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- Bramao, Ines, et al.
(författare)
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Encoding contexts are incidentally reinstated during competitive retrieval and track the temporal dynamics of memory interference
- 2022
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Ingår i: Cerebral Cortex. - : Oxford University Press (OUP). - 1460-2199 .- 1047-3211. ; 32:22, s. 5020-5035
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Tidskriftsartikel (refereegranskat)abstract
- The ability to remember an episode from our past is often hindered by competition from similar events. For example, if we want to remember the article a colleague recommended during the last lab-meeting, we may need to resolve interference from other article recommendations from the same colleague. This study investigates if the contextual features specifying the encoding episodes are incidentally reinstated during competitive memory retrieval. Competition between memories was created through the AB/AC interference paradigm. Individual word-pairs were presented embedded in a slowly drifting real-word like context. Multivariate pattern analysis (MVPA) of high temporal-resolution electroencephalographic (EEG) data was used to investigate context reactivation during memory retrieval. Behaviorally, we observed proactive (but not retroactive) interference; that is, performance for AC competitive retrieval was worse compared to a control DE non-competitive retrieval, whereas AB retrieval did not suffer from competition. Neurally, proactive interference was accompanied by an early reinstatement of the competitor context and interference resolution was associated with the ensuing reinstatement of the target context. Together, these findings provide novel evidence showing that the encoding contexts of competing discrete events are incidentally reinstated during competitive retrieval and that such reinstatement tracks retrieval competition and subsequent interference resolution.
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| 2. |
- Bramao, Ines, et al.
(författare)
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Neural pattern classification reveals the temporal dynamics of competitive memory retrieval
- 2019
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Konferensbidrag (refereegranskat)abstract
- Resolution of interference between competing memories is often critical for remembering. This study employed multivariate pattern analysis (MVPA) of electroencephalographic (EEG) data to investigate the temporal dynamics of retrieval competition and competition resolution. Competition between memories was created through the AB/AC interference paradigm. Memory retrieval of competitive AB and AC cue-associate word pairs was compared with non-competitive DE word pairs. Behavioural results showed worse memory performance for AC compared with DE word pairs, but comparable performance for AB and DE word pairs, revealing proactive without retroactive interference. Critically, the AB, AC and DE word pairs were encoded embedded in a movie with a distinct theme (first-person perspective of underwater, forest, and city environments). We trained classifiers to discriminate patterns of brain activity associated with the movies at encoding. The classifiers were later applied during memory retrieval to track memory reactivation. In an early cue time window, where only the word cue was presented (i.e. A or D), we observed classification performance for non-competitive retrieval, revealing target reactivation, but no classification for competitive retrieval, presumably due to the simultaneous reactivation of target and competitor memories. In a following probe time window, when participants were given a first-letter probe to retrieve the target word (i.e. B/C/E), we observed classification performance ~700 ms after probe onset for the competitive retrieval, revealing the time course of competition resolution. Importantly, classification accuracy in this late time window co-varied with memory performance, that is, with the resolution of proactive interference. This study offers novel insights into the time course of memory competition and competition resolution.
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| 3. |
- Jiang, Jiefeng, et al.
(författare)
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Temporal Dynamics of Memory-guided Cognitive Control and Generalization of Control via Overlapping Associative Memories
- 2020
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Ingår i: The Journal of Neuroscience : the official journal of the Society for Neuroscience. - 1529-2401. ; 40:11, s. 2343-2356
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Tidskriftsartikel (refereegranskat)abstract
- Goal-directed behavior can benefit from proactive adjustments of cognitive control that occur in anticipation of forthcoming cognitive control demands (CCD). Predictions of forthcoming CCD are thought to depend on learning and memory in two ways: First, through direct experience, associative encoding may link previously experienced CCD to its triggering item, such that subsequent encounters with the item serve to cue retrieval of (i.e., predict) the associated CCD. Second, in the absence of direct experience, pattern completion and mnemonic integration mechanisms may allow CCD to be generalized from its associated item to other items related in memory. While extant behavioral evidence documents both types of CCD prediction, the neurocognitive mechanisms giving rise to these predictions remain largely unexplored. Here, we tested two hypotheses: (1) memory-guided predictions about CCD precede control adjustments due to the actual CCD required to perform, and (2) generalization of CCD can be accomplished through integration mechanisms that link partially overlapping CCD—item and item—item associations in memory. Supporting these hypotheses, the temporal dynamics of theta and alpha power in human electroencephalography data (n=43, 26 females) revealed that an associative CCD effect emerges earlier than interaction effects involving actual CCD. Furthermore, generalization of CCD from one item (X) to another item (Y) was predicted by a decrease in alpha power following the presentation of the X—Y pair. These findings advance understanding of the mechanisms underlying memory-guided adjustments of cognitive control.
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