Ultra-short periods of wakeful rest promote the viewpoint-invariance of entities mnemonic representations

Humans can recognize thousands of visual objects after a single exposure, even against highly confusable objects, and despite viewpoint changes between learning and recognition. Memory consolidation processes like those taking place during wakeful rest contribute to such a feat, possibly by protecting the fine details of objects’ representations. However, whether rest-related consolidation promotes the viewpoint invariance of mnemonic representations for individual objects remains unexplored.Fifteen participants underwent a speeded visual recognition memory task tapping on familiarity-based recognition of individual objects, across four conditions manipulating post- encoding rest. Viewpoints of target items were modified between study and test while controlling study-test perceptual distance, and targets and lures shared the same subordinate category, making recognition independent from perceptual and conceptual fluency. Performance was very accurate, even without post-encoding rest, which did not enhance memory. However, rest uniquely made target detection immune to study-test perceptual distance.These findings suggest that very short periods of wakeful rest (down to 2-sec post-stimulus) suffice to achieve complete mnemonic viewpoint-invariance, pushing forward the strength of post-encoding rest in learning and memory. They also strongly argue for a holistic, viewpoint- invariant, mnemonic representation of visual objects.

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The presence of semantic content in a visual recognition memory task reduces the severity of neglect

Neuropsychologia ◽

10.1016/j.neuropsychologia.2021.107860 ◽

2021 ◽

Vol 157 ◽

pp. 107860

Author(s):

Elior Moreh ◽

Ehud Zohary ◽

Tanya Orlov

Keyword(s):

Recognition Memory ◽

Visual Recognition ◽

Memory Task ◽

Semantic Content ◽

Recognition Memory Task ◽

Visual Recognition Memory

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Mnemonic firing of neurons in the monkey temporal pole during a visual recognition memory task

Journal of Neurophysiology ◽

10.1152/jn.1995.74.1.162 ◽

1995 ◽

Vol 74 (1) ◽

pp. 162-178 ◽

Cited By ~ 90

Author(s):

K. Nakamura ◽

K. Kubota

Keyword(s):

Recognition Memory ◽

Visual Information ◽

Visual Recognition ◽

Discharge Rate ◽

Memory Task ◽

Delay Period ◽

Recognition Memory Task ◽

Visual Response ◽

Visual Recognition Memory ◽

Temporal Pole

1. We examined single-neuronal activity in the temporal pole of monkeys, including the anterior ventromedial temporal (VMT) cortex (the temporopolar cortex, area 36, area 35, and the entorhinal cortex) and the anterior inferotemporal (IT) cortex, during a visual recognition memory task. In the task, a trial began when the monkey pressed a lever. After a waiting period, a visual sample stimulus (S) was presented one to four times on a monitor with an interstimulus delay. Thereafter, a new stimulus (R) was presented. The monkeys were trained to remember S during the delay period and to release the lever in response to R. Colored photographs of natural objects were used as visual stimuli. 2. About 70% of the recorded neurons (225 of 311) responded to at least one of the Ss tested. Thirty percent of these neurons (68 of 225) continued to fire during the subsequent delay periods. In 75% of these neurons (51 of 68), the firing during the delay period strongly correlated with the response to S. 3. The discharge rate during the delay period did not correlate with the monkey's eye movements, pressing or releasing of the lever, or the reaction time. 4. If the monkey erroneously released the lever in response to S or during the delay period, the firing disappeared after the erroneous lever release. If the monkey failed to release the lever in response to R, the firing persisted even after R was withdrawn. The discharge rate in incorrect trials was comparable with that in correct trials. The neurons were considered to fire for as long as the memory of S was necessary. 5. Firing persisted even when an achromatic version or half (even a portion) of S was presented, indicating that the color, a particular portion, or the entire shape of S was not always necessary to elicit firing. 6. An S that elicited firing during the delay period invariably elicited a visual response. Neurons that fired during the delay period showed a higher stimulus selectivity than other visually responsive neurons in the anterior VMT cortex. Thus neurons that fire during the delay period represent a subgroup of visually responsive neurons that are selectively tuned to a certain stimulus. 7. More neurons fired during the delay period in the anterior VMT cortex than in the anterior IT cortex. 8. We conclude that firing during the delay period by neurons in the temporal pole reflects the short-term storage of visual information regarding a particular S.

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A Fast Visual Recognition Memory System in Humans Identified Using Intracerebral ERP

Cerebral Cortex ◽

10.1093/cercor/bhz287 ◽

2019 ◽

Vol 30 (5) ◽

pp. 2961-2971 ◽

Cited By ~ 1

Author(s):

Elodie Despouy ◽

Jonathan Curot ◽

Martin Deudon ◽

Ludovic Gardy ◽

Marie Denuelle ◽

...

Keyword(s):

Recognition Memory ◽

Medial Temporal Lobe ◽

Visual Recognition ◽

Critical Role ◽

Memory Task ◽

Reaction Times ◽

Memory System ◽

Event Related Potential ◽

Visual Recognition Memory ◽

Fast Recognition

Abstract One key item of information retrieved when surveying our visual world is whether or not objects are familiar. However, there is no consensus on the respective roles of medial temporal lobe structures, particularly the perirhinal cortex (PRC) and hippocampus. We considered whether the PRC could support a fast recognition memory system independently from the hippocampus. We recorded the intracerebral electroencephalograph activity of epileptic patients while they were performing a fast visual recognition memory task, constraining them to use their quickest strategy. We performed event-related potential (ERP) and classification analyses. The PRC was, by far, the earliest region involved in recognition memory. This activity occurred before the first behavioral responses and was found to be related to reaction times, unlike the hippocampus. Single-trial analyses showed that decoding power was equivalent in the PRC and hippocampus but occurred much earlier in the PRC. A critical finding was that recognition memory-related activity occurred in different frontal and parietal regions, including the supplementary motor area, before the hippocampus. These results, based on ERP analyses, suggest that the human brain is equipped with a fast recognition memory system, which may bypass the hippocampus and in which the PRC plays a critical role.

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Mapping the Visual Recognition Memory Network with PET in the Behaving Baboon

Journal of Cerebral Blood Flow & Metabolism ◽

10.1097/00004647-200002000-00001 ◽

2000 ◽

Vol 20 (2) ◽

pp. 213-219 ◽

Cited By ~ 23

Author(s):

Xavier Blaizot ◽

Brigitte Landeau ◽

Jean-Claude Baron ◽

Chantal Chavoix

Keyword(s):

Recognition Memory ◽

Large Scale ◽

Visual Recognition ◽

Memory Task ◽

Magnetic Resonance Images ◽

Nucleus Basalis ◽

Healthy Humans ◽

Visual Recognition Memory ◽

Memory Network ◽

First Time

By means of a novel 18F-fluoro-deoxyglucose PET method designed for cognitive activation imaging in the baboon, the large-scale neural network involved in visual recognition memory in the nonhuman primate was mapped for the first time. In this method, the tracer is injected in the awake, unanesthetized, and unrestrained baboon performing the memory task, and brain imaging is performed later under light anesthesia. Brain maps obtained during a computerized trial-unique delayed matching-to-sample task (lists of meaningless geometrical patterns and delay > 9 seconds) were statistically compared pixel-by-pixel to maps obtained during a specially designed visuomotor control task. When displayed onto the baboon's own anatomic magnetic resonance images, foci of significant activation were distributed along the ventral occipitotemporal pathway, the inferomedial temporal lobe (especially the perirhinal cortex and posterior hippocampal region), and the orbitofrontal cortex, consistent with lesion, single-unit, and autoradiographic studies in monkeys, as well as with activation studies in healthy humans. Additional activated regions included the nucleus basalis of Meynert, the globus pallidus and the putamen. The results also document an unexpected left-sided advantage, suggesting hemispheric functional specialization for recognition of figural material in nonhuman primates.

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