Action boosts episodic memory encoding in humans via engagement of a noradrenergic system

SUMMARYWe are constantly interacting with our environment whilst we encode memories. However, how actions influence memory formation remains poorly understood. Goal-directed movement engages the locus coeruleus (LC), the main source of noradrenaline in the brain. Noradrenaline is also known to enhance episodic encoding, suggesting that action could improve memory via LC engagement. Here we demonstrate, across seven experiments, that action (Go-response) enhances episodic encoding for stimuli unrelated to the action itself, compared to action inhibition (NoGo). Supporting a noradrenergic mechanism underlying this enhancement, functional magnetic resonance imaging, and pupil diameter as a proxy measure for LC-noradrenaline transmission, indicate increased encoding-related LC activity during action. A final experiment confirmed a novel prediction derived from these data that emotionally aversive stimuli, which recruit the noradrenergic system, modulate the mnemonic advantage conferred by Go-responses relative to neutral stimuli. We therefore provide converging evidence that action boosts episodic memory encoding via a noradrenergic mechanism.

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Cooperation between the Hippocampus and the Striatum during Episodic Encoding

Journal of Cognitive Neuroscience ◽

10.1162/jocn.2010.21549 ◽

2011 ◽

Vol 23 (7) ◽

pp. 1597-1608 ◽

Cited By ~ 60

Author(s):

Talya Sadeh ◽

Daphna Shohamy ◽

Dana Rubi Levy ◽

Niv Reggev ◽

Anat Maril

Keyword(s):

Episodic Memory ◽

Learning And Memory ◽

Cooperative Interaction ◽

Memory Encoding ◽

Functional Magnetic Resonance ◽

Resonance Imaging ◽

System A ◽

Episodic Encoding ◽

Within Subjects

The hippocampus and the striatum are thought to play distinct roles in learning and memory, each supporting an independent memory system. A fundamental question is whether, and how, these systems interact to jointly contribute to learning and memory. In particular, it remains unknown whether the striatum contributes selectively to implicit, habitual learning, or whether the striatum may also contribute to long-term episodic memory. Here, we show with functional magnetic resonance imaging (fMRI) that the hippocampus and the striatum interact cooperatively to support episodic memory formation. Participants were scanned during a memory encoding paradigm and, subsequently, were tested for memory of encoded items. fMRI data revealed that successful memory was associated with greater activity in both the hippocampus and the striatum (putamen) during encoding. Furthermore, activity in the hippocampus and the striatum was correlated within subjects for items that were later remembered, but not for items that were forgotten. Finally, across subjects, the strength of the correlation between the hippocampus and the striatum predicted memory success. These findings provide novel evidence for contributions of both the striatum and the hippocampus to successful episodic encoding and for a cooperative interaction between them.

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Episodic memory-related activation in schizophrenia: meta-analysis

The British Journal of Psychiatry ◽

10.1192/bjp.187.6.500 ◽

2005 ◽

Vol 187 (6) ◽

pp. 500-509 ◽

Cited By ~ 143

Author(s):

Amélie M. Achim ◽

Martin Lepage

Keyword(s):

Episodic Memory ◽

Temporal Lobe ◽

Medial Temporal Lobe ◽

Meta Analysis ◽

Temporal Cortex ◽

Neural Correlates ◽

Brain Regions ◽

Group Differences ◽

Memory Encoding ◽

The Brain

BackgroundNumerous studies have examined the neural correlates of episodic memory deficits in schizophrenia, yielding both consistencies and discrepancies in the reported patterns of results.AimsTo identify in schizophrenia the brain regions in which activity is consistently abnormal across imaging studies of memory.MethodData from 18 studies meeting the inclusion criteria were combined using a recently developed quantitative meta-analytic approach.ResultsRegions of consistent differential activation between groups were observed in the left inferior prefrontal cortex, medial temporal cortex bilaterally, left cerebellum, and in other prefrontal and temporal lobe regions. Subsequent analyses explored memory encoding and retrieval separately and identified between-group differences in specific prefrontal and medial temporal lobe regions.ConclusionsBeneath the apparent heterogeneity of published findings on schizophrenia and memory, a consistent and robust pattern of group differences is observed as a function of memory processes.

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Statistical prediction of the future impairs episodic encoding of the present

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2013291117 ◽

2020 ◽

Vol 117 (37) ◽

pp. 22760-22770 ◽

Cited By ~ 4

Author(s):

Brynn E. Sherman ◽

Nicholas B. Turk-Browne

Keyword(s):

Episodic Memory ◽

Predictive Model ◽

Statistical Learning ◽

Statistical Prediction ◽

Behavioral Tests ◽

The Past ◽

The Future ◽

Episodic Encoding ◽

Past Experiences ◽

The Brain

Memory is typically thought of as enabling reminiscence about past experiences. However, memory also informs and guides processing of future experiences. These two functions of memory are often at odds: Remembering specific experiences from the past requires storing idiosyncratic properties that define particular moments in space and time, but by definition such properties will not be shared with similar situations in the future and thus may not be applicable to future situations. We discovered that, when faced with this conflict, the brain prioritizes prediction over encoding. Behavioral tests of recognition and source recall showed that items allowing for prediction of what will appear next based on learned regularities were less likely to be encoded into memory. Brain imaging revealed that the hippocampus was responsible for this interference between statistical learning and episodic memory. The more that the hippocampus predicted the category of an upcoming item, the worse the current item was encoded. This competition may serve an adaptive purpose, focusing encoding on experiences for which we do not yet have a predictive model.

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Statistical prediction of the future impairs episodic encoding of the present

10.1101/851147 ◽

2019 ◽

Cited By ~ 1

Author(s):

Brynn E. Sherman ◽

Nicholas B. Turk-Browne

Keyword(s):

Episodic Memory ◽

Predictive Model ◽

Statistical Learning ◽

Statistical Prediction ◽

Behavioral Tests ◽

The Past ◽

The Future ◽

Episodic Encoding ◽

Past Experiences ◽

The Brain

AbstractMemory is typically thought of as enabling reminiscence about past experiences. However, memory also informs and guides processing of future experiences. These two functions of memory are often at odds: remembering specific experiences from the past requires storing idiosyncratic properties that define particular moments in space and time, but by definition such properties will not be shared with similar situations in the future and thus may not be applicable to future situations. We discovered that, when faced with this conflict, the brain prioritizes prediction over encoding. Behavioral tests of recognition and source recall showed that items allowing for prediction of what will appear next based on learned regularities were less likely to be encoded into memory. Brain imaging revealed that the hippocampus was responsible for this interference between statistical learning and episodic memory. The more that the hippocampus predicted the category of an upcoming item, the worse the current item was encoded. This competition may serve an adaptive purpose, focusing encoding on experiences for which we do not yet have a predictive model.

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Encoding Processes during Retrieval Tasks

Journal of Cognitive Neuroscience ◽

10.1162/08989290151137430 ◽

2001 ◽

Vol 13 (3) ◽

pp. 406-415 ◽

Cited By ~ 124

Author(s):

Randy L. Buckner ◽

Mark E. Wheeler ◽

Margaret A. Sheridan

Keyword(s):

Episodic Memory ◽

Memory Retrieval ◽

Memory Encoding ◽

Imaging Data ◽

Repeated Testing ◽

Retrieval Task ◽

Partial Explanation ◽

New Words ◽

Episodic Encoding ◽

Incidental Encoding

Episodic memory encoding is pervasive across many kinds of task and often arises as a secondary processing effect in tasks that do not require intentional memorization. To illustrate the pervasive nature of information processing that leads to epeisodic encoding, a form of incidental encoding was explored based on the “Testing” phenomenon: The incidental-encoding task was an episodic memory retrieval task. Behavioral data showed that performing a memory retrieval task was as effedctive as intentional instructions at promoting episodic encoding. During fMRI imaging, subjedcts veiewed old and new words adn indicated whether they remembered them. Relevant to encoding, the fate of the new words was examined using a second, surprise test of recognition after the imaging session, fMRI analysis of those new words that were later remembered revealed greater activity in left frontal regions than those that were later forgotten-the same pattern of results as previously observed for traditional incidental and intentional episodic encoding tasks. This finding may offer a partial explanation for why repeated testing improves memory performance. Furthermore, the observation of correlates of episodic memory encoding during retrieval tasks challenges some interpretations that aris from direct comparisons between: encoding tasks and “retrieval tasks” in imaging data. Encoding processes and their neural correlates may arise in many tasks, even those nominally labeled as retrieval tasks by the experimenter.

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