Neural overlap in item representations across episodes impairs context memory

AbstractWe frequently encounter the same item in different contexts, and when that happens, memories of earlier encounters can get reactivated in the brain. Here we examined how these existing memories are changed as a result of such reactivation. We hypothesized that when an item’s initial and subsequent neural representations overlap, this allows the initial item to become associated with novel contextual information, interfering with later retrieval of the initial context. That is, we predicted a negative relationship between representational similarity across repeated experiences of an item and subsequent source memory for the initial context. We tested this hypothesis in an fMRI study, in which objects were presented multiple times during different tasks. We measured the similarity of the neural patterns in lateral occipital cortex that were elicited by the first and second presentations of objects, and related this neural overlap score to source memory in a subsequent test. Consistent with our hypothesis, greater item-specific pattern similarity was linked to worse source memory for the initial task. Our findings suggest that the influence of novel experiences on an existing context memory depends on how reliably a shared component (i.e., same item) is represented across these episodes.

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Patients with Schizophrenia Remember that an Event has Occurred, but not When

The British Journal of Psychiatry ◽

10.1192/bjp.168.4.427 ◽

1996 ◽

Vol 168 (4) ◽

pp. 427-431 ◽

Cited By ~ 67

Author(s):

Lydia Rizzo ◽

Jean-Marie Danion ◽

Martial Van Der Linden ◽

Danielle Grangé

Keyword(s):

Memory Impairment ◽

Discrimination Task ◽

Contextual Information ◽

Normal Subjects ◽

Memory Deficit ◽

Temporal Context ◽

Context Memory

BackgroundThe context memory deficit hypothesis of schizophrenia postulates that the long-term deficit associated with this disorder is related to a memory impairment for contextual information.MethodTo test this hypothesis, memory for temporal context was assessed in 33 patients with schizophrenia and 33 normal subjects, using a recency discrimination task.ResultsWhereas patients were able to recall and recognise target items, they were unable to recognise from among the target items those which had been most recently learned.ConclusionsSchizophrenia is associated with a temporal context memory deficit.

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Managing Social Distance in Geographically Distributed Teams

Handbook of Research on Remote Work and Worker Well-Being in the Post-COVID-19 Era - Advances in Human Resources Management and Organizational Development ◽

10.4018/978-1-7998-6754-8.ch016 ◽

2021 ◽

pp. 286-307

Author(s):

Vinita Seshadri ◽

Elangovan N.

Keyword(s):

Social Distance ◽

Team Effectiveness ◽

Contextual Information ◽

Negative Relationship ◽

Distributed Teams ◽

Team Members ◽

Shared Identity ◽

The Social ◽

Distributed Team ◽

Geographically Distributed

The chapter highlights the social distance, i.e. lack of emotional connection, formed among individuals working remotely in a geographically distributed team. The virtuality and cultural diversity of such teams creates limited opportunities for dispersed members to build social ties with remote team members leading to formation of ‘us' versus ‘them' attitudes which corrode team effectiveness. Based on a survey of 482 Indian IT professionals working in distributed teams, we find that social distance negatively impacts team effectiveness. Further, the results of the study show that practices such as task interdependence, inclusive communication, contextual information and shared identity can moderate the negative relationship between social distance and team effectiveness at varying levels of perceived status equality among individuals working in geographically distributed teams. The chapter provides recommendations for the effective management of geographically distributed teams whereby managers act as a bridge between the team members to overcome social distance.

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Overlap between the Neural Correlates of Cued Recall and Source Memory: Evidence for a Generic Recollection Network?

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00202 ◽

2012 ◽

Vol 24 (5) ◽

pp. 1127-1137 ◽

Cited By ~ 51

Author(s):

Hiroki R. Hayama ◽

Kaia L. Vilberg ◽

Michael D. Rugg

Keyword(s):

Source Memory ◽

Cued Recall ◽

Study Item ◽

Subsequent Test ◽

Parahippocampal Cortex ◽

Form Part ◽

To Come ◽

Cortical Regions ◽

Successful Recall ◽

Source Retrieval

Recall of a studied item and retrieval of its encoding context (source memory) both depend on recollection of qualitative information about the study episode. This study investigated whether recall and source memory engage overlapping neural regions. Participants (n = 18) studied a series of words, which were presented either to the left or right of fixation. fMRI data were collected during a subsequent test phase in which three-letter word-stems were presented, two thirds of which could be completed by a study item. Instructions were to use each stem as a cue to recall a studied word and, when recall was successful, to indicate the word's study location. When recall failed, the stem was to be completed with the first word to come to mind. Relative to stems for which recall failed, word-stems eliciting successful recall were associated with enhanced activity in a variety of cortical regions, including bilateral parietal, posterior midline, and parahippocampal cortex. Activity in these regions was enhanced when recall was accompanied by successful rather than unsuccessful source retrieval. It is proposed that the regions form part of a “recollection network” in which activity is graded according to the amount of information retrieved about a study episode.

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Aging, Culture, and Memory for Socially Meaningful Item-Context Associations: An East-West Cross-Cultural Comparison Study

10.32920/14638179 ◽

2021 ◽

Author(s):

Lixia Yang ◽

Juan Li ◽

Julia Spaniol ◽

Lynn Hasher ◽

Andrea J. Wilkinson ◽

...

Keyword(s):

Independent Living ◽

Daily Life ◽

Contextual Information ◽

Cross Cultural ◽

Cultural Comparison ◽

Comparison Study ◽

Cross Cultural Comparison ◽

Age Related ◽

East West ◽

Context Memory

Research suggests that people in Eastern interdependent cultures process information more holistically and attend more to contextual information than do people in Western independent cultures. The current study examined the effects of culture and age on memory for socially meaningful item-context associations in 71 Canadians of Western European descent (35 young and 36 older) and 72 native Chinese citizens (36 young and 36 older). All participants completed two blocks of context memory tasks. During encoding, participants rated pictures of familiar objects. In one block, objects were rated either for their meaningfulness in the independent living context or their typicality in daily life. In the other block, objects were rated for their meaningfulness in the context of fostering relationships with others or for their typicality in daily life. The encoding in each block was followed by a recognition test in which participants identified pictures and their associated contexts. The results showed that Chinese outperformed Canadians in context memory, though both culture groups showed similar age-related deficits in item and context memory. The results suggest that Chinese are at an advantage in memory for socially meaningful item-context associations, an advantage that continues from young adulthood into old age.

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Neural decoding dissociates perceptual grouping between proximity and similarity in visual perception

10.1101/2021.11.15.468580 ◽

2021 ◽

Author(s):

Lin Hua ◽

Fei Gao ◽

Chantat Leong ◽

Zhen Yuan

Keyword(s):

Perceptual Grouping ◽

Time Windows ◽

Visual Stimuli ◽

Occipital Cortex ◽

Specific Pattern ◽

Response Patterns ◽

Cognitive Integration ◽

Brain Response ◽

Time Resolved ◽

Visual Element

Previous research on perceptual grouping primarily focused on the dynamics of single grouping principle in light of the Gestalt psychology. Yet, there has been comparatively little emphasis on the dissociation across two or more grouping principles. To tackle this issue, the current study aims at investigating how, when, and where the processing of two grouping principles (proximity and similarity) are established in the human brain by using a dimotif lattice paradigm and adjusting the strength of one grouping principle. Specifically, we measured the modulated strength of the other grouping principle, thus forming six visual stimuli. The current psychophysical results showed that similarity grouping effect was enhanced with reduced proximity effect when the grouping cues of proximity and similarity were presented simultaneously. Meanwhile, electrophysiological (EEG) response patterns were able to decode the specific pattern out of the six visual stimuli involving both principles in each trail by using time-resolved multivariate pattern analysis (MVPA). The onsets of the dissociation between the two grouping principles coincided within three time windows: the earliest proximity-defined local visual element arrangement in the middle occipital cortex, the middle-stage processing for feature selection modulating low-level visual cortex in the inferior occipital cortex and fusiform cortex, and the higher-level cognitive integration to make decisions for specific grouping preference in the parietal areas. In addition, brain responses were highly correlated with behavioral grouping. The results therefore provide direct evidence for a link between human perceptual space of grouping decision-making and neural space of these brain response patterns.

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Context-dependent decision making in a premotor circuit

10.1101/757104 ◽

2019 ◽

Cited By ~ 2

Author(s):

Zheng Wu ◽

Ashok Litwin-Kumar ◽

Philip Shamash ◽

Alexei Taylor ◽

Richard Axel ◽

...

Keyword(s):

Pyramidal Neurons ◽

Contextual Information ◽

Sensory Information ◽

Behavioral Responses ◽

Association Cortex ◽

Match To Sample ◽

Subsequent Test ◽

Layer 2 ◽

Test Odor ◽

Context Dependent

SummaryCognitive capacities afford contingent associations between sensory information and behavioral responses. We studied this problem using an olfactory delayed match to sample task whereby a sample odor specifies the association between a subsequent test odor and rewarding action. Multi-neuron recordings revealed representations of the sample and test odors in olfactory sensory and association cortex, which were sufficient to identify the test odor as match/non-match. Yet, inactivation of a downstream premotor area (ALM), but not orbitofrontal cortex, confined to the epoch preceding the test odor, led to gross impairment. Olfactory decisions that were not context dependent were unimpaired. Therefore, ALM may not receive the outcome of a match/non-match decision from upstream areas but contextual information—the identity of the sample—to establish the mapping between test odor and action. A novel population of pyramidal neurons in ALM layer 2 may mediate this process.

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Neural Correlates of Value-Driven Spatial Attention

10.1101/2021.06.28.450234 ◽

2021 ◽

Author(s):

Ming-Ray Liao ◽

Andy Jeesu Kim ◽

Brian A Anderson

Keyword(s):

Spatial Attention ◽

Spatial Information ◽

Occipital Cortex ◽

Brain Regions ◽

Test Phase ◽

Parahippocampal Gyrus ◽

Frontal Eye Field ◽

Subsequent Test ◽

Spatial Orienting ◽

Feature Based

Reward learning has been shown to habitually guide spatial attention to regions of a scene. However, the neural mechanisms that support this bias in spatial orienting are unknown. In the present study, participants learned to orient to a particular quadrant of a scene (high-value quadrant) to maximize monetary gains. This learning was scene-specific, with the high-value quadrant varying across different scenes. During a subsequent test phase, participants were faster at identifying a target if it appeared in the high-value quadrant (valid), and initial saccades were more likely to be made to the high-value quadrant. fMRI analyses during the test phase revealed learning-dependent priority signals in the bilateral caudate tail and superior colliculus, frontal eye field, substantia nigra, and insula, paralleling findings concerning feature-based value-driven attention. In addition, ventral regions typically associated with scene selective and spatial information processing, including the hippocampus, parahippocampal gyrus, and temporo-occipital cortex, were also implicated. Taken together, our findings offer new insights into the neural architecture subserving value-driven attention, both extending our understanding of nodes in the attention network previously implicated in feature-based value-driven attention and identifying a ventral network of brain regions implicated in rewards influence on scene-dependent spatial orienting.

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Delay-dependent contributions of medial temporal lobe regions to episodic memory retrieval

eLife ◽

10.7554/elife.05025 ◽

2015 ◽

Vol 4 ◽

Cited By ~ 50

Author(s):

Maureen Ritchey ◽

Maria E Montchal ◽

Andrew P Yonelinas ◽

Charan Ranganath

Keyword(s):

Episodic Memory ◽

Medial Temporal Lobe ◽

Functional Neuroimaging ◽

Contextual Information ◽

Medial Temporal Lobes ◽

Temporal Lobes ◽

Pattern Similarity ◽

Delayed Recognition ◽

Delay Dependent ◽

Over Time

The medial temporal lobes play an important role in episodic memory, but over time, hippocampal contributions to retrieval may be diminished. However, it is unclear whether such changes are related to the ability to retrieve contextual information, and whether they are common across all medial temporal regions. Here, we used functional neuroimaging to compare neural responses during immediate and delayed recognition. Results showed that recollection-related activity in the posterior hippocampus declined after a 1-day delay. In contrast, activity was relatively stable in the anterior hippocampus and in neocortical areas. Multi-voxel pattern similarity analyses also revealed that anterior hippocampal patterns contained information about context during item recognition, and after a delay, context coding in this region was related to successful retention of context information. Together, these findings suggest that the anterior and posterior hippocampus have different contributions to memory over time and that neurobiological models of memory must account for these differences.

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Fewer Constraints Enhance the Generation Effect for Source Memory in Younger, but not Older Adults

Open Psychology ◽

10.1515/psych-2018-0012 ◽

2019 ◽

Vol 1 (1) ◽

pp. 168-184 ◽

Cited By ~ 6

Author(s):

Matthew P. McCurdy ◽

Ryan C. Leach ◽

Eric D. Leshikar

Keyword(s):

Older Adults ◽

Associative Memory ◽

Source Memory ◽

Age Groups ◽

Generation Effect ◽

Relational Processing ◽

Generation Task ◽

Younger Adults ◽

Constraint Generation ◽

Context Memory

AbstractThe generation effect is the memory benefit for information that is self-generated compared to read. This effect is robust for both younger and older adults. Recent work with younger adults has shown that the generation effect for context memory (i.e., contextual details associated with an episode) can be increased when there are fewer rather than greater experimental constraints placed on what participants can generate. This increase in context memory is attributable to enhanced relational processing. Given older adults’ deficits in context memory the present study tested whether fewer generation constraints would similarly improve the generation effect for contextual details in older adults. In this study, we examined age differences in item and context (i.e., source and associative) memory across three different tasks comprising the encoding of cue-target pairs: a lower-constraint generation task (i.e., free response to cue, such as assist – ____), a higher-constraint generation task (i.e., solving an anagram, such as assist – hlpe), and a read task (i.e., simply reading the cue-target pair, such as assist – help). Both age groups showed improved item and context memory for materials studied during the generation tasks (both lower- and higher-constraint) compared to the read task. However, only younger adults showed increased source memory for lower-constraint compared to higher-constraint generation, whereas older adults showed equivalent source and associative memory for both lower- and higher-constraint generation tasks. These findings suggest both age groups benefit from self-generation, but older adults may benefit less from conditions that enhance relational processing (lower-constraint generation) in younger adults.

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