Tracking prototype and exemplar representations in the brain across learning

There is a long-standing debate about whether categories are represented by individual category members (exemplars) or by the central tendency abstracted from individual members (prototypes). Neuroimaging studies have shown neural evidence for either exemplar representations or prototype representations, but not both. Presently, we asked whether it is possible for multiple types of category representations to exist within a single task. We designed a categorization task to promote both exemplar and prototype representations and tracked their formation across learning. We found only prototype correlates during the final test. However, interim tests interspersed throughout learning showed prototype and exemplar representations across distinct brain regions that aligned with previous studies: prototypes in ventromedial prefrontal cortex and anterior hippocampus and exemplars in inferior frontal gyrus and lateral parietal cortex. These findings indicate that, under the right circumstances, individuals may form representations at multiple levels of specificity, potentially facilitating a broad range of future decisions.

Download Full-text

Model-based fMRI reveals co-existing specific and generalized concept representations

10.1101/2020.05.26.117507 ◽

2020 ◽

Author(s):

Caitlin R. Bowman ◽

Takako Iwashita ◽

Dagmar Zeithamova

Keyword(s):

Prefrontal Cortex ◽

Parietal Cortex ◽

Inferior Frontal Gyrus ◽

Ventromedial Prefrontal Cortex ◽

Central Tendency ◽

Single Task ◽

Categorization Task ◽

Multiple Levels ◽

Concept Representations ◽

The Right

AbstractThere has been a long-standing debate about whether categories are represented by individual category members (exemplars) or by the central tendency abstracted from individual members (prototypes). Across neuroimaging studies, there has been neural evidence for either exemplar representations or prototype representations, but not both. In the present study, we asked whether it is possible for individuals to form multiple types of category representations within a single task. We designed a categorization task to promote both exemplar and prototype representations, and we tracked their formation across learning. We found evidence for co-existing prototype and exemplar representations in brain in regions that aligned with previous studies: prototypes in ventromedial prefrontal cortex and anterior hippocampus and exemplars in inferior frontal gyrus and lateral parietal cortex. These findings show that, under the right circumstances, individuals may form representations at multiple levels of specificity, potentially facilitating a broad range of future memory-based decisions.

Download Full-text

Reducing future fears by suppressing the brain mechanisms underlying episodic simulation

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1606604114 ◽

2016 ◽

Vol 113 (52) ◽

pp. E8492-E8501 ◽

Cited By ~ 21

Author(s):

Roland G. Benoit ◽

Daniel J. Davies ◽

Michael C. Anderson

Keyword(s):

Prefrontal Cortex ◽

Dorsolateral Prefrontal Cortex ◽

Ventromedial Prefrontal Cortex ◽

Episodic Simulation ◽

Dorsolateral Prefrontal ◽

Future Events ◽

The Right ◽

Development Of Anxiety ◽

The Brain

Imagining future events conveys adaptive benefits, yet recurrent simulations of feared situations may help to maintain anxiety. In two studies, we tested the hypothesis that people can attenuate future fears by suppressing anticipatory simulations of dreaded events. Participants repeatedly imagined upsetting episodes that they feared might happen to them and suppressed imaginings of other such events. Suppressing imagination engaged the right dorsolateral prefrontal cortex, which modulated activation in the hippocampus and in the ventromedial prefrontal cortex (vmPFC). Consistent with the role of the vmPFC in providing access to details that are typical for an event, stronger inhibition of this region was associated with greater forgetting of such details. Suppression further hindered participants’ ability to later freely envision suppressed episodes. Critically, it also reduced feelings of apprehensiveness about the feared scenario, and individuals who were particularly successful at down-regulating fears were also less trait-anxious. Attenuating apprehensiveness by suppressing simulations of feared events may thus be an effective coping strategy, suggesting that a deficiency in this mechanism could contribute to the development of anxiety.

Download Full-text

Feel between the Lines: Implied Emotion in Sentence Comprehension

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00798 ◽

2015 ◽

Vol 27 (8) ◽

pp. 1528-1541 ◽

Cited By ~ 12

Author(s):

Vicky Tzuyin Lai ◽

Roel M. Willems ◽

Peter Hagoort

Keyword(s):

Prefrontal Cortex ◽

Sentence Comprehension ◽

Inferior Frontal Gyrus ◽

Building Blocks ◽

Brain Regions ◽

Word Retrieval ◽

Negative Sentence ◽

Sentence Meaning ◽

Sentence Level ◽

The Brain

This study investigated the brain regions for the comprehension of implied emotion in sentences. Participants read negative sentences without negative words, for example, “The boy fell asleep and never woke up again,” and their neutral counterparts “The boy stood up and grabbed his bag.” This kind of negative sentence allows us to examine implied emotion derived at the sentence level, without associative emotion coming from word retrieval. We found that implied emotion in sentences, relative to neutral sentences, led to activation in some emotion-related areas, including the medial prefrontal cortex, the amygdala, and the insula, as well as certain language-related areas, including the inferior frontal gyrus, which has been implicated in combinatorial processing. These results suggest that the emotional network involved in implied emotion is intricately related to the network for combinatorial processing in language, supporting the view that sentence meaning is more than simply concatenating the meanings of its lexical building blocks.

Download Full-text

Connections of the Human Orbitofrontal Cortex and Inferior Frontal Gyrus

Cerebral Cortex ◽

10.1093/cercor/bhaa160 ◽

2020 ◽

Vol 30 (11) ◽

pp. 5830-5843 ◽

Cited By ~ 3

Author(s):

Chih-Chin Heather Hsu ◽

Edmund T Rolls ◽

Chu-Chung Huang ◽

Shin Tai Chong ◽

Chun-Yi Zac Lo ◽

...

Keyword(s):

Prefrontal Cortex ◽

Anterior Cingulate Cortex ◽

Orbitofrontal Cortex ◽

Inferior Frontal Gyrus ◽

Cingulate Cortex ◽

Ventromedial Prefrontal Cortex ◽

Anterior Cingulate ◽

Inferior Parietal Cortex ◽

Temporal Pole ◽

The Right

Abstract The direct connections of the orbitofrontal cortex (OFC) were traced with diffusion tractography imaging and statistical analysis in 50 humans, to help understand better its roles in emotion and its disorders. The medial OFC and ventromedial prefrontal cortex have direct connections with the pregenual and subgenual parts of the anterior cingulate cortex; all of which are reward-related areas. The lateral OFC (OFClat) and its closely connected right inferior frontal gyrus (rIFG) have direct connections with the supracallosal anterior cingulate cortex; all of which are punishment or nonreward-related areas. The OFClat and rIFG also have direct connections with the right supramarginal gyrus and inferior parietal cortex, and with some premotor cortical areas, which may provide outputs for the OFClat and rIFG. Another key finding is that the ventromedial prefrontal cortex shares with the medial OFC especially strong outputs to the nucleus accumbens and olfactory tubercle, which comprise the ventral striatum, whereas the other regions have more widespread outputs to the striatum. Direct connections of the OFC and IFG were with especially the temporal pole part of the temporal lobe. The left IFG, which includes Broca’s area, has direct connections with the left angular and supramarginal gyri.

Download Full-text

Decreased effective connection from the parahippocampal gyrus to the prefrontal cortex in Internet gaming disorder: A MVPA and spDCM study

Journal of Behavioral Addictions ◽

10.1556/2006.2020.00012 ◽

2020 ◽

Vol 9 (1) ◽

pp. 105-115 ◽

Cited By ~ 1

Author(s):

Ziliang Wang ◽

Haohao Dong ◽

Xiaoxia Du ◽

Jin-Tao Zhang ◽

Guang-Heng Dong

Keyword(s):

Prefrontal Cortex ◽

Internet Gaming Disorder ◽

Brain Regions ◽

Parahippocampal Gyrus ◽

Series Data ◽

Support Vector ◽

Gaming Disorder ◽

Internet Gaming ◽

The Right ◽

The Brain

Abstract Objectives Understanding the neural mechanisms underlying Internet gaming disorder (IGD) is essential for the condition's diagnosis and treatment. Nevertheless, the pathological mechanisms of IGD remain elusive at present. Hence, we employed multi-voxel pattern analysis (MVPA) and spectral dynamic causal modeling (spDCM) to explore this issue. Methods Resting-state fMRI data were collected from 103 IGD subjects (male = 57) and 99 well-matched recreational game users (RGUs, male = 51). Regional homogeneity was calculated as the feature for MVPA based on the support vector machine (SVM) with leave-one- out cross-validation. Mean time series data extracted from the brain regions in accordance with the MVPA results were used for further spDCM analysis. Results Results display a high accuracy of 82.67% (sensitivity of 83.50% and specificity of 81.82%) in the classification of the two groups. The most discriminative brain regions that contributed to the classification were the bilateral parahippocampal gyrus (PG), right anterior cingulate cortex (ACC), and middle frontal gyrus (MFG). Significant correlations were found between addiction severity (IAT and DSM scores) and the ReHo values of the brain regions that contributed to the classification. Moreover, the results of spDCM showed that compared with RGU, IGD showed decreased effective connectivity from the left PG to the right MFG and from the right PG to the ACC and decreased self-connection in the right PG. Conclusions These results show that the weakening of the PG and its connection with the prefrontal cortex, including the ACC and MFG, may be an underlying mechanism of IGD.

Download Full-text

A Voxel-Based Morphometry Study of the Brain of University Students Majoring in Music and Nonmusic Disciplines

Behavioural Neurology ◽

10.1155/2015/274919 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 7

Author(s):

Kanako Sato ◽

Eiji Kirino ◽

Shoji Tanaka

Keyword(s):

University Students ◽

Developmental Stages ◽

Musical Training ◽

Inferior Frontal Gyrus ◽

Superior Temporal Gyrus ◽

Brain Regions ◽

Voxel Based Morphometry ◽

Middle Occipital Gyrus ◽

The Right ◽

The Brain

The brain changes flexibly due to various experiences during the developmental stages of life. Previous voxel-based morphometry (VBM) studies have shown volumetric differences between musicians and nonmusicians in several brain regions including the superior temporal gyrus, sensorimotor areas, and superior parietal cortex. However, the reported brain regions depend on the study and are not necessarily consistent. By VBM, we investigated the effect of musical training on the brain structure by comparing university students majoring in music with those majoring in nonmusic disciplines. All participants were right-handed healthy Japanese females. We divided the nonmusic students into two groups and therefore examined three groups: music expert (ME), music hobby (MH), and nonmusic (NM) group. VBM showed that the ME group had the largest gray matter volumes in the right inferior frontal gyrus (IFG; BA 44), left middle occipital gyrus (BA 18), and bilateral lingual gyrus. These differences are considered to be caused by neuroplasticity during long and continuous musical training periods because the MH group showed intermediate volumes in these regions.

Download Full-text

Age differences in ventromedial prefrontal cortex functional connectivity during socioemotional content processing

Social Behavior and Personality An International Journal ◽

10.2224/sbp.9380 ◽

2020 ◽

Vol 48 (7) ◽

pp. 1-19

Author(s):

Ryan T. Daley ◽

Holly J. Bowen ◽

Eric C. Fields ◽

Angela Gutchess ◽

Elizabeth A. Kensinger

Keyword(s):

Prefrontal Cortex ◽

Functional Connectivity ◽

Inferior Frontal Gyrus ◽

Age Groups ◽

Emotional Content ◽

Ventromedial Prefrontal Cortex ◽

Anterior Cingulate ◽

Supramarginal Gyrus ◽

Age Related ◽

Content Processing

Self-relevance effects are often confounded by the presence of emotional content, rendering it difficult to determine how brain networks functionally connected to the ventromedial prefrontal cortex (vmPFC) are affected by the independent contributions of self-relevance and emotion. This difficulty is complicated by age-related changes in functional connectivity between the vmPFC and other default mode network regions, and regions typically associated with externally oriented networks. We asked groups of younger and older adults to imagine placing emotional and neutral objects in their home or a stranger's home. An age-invariant vmPFC cluster showed increased activation for self-relevant and emotional content processing. Functional connectivity analyses revealed age × self-relevance interactions in vmPFC connectivity with the anterior cingulate cortex. There were also age × emotion interactions in vmPFC functional connectivity with the anterior insula, orbitofrontal gyrus, inferior frontal gyrus, and supramarginal gyrus. Interactions occurred in regions with the greatest differences between the age groups, as revealed by conjunction analyses. Implications of the findings are discussed.

Download Full-text

The Role of the Right Prefrontal Cortex in Self-evaluation of the Face: A Functional Magnetic Resonance Imaging Study

Journal of Cognitive Neuroscience ◽

10.1162/jocn.2008.20024 ◽

2008 ◽

Vol 20 (2) ◽

pp. 342-355 ◽

Cited By ~ 69

Author(s):

Tomoyo Morita ◽

Shoji Itakura ◽

Daisuke N. Saito ◽

Satoshi Nakashita ◽

Tokiko Harada ◽

...

Keyword(s):

Prefrontal Cortex ◽

Face Recognition ◽

Inferior Frontal Gyrus ◽

Video Recording ◽

Imaging Study ◽

The Self ◽

Anterior Cingulate ◽

Precentral Gyrus ◽

Self Evaluation ◽

The Right

Individuals can experience negative emotions (e.g., embarrassment) accompanying self-evaluation immediately after recognizing their own facial image, especially if it deviates strongly from their mental representation of ideals or standards. The aim of this study was to identify the cortical regions involved in self-recognition and self-evaluation along with self-conscious emotions. To increase the range of emotions accompanying self-evaluation, we used facial feedback images chosen from a video recording, some of which deviated significantly from normal images. In total, 19 participants were asked to rate images of their own face (SELF) and those of others (OTHERS) according to how photogenic they appeared to be. After scanning the images, the participants rated how embarrassed they felt upon viewing each face. As the photogenic scores decreased, the embarrassment ratings dramatically increased for the participant's own face compared with those of others. The SELF versus OTHERS contrast significantly increased the activation of the right prefrontal cortex, bilateral insular cortex, anterior cingulate cortex, and bilateral occipital cortex. Within the right prefrontal cortex, activity in the right precentral gyrus reflected the trait of awareness of observable aspects of the self; this provided strong evidence that the right precentral gyrus is specifically involved in self-face recognition. By contrast, activity in the anterior region, which is located in the right middle inferior frontal gyrus, was modulated by the extent of embarrassment. This finding suggests that the right middle inferior frontal gyrus is engaged in self-evaluation preceded by self-face recognition based on the relevance to a standard self.

Download Full-text

The Cortical Organization of Writing Sequence: Evidence From Observing Chinese Characters in Motion

10.21203/rs.3.rs-285417/v1 ◽

2021 ◽

Author(s):

Zhaoqi Zhang ◽

Qiming Yuan ◽

Zeping Liu ◽

Man Zhang ◽

Junjie Wu ◽

...

Keyword(s):

Structural Equation ◽

Chinese Character ◽

Inferior Frontal Gyrus ◽

Hierarchical Control ◽

Brain Regions ◽

Brain Network ◽

Equation Model ◽

Chinese Characters ◽

General Motor ◽

The Right

Abstract Writing sequences play an important role in handwriting of Chinese characters. However, little is known regarding the integral brain patterns and network mechanisms of processing Chinese character writing sequences. The present study decoded brain patterns during observing Chinese characters in motion by using multi-voxel pattern analysis (MVPA), meta-analytic decoding analysis, and extended unified structural equation model (euSEM). We found that perception of Chinese character writing sequence recruited brain regions not only for general motor schema processing, i.e., the right inferior frontal gyrus, shifting and inhibition functions, i.e., the right postcentral gyrus and bilateral pre-SMA/dACC, but also for sensorimotor functions specific for writing sequences. More importantly, these brain regions formed a cooperatively top-down brain network where information was transmitted from brain regions for general motor schema processing to those specific for writing sequences. These findings not only shed light on the neural mechanisms of Chinese character writing sequences, but also extend the hierarchical control model on motor schema processing.

Download Full-text

Subjective value and decision entropy are jointly encoded by aligned gradients across the human brain

10.1101/2020.02.18.954362 ◽

2020 ◽

Author(s):

Sebastian Bobadilla-Suarez ◽

Olivia Guest ◽

Bradley C. Love

Keyword(s):

Prefrontal Cortex ◽

Human Brain ◽

Ventromedial Prefrontal Cortex ◽

Neural Representation ◽

Retrospective Evaluation ◽

Systematic Fashion ◽

Subjective Value ◽

Fmri Analysis ◽

The Relationship ◽

The Brain

AbstractRecent work has considered the relationship between value and confidence in both behavior and neural representation. Here we evaluated whether the brain organizes value and confidence signals in a systematic fashion that reflects the overall desirability of options. If so, regions that respond to either increases or decreases in both value and confidence should be widespread. We strongly confirmed these predictions through a model-based fMRI analysis of a mixed gambles task that assessed subjective value (SV) and inverse decision entropy (iDE), which is related to confidence. Purported value areas more strongly signalled iDE than SV, underscoring how intertwined value and confidence are. A gradient tied to the desirability of actions transitioned from positive SV and iDE in ventromedial prefrontal cortex to negative SV and iDE in dorsal medial prefrontal cortex. This alignment of SV and iDE signals could support retrospective evaluation to guide learning and subsequent decisions.

Download Full-text