with enhanced neural activity, as recently observed experimentally in 92% of differential cells in prefrontal cortex, an area directly involved in familiarity recognition. There may be an essential functional difference between enhanced responses to novel versus to familiar images: The maximal signal from temporal cortex is for novel stimuli, facilitating additional sensory processing of newly acquired stimuli. The maximal signal for familiar stimuli arising in prefrontal cortex facilitates the formation of selective delay activity, as well as additional consolidation of the memory of the image in an upstream cortical module.

show abstract

“…This task requires a relatively simple form of working memory, where the prior stimulus must be maintained over a delay until the next stimulus appears, so that the subject can discriminate the target from non-target sequences. This is the kind of activationbased working memory that has often been observed for example in electrophysiological studies of working memory in monkeys (e.g., Fuster & Alexander, 1971;Kubota & Niki, 1971;Miyashita & Chang, 1988;Funahashi, Bruce, & Goldman-Rakic, 1989;Miller, Erickson, & Desimone, 1996).…”

Section: The Pbwm Model Of Working Memorymentioning

confidence: 99%

Banishing the homunculus: Making working memory work

2006

View full text Add to dashboard Cite

Abstract:The prefrontal cortex (PFC) has long been thought to subserve both working memory and "executive" function, but the mechanistic basis of their integrated function has remained poorly understood, often amounting to a homunculus. This paper reviews the progress in our lab and others pursuing a long-term research agenda to deconstruct this homunculus by elucidating the precise computational and neural mechanisms underlying these phenomena. We outline six key functional demands underlying working memory, and then describe the current state of our computational model of the PFC and associated systems in the basal ganglia (BG). The model, called PBWM (prefrontal-cortex, basal-ganglia working memory model), relies on actively maintained representations in the PFC, which are dynamically updated/gated by the BG. It is capable of developing human-like performance largely on its own by taking advantage of powerful reinforcement learning mechanisms, based on the midbrain dopaminergic system and its activation via the BG and amygdala. These learning mechanisms enable the model to learn to control both itself and other brain areas in a strategic, task-appropriate manner. The model can learn challenging working memory tasks, and has been corroborated by several important empirical studies.

show abstract

Neuronal correlate of pictorial short-term memory in the primate temporal cortexYasushi Miyashita

Cited by 862 publications

References 22 publications

Stimulus-specific mechanisms of visual short-term memory

Stimulus-specific mechanisms of visual short-term memory

Universal Memory Mechanism for Familiarity Recognition and Identification

Banishing the homunculus: Making working memory work

Contact Info

Product

Resources

About