Choice-dependent cross-modal interaction in the medial prefrontal cortex of rats

AbstractCross-modal interaction (CMI) could significantly influence the perceptional or decision-making process in many circumstances. However, it remains poorly understood what integrative strategies are employed by the brain to deal with different task contexts. To explore it, we examined neural activities of the medial prefrontal cortex (mPFC) of rats performing cue-guided two-alternative forced-choice tasks. In a task requiring rats to discriminate stimuli based on auditory cue, the simultaneous presentation of an uninformative visual cue substantially strengthened mPFC neurons' capability of auditory discrimination mainly through enhancing the response to the preferred cue. Doing this also increased the number of neurons revealing a cue preference. If the task was changed slightly and a visual cue, like the auditory, denoted a specific behavioral direction, mPFC neurons frequently showed a different CMI pattern with an effect of cross-modal enhancement best evoked in information-congruent multisensory trials. In a choice free task, however, the majority of neurons failed to show a cross-modal enhancement effect and cue preference. These results indicate that CMI at the neuronal level is context-dependent in a way that differs from what has been shown in previous studies.

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Context-dependent cross-modal interaction in the medial prefrontal cortex of rats

10.21203/rs.3.rs-72344/v1 ◽

2020 ◽

Author(s):

Mengyao Zheng ◽

Jinghong Xu ◽

Les Keniston ◽

Jing Wu ◽

Song Chang ◽

...

Keyword(s):

Prefrontal Cortex ◽

Medial Prefrontal Cortex ◽

Simultaneous Presentation ◽

Enhancement Effect ◽

Modal Interaction ◽

Visual Cue ◽

Neural Activities ◽

Context Dependent ◽

Forced Choice Tasks ◽

Choice Tasks

Abstract Cross-modal interaction (CMI) could significantly influence the perceptional or decision-making process in many circumstances. However, it remains poorly understood what integrative strategies are employed by the brain to deal with different task contexts. To explore it, we examined neural activities of the medial prefrontal cortex (mPFC) of rats performing cue-guided two-alternative forced-choice tasks. In a task requiring rats to discriminate stimuli based on auditory cue, the simultaneous presentation of an uninformative visual cue substantially strengthened mPFC neurons' capability of auditory discrimination mainly through enhancing the response to the preferred cue. Doing this also increased the number of neurons revealing a cue preference. If the task was changed slightly and a visual cue, like the auditory, denoted a specific behavioral direction, mPFC neurons frequently showed a different CMI pattern with an effect of cross-modal enhancement best evoked in information-congruent multisensory trials. In a choice free task, however, the majority of neurons failed to show a cross-modal enhancement effect and cue preference. These results indicate that CMI at the neuronal level is context-dependent in a way that differs from what has been shown in previous studies.

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Laser technique for anatomical-functional study of the medial prefrontal cortex of the brain

10.1117/12.347469 ◽

1999 ◽

Author(s):

Laura Sanchez-Huerta ◽

Adan Hernandez ◽

Griselda Ayala ◽

Javier Marroquin ◽

Adriana B. Silva ◽

...

Keyword(s):

Prefrontal Cortex ◽

Medial Prefrontal Cortex ◽

Functional Study ◽

Laser Technique ◽

The Brain

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A detection theoretic explanation of blindsight suggests a link between conscious perception and metacognition

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2011.0380 ◽

2012 ◽

Vol 367 (1594) ◽

pp. 1401-1411 ◽

Cited By ~ 42

Author(s):

Yoshiaki Ko ◽

Hakwan Lau

Keyword(s):

Prefrontal Cortex ◽

Signal Detection Theory ◽

Computational Simulation ◽

Forced Choice ◽

Simulation Data ◽

Visual Tasks ◽

Trial Basis ◽

Forced Choice Tasks ◽

Choice Tasks ◽

Confidence Ratings

Blindsight refers to the rare ability of V1-damaged patients to perform visual tasks such as forced-choice discrimination, even though these patients claim not to consciously see the relevant stimuli. This striking phenomenon can be described in the formal terms of signal detection theory. (i) Blindsight patients use an unusually conservative criterion to detect targets. (ii) In discrimination tasks, their confidence ratings are low and (iii) such confidence ratings poorly predict task accuracy on a trial-by-trial basis. (iv) Their detection capacity ( d ′) is lower than expected based on their performance in forced-choice tasks. We propose a unifying explanation that accounts for these features: that blindsight is due to a failure to represent and update the statistical information regarding the internal visual neural response, i.e. a failure in metacognition. We provide computational simulation data to demonstrate that this model can qualitatively account for the detection theoretic features of blindsight. Because such metacognitive mechanisms are likely to depend on the prefrontal cortex, this suggests that although blindsight is typically due to damage to the primary visual cortex, distal influence to the prefrontal cortex by such damage may be critical. Recent brain imaging evidence supports this view.

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Integrating memories: Congruency and reactivation aid memory integration through reinstatement of prior knowledge

10.1101/716076 ◽

2019 ◽

Author(s):

Marlieke T.R. van Kesteren ◽

Paul Rignanese ◽

Pierre G. Gianferrara ◽

Lydia Krabbendam ◽

Martijn Meeter

Keyword(s):

Prefrontal Cortex ◽

Prior Knowledge ◽

Medial Prefrontal Cortex ◽

Medial Temporal Lobe ◽

Knowledge Building ◽

Activity Patterns ◽

Brain Regions ◽

Memory Integration ◽

The Brain ◽

Parahippocampal Place Area

AbstractBuilding consistent knowledge schemas that organize information and guide future learning is of great importance in everyday life. Such knowledge building is suggested to occur through reinstatement of prior knowledge during new learning in stimulus-specific brain regions. This process is proposed to yield integration of new with old memories, supported by the medial prefrontal cortex (mPFC) and medial temporal lobe (MTL). Possibly as a consequence, congruency of new information with prior knowledge is known to enhance subsequent memory. Yet, it is unknown how reactivation and congruency interact to optimize memory integration processes that lead to knowledge schemas. To investigate this question, we here used an adapted AB-AC inference paradigm in combination with functional Magnetic Resonance Imaging (fMRI). Participants first studied an AB-association followed by an AC-association, so B (a scene) and C (an object) were indirectly linked through their common association with A (an unknown pseudoword). BC-associations were either congruent or incongruent with prior knowledge (e.g. a bathduck or a hammer in a bathroom), and participants were asked to report subjective reactivation strength for B while learning AC. Behaviorally, both the congruency and reactivation measures enhanced memory integration. In the brain, these behavioral effects related to univariate and multivariate parametric effects of congruency and reactivation on activity patterns in the MTL, mPFC, and Parahippocampal Place Area (PPA). Moreover, mPFC exhibited larger connectivity with the PPA for more congruent associations. These outcomes provide insights into the neural mechanisms underlying memory integration enhancement, which can be important for educational learning.Significance statementHow does our brain build knowledge through integrating information that is learned at different periods in time? This question is important in everyday learning situations such as educational settings. Using an inference paradigm, we here set out to investigate how congruency with, and active reactivation of previously learned information affects memory integration processes in the brain. Both these factors were found to relate to activity in memory-related regions such as the medial prefrontal cortex (mPFC) and the hippocampus. Moreover, activity in the parahippocampal place area (PPA), assumed to reflect reinstatement of the previously learned associate, was found to predict subjective reactivation strength. These results show how we can moderate memory integration processes to enhance subsequent knowledge building.

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Schema support for forming inferences in the human brain

10.1101/2021.11.15.466820 ◽

2021 ◽

Author(s):

John Philippe Paulus ◽

Carlo Vignali ◽

Marc N Coutanche

Keyword(s):

Prefrontal Cortex ◽

Human Brain ◽

Medial Prefrontal Cortex ◽

Neural Representations ◽

Memory Integration ◽

New Information ◽

Neural Integration ◽

Two Factors ◽

Memory Schema ◽

The Brain

Associative inference, the process of drawing novel links between existing knowledge to rapidly integrate associated information, is supported by the hippocampus and neocortex. Within the neocortex, the medial prefrontal cortex (mPFC) has been implicated in the rapid cortical learning of new information that is congruent with an existing framework of knowledge, or schema. How the brain integrates associations to form inferences, specifically how inferences are represented, is not well understood. In this study, we investigate how the brain uses schemas to facilitate memory integration in an associative inference paradigm (A-B-C-D). We conducted two event-related fMRI experiments in which participants retrieved previously learned direct (AB, BC, CD) and inferred (AC, AD) associations between word pairs for items that are schema congruent or incongruent. Additionally, we investigated how two factors known to affect memory, a delay with sleep, and reward, modulate the neural integration of associations within, and between, schema. Schema congruency was found to benefit the integration of associates, but only when retrieval immediately follows learning. RSA revealed that neural patterns of inferred pairs (AC) in the PHc, mPFC, and posHPC were more similar to their constituents (AB and BC) when the items were schema congruent, suggesting that schema facilitates the assimilation of paired items into a single inferred unit containing all associated elements. Furthermore, a delay with sleep, but not reward, impacted the assimilation of inferred pairs. Our findings reveal that the neural representations of overlapping associations are integrated into novel representations through the support of memory schema.

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Proteomic Profiling of Astrocytic O-GlcNAc Transferase-Related Proteins in the Medial Prefrontal Cortex

Frontiers in Molecular Neuroscience ◽

10.3389/fnmol.2021.729975 ◽

2021 ◽

Vol 14 ◽

Author(s):

Jun Fan ◽

Qiu-Ling Zhong ◽

Ran Mo ◽

Cheng-Lin Lu ◽

Jing Ren ◽

...

Keyword(s):

Prefrontal Cortex ◽

Medial Prefrontal Cortex ◽

Transferase Activity ◽

Proteomic Profiling ◽

Major Energy Source ◽

Altered Proteins ◽

Glcnac Transferase ◽

Related Proteins ◽

The Brain

The medial prefrontal cortex (mPFC), a key part of the brain networks that are closely related to the regulation of behavior, acts as a key regulator in emotion, social cognition, and decision making. Astrocytes are the majority cell type of glial cells, which play a significant role in a number of processes and establish a suitable environment for the functioning of neurons, including the brain energy metabolism. Astrocyte’s dysfunction in the mPFC has been implicated in various neuropsychiatric disorders. Glucose is a major energy source in the brain. In glucose metabolism, part of glucose is used to convert UDP-GlcNAc as a donor molecule for O-GlcNAcylation, which is controlled by a group of enzymes, O-GlcNAc transferase enzyme (OGT), and O-GlcNAcase (OGA). However, the role of O-GlcNAcylation in astrocytes is almost completely unknown. Our research showed that astrocytic OGT could influence the expression of proteins in the mPFC. Most of these altered proteins participate in metabolic processes, transferase activity, and biosynthetic processes. GFAP, an astrocyte maker, was increased after OGT deletion. These results provide a framework for further study on the role of astrocytic OGT/O-GlcNAcylation in the mPFC.

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