scholarly journals Representational organization of novel task sets during proactive encoding

2019 ◽  
Author(s):  
Ana F. Palenciano ◽  
Carlos González-García ◽  
Juan E. Arco ◽  
Luiz Pessoa ◽  
María Ruz
Keyword(s):  
Prefrontal Cortex ◽  
Neural Coding ◽  
Brain Regions ◽  
Stimulus Category ◽  
General Effect ◽  
Lateral Prefrontal Cortex ◽  
Representational Space ◽  
Task Encoding ◽  
Brain Data ◽  
The Brain

AbstractRecent multivariate analyses of brain data have boosted our understanding of the organizational principles that shape neural coding. However, most of this progress has focused on perceptual visual regions (Connolly et al., 2012), whereas far less is known about the organization of more abstract, action-oriented representations. In this study, we focused on humans’ remarkable ability to turn novel instructions into actions. While previous research shows that instruction encoding is tightly linked to proactive activations in fronto-parietal brain regions, little is known about the structure that orchestrates such anticipatory representation. We collected fMRI data while participants (both males and females) followed novel complex verbal rules that varied across control-related variables (integrating within/across stimuli dimensions, response complexity, target category) and reward expectations. Using Representational Similarity Analysis (Kriegeskorte et al., 2008) we explored where in the brain these variables explained the organization of novel task encoding, and whether motivation modulated these representational spaces. Instruction representations in the lateral prefrontal cortex were structured by the three control-related variables, while intraparietal sulcus encoded response complexity and the fusiform gyrus and precuneus organized its activity according to the relevant stimulus category. Reward exerted a general effect, increasing the representational similarity among different instructions, which was robustly correlated with behavioral improvements. Overall, our results highlight the flexibility of proactive task encoding, governed by distinct representational organizations in specific brain regions. They also stress the variability of motivation-control interactions, which appear to be highly dependent on task attributes such as complexity or novelty.Significance StatementIn comparison with other primates, humans display a remarkable success in novel task contexts thanks to our ability to transform instructions into effective actions. This skill is associated with proactive task-set reconfigurations in fronto-parietal cortices. It remains yet unknown, however, how the brain encodes in anticipation the flexible, rich repertoire of novel tasks that we can achieve. Here we explored cognitive control and motivation-related variables that might orchestrate the representational space for novel instructions. Our results showed that different dimensions become relevant for task prospective encoding depending on the brain region, and that the lateral prefrontal cortex simultaneously organized task representations following different control-related variables. Motivation exerted a general modulation upon this process, diminishing rather than increasing distances among instruction representations.

scholarly journals Convergence of heteromodal lexical retrieval in the lateral prefrontal cortex

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alexander A. Aabedi ◽  
Sofia Kakaizada ◽  
Jacob S. Young ◽  
Jasleen Kaur ◽  
Olivia Wiese ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Picture Naming ◽  
Cognitive Rehabilitation ◽  
Tumor Model ◽  
Brain Regions ◽  
Support Vector ◽  
Lexical Retrieval ◽  
Lateral Prefrontal Cortex ◽  
Lesion Symptom Mapping ◽  
Single Construct

AbstractLexical retrieval requires selecting and retrieving the most appropriate word from the lexicon to express a desired concept. Few studies have probed lexical retrieval with tasks other than picture naming, and when non-picture naming lexical retrieval tasks have been applied, both convergent and divergent results emerged. The presence of a single construct for auditory and visual processes of lexical retrieval would influence cognitive rehabilitation strategies for patients with aphasia. In this study, we perform support vector regression lesion-symptom mapping using a brain tumor model to test the hypothesis that brain regions specifically involved in lexical retrieval from visual and auditory stimuli represent overlapping neural systems. We find that principal components analysis of language tasks revealed multicollinearity between picture naming, auditory naming, and a validated measure of word finding, implying the existence of redundant cognitive constructs. Nonparametric, multivariate lesion-symptom mapping across participants was used to model accuracies on each of the four language tasks. Lesions within overlapping clusters of 8,333 voxels and 21,512 voxels in the left lateral prefrontal cortex (PFC) were predictive of impaired picture naming and auditory naming, respectively. These data indicate a convergence of heteromodal lexical retrieval within the PFC.

scholarly journals The Effects of Tryptamine Psychedelics in the Brain: A meta-Analysis of Functional and Review of Molecular Imaging Studies

2021 ◽  
Vol 12 ◽  
Author(s):  
João Castelhano ◽  
Gisela Lima ◽  
Marta Teixeira ◽  
Carla Soares ◽  
Marta Pais ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Theory Of Mind ◽  
Molecular Mimicry ◽  
Meta Analysis ◽  
Temporal Cortex ◽  
Brain Regions ◽  
Imaging Studies ◽  
Activation Patterns ◽  
Therapeutic Benefits ◽  
The Brain

There is an increasing interest in the neural effects of psychoactive drugs, in particular tryptamine psychedelics, which has been incremented by the proposal that they have potential therapeutic benefits, based on their molecular mimicry of serotonin. It is widely believed that they act mainly through 5HT2A receptors but their effects on neural activation of distinct brain systems are not fully understood. We performed a quantitative meta-analysis of brain imaging studies to investigate the effects of substances within this class (e.g., LSD, Psilocybin, DMT, Ayahuasca) in the brain from a molecular and functional point of view. We investigated the question whether the changes in activation patterns and connectivity map into regions with larger 5HT1A/5HT2A receptor binding, as expected from indolaemine hallucinogens (in spite of the often reported emphasis only on 5HT2AR). We did indeed find that regions with changed connectivity and/or activation patterns match regions with high density of 5HT2A receptors, namely visual BA19, visual fusiform regions in BA37, dorsal anterior and posterior cingulate cortex, medial prefrontal cortex, and regions involved in theory of mind such as the surpramarginal gyrus, and temporal cortex (rich in 5HT1A receptors). However, we also found relevant patterns in other brain regions such as dorsolateral prefrontal cortex. Moreover, many of the above-mentioned regions also have a significant density of both 5HT1A/5HT2A receptors, and available PET studies on the effects of psychedelics on receptor occupancy are still quite scarce, precluding a metanalytic approach. Finally, we found a robust neuromodulatory effect in the right amygdala. In sum, the available evidence points towards strong neuromodulatory effects of tryptamine psychedelics in key brain regions involved in mental imagery, theory of mind and affective regulation, pointing to potential therapeutic applications of this class of substances.

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

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.

scholarly journals Concept generation techniques change patterns of brain activation during engineering design

2020 ◽  
Vol 6 ◽  
Author(s):  
Tripp Shealy ◽  
John Gero ◽  
Mo Hu ◽  
Julie Milovanovic
Keyword(s):  
Prefrontal Cortex ◽  
Morphological Analysis ◽  
Engineering Students ◽  
Near Infrared ◽  
Brain Activation ◽  
Brain Regions ◽  
Concept Generation ◽  
Functional Near Infrared Spectroscopy ◽  
Cognitive Activation ◽  
The Brain

Abstract This paper presents the results of studying the brain activations of 30 engineering students when using three different design concept generation techniques: brainstorming, morphological analysis, and TRIZ. Changes in students’ brain activation in the prefrontal cortex were measured using functional near-infrared spectroscopy. The results are based on the area under the curve analysis of oxygenated hemodynamic response as well as an assessment of functional connectivity using Pearson’s correlation to compare students’ cognitive brain activations using these three different ideation techniques. The results indicate that brainstorming and morphological analysis demand more cognitive activation across the prefrontal cortex (PFC) compared to TRIZ. The highest cognitive activation when brainstorming and using morphological analysis is in the right dorsolateral PFC (DLPFC) and ventrolateral PFC. These regions are associated with divergent thinking and ill-defined problem-solving. TRIZ produces more cognitive activation in the left DLPFC. This region is associated with convergent thinking and making judgments. Morphological analysis and TRIZ also enable greater coordination (i.e., synchronized activation) between brain regions. These findings offer new evidence that structured techniques like TRIZ reduce cognitive activation, change patterns of activation and increase coordination between regions in the brain.

The Neuroscience of Learning Agility

2021 ◽  
pp. 118-142
Author(s):  
Kim E. Ruyle
Keyword(s):  
Emotional Intelligence ◽  
Prefrontal Cortex ◽  
Executive Function ◽  
Limbic System ◽  
Brain Regions ◽  
Learning Agility ◽  
Attention Networks ◽  
The Relationship ◽  
The Brain

“The Neuroscience of Learning Agility” explores the relationship between neurobiology and learning agility. It provides an overview of the organization of the brain, focusing on the roles of the limbic system and the prefrontal cortex and how these particular brain regions relate to personality, executive function, and the metacompetencies of emotional intelligence and learning agility. The neuroscience of learning is discussed, including the brain’s attention networks, neuroplasticity, and biological underpinnings of memory. An argument is posited that the brain’s perceptions of threats directly impacts one’s personality and, by extension, influences one’s level of learning agility. The chapter concludes by providing neuroscience-based suggestions for developing learning agility.

scholarly journals Fluoxetine increases brain MeCP2 immuno-positive cells in a female Mecp2 heterozygous mouse model of Rett syndrome through endogenous serotonin

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Claudia Villani ◽  
Mirjana Carli ◽  
Anna Maria Castaldo ◽  
Giuseppina Sacchetti ◽  
Roberto William Invernizzi
Keyword(s):  
Prefrontal Cortex ◽  
Rett Syndrome ◽  
Motor Coordination ◽  
Antidepressant Drug ◽  
Brain Regions ◽  
Loss Of Function ◽  
Heterozygous Mouse ◽  
Skill Deficit ◽  
Second Year ◽  
The Brain

AbstractMotor skill deficit is a common and invalidating symptom of Rett syndrome (RTT), a rare disease almost exclusively affecting girls during the first/second year of life. Loss-of-function mutations of the methyl-CpG-binding protein2 (MECP2; Mecp2 in rodents) gene is the cause in most patients. We recently found that fluoxetine, a selective serotonin (5-HT) reuptake inhibitor and antidepressant drug, fully rescued motor coordination deficits in Mecp2 heterozygous (Mecp2 HET) mice acting through brain 5-HT. Here, we asked whether fluoxetine could increase MeCP2 expression in the brain of Mecp2 HET mice, under the same schedule of treatment improving motor coordination. Fluoxetine increased the number of MeCP2 immuno-positive (MeCP2+) cells in the prefrontal cortex, M1 and M2 motor cortices, and in dorsal, ventral and lateral striatum. Fluoxetine had no effect in the CA3 region of the hippocampus or in any of the brain regions of WT mice. Inhibition of 5-HT synthesis abolished the fluoxetine-induced rise of MeCP2+ cells. These findings suggest that boosting 5-HT transmission is sufficient to enhance the expression of MeCP2 in several brain regions of Mecp2 HET mice. Fluoxetine-induced rise of MeCP2 could potentially rescue motor coordination and other deficits of RTT.

scholarly journals Linking Models with Brain Measures

2020 ◽  
Author(s):  
Bradley C. Love
Keyword(s):  
Information Flow ◽  
Cognitive Processes ◽  
Brain Activity ◽  
Cognitive Model ◽  
Brain Regions ◽  
Learning Models ◽  
Model Based ◽  
Theoretical Significance ◽  
Brain Data ◽  
The Brain

Linking models and brain measures offers a number of advantages over standard analyses. Models that have been evaluated on previous datasets can provide theoretical constraints and assist in integrating findings across studies. Model-based analyses can be more sensitive and allow for evaluation of hypotheses that would not otherwise be addressable. For example, a cognitive model that is informed from several behavioural studies could be used to examine how multiple cognitive processes unfold across time in the brain. Models can be linked to brain measures in a number of ways. The information flow and constraints can be from model to brain, brain to model, or reciprocal. Likewise, the linkage from model and brain can be univariate or multivariate, as in studies that relate patterns of brain activity with model states. Models have multiple aspects that can be related to different facets of brain activity. This is well illustrated by deep learning models that have multiple layers or representations that can be aligned with different brain regions. Model-based approaches offer a lens on brain data that is complementary to popular multivariate decoding and representational similarity analysis approaches. Indeed, these approaches can realise greater theoretical significance when situated within a model-based approach.

scholarly journals Convergence of Heteromodal Lexical Retrieval in the Lateral Prefrontal Cortex

2020 ◽  
Author(s):  
Alexander Aabedi ◽  
Sofia Kakaizada ◽  
Jacob Young ◽  
Jasleen Kaur ◽  
Olivia Wiese ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Picture Naming ◽  
Cognitive Rehabilitation ◽  
Tumor Model ◽  
Brain Regions ◽  
Support Vector ◽  
Lexical Retrieval ◽  
Lateral Prefrontal Cortex ◽  
Lesion Symptom Mapping ◽  
Single Construct

Abstract Lexical retrieval requires selecting and retrieving the most appropriate word from the lexicon to express a desired concept. Few studies have probed lexical retrieval with tasks other than picture naming, and when non-picture naming lexical retrieval tasks have been applied, both convergent and divergent results emerged. The presence of a single construct for auditory and visual processes of lexical retrieval would influence cognitive rehabilitation strategies for patients with aphasia. In this study, we perform support vector regression lesion-symptom mapping using a brain tumor model to test the hypothesis that brain regions specifically involved in lexical retrieval from visual and auditory stimuli represent overlapping neural systems. We find that principal components analysis of language tasks revealed multicollinearity between picture naming, auditory naming, and a validated measure of word finding, implying the existence of redundant cognitive constructs. Nonparametric, multivariate lesion-symptom mapping across participants was used to model accuracies on each of the four language tasks. Lesions within overlapping clusters of 8,333 voxels and 21,512 voxels in the left lateral prefrontal cortex (PFC) were predictive of impaired picture naming and auditory naming, respectively. These data indicate a convergence of heteromodal lexical retrieval within the PFC.

scholarly journals Tracking prototype and exemplar representations in the brain across learning

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Caitlin R Bowman ◽  
Takako Iwashita ◽  
Dagmar Zeithamova
Keyword(s):  
Prefrontal Cortex ◽  
Inferior Frontal Gyrus ◽  
Brain Regions ◽  
Ventromedial Prefrontal Cortex ◽  
Central Tendency ◽  
Final Test ◽  
Single Task ◽  
Multiple Levels ◽  
The Right ◽  
The Brain

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.

Economic Decision Making, Emotion, and Prefrontal Cortex

2016 ◽  
pp. 122-131 ◽  
Author(s):  
Salim Lahmiri
Keyword(s):  
Decision Making ◽  
Prefrontal Cortex ◽  
Brain Regions ◽  
Economic Decision ◽  
Financial Decision Making ◽  
Economic Decision Making ◽  
Formal Framework ◽  
Financial Decision ◽  
The Relationship ◽  
The Brain

How diverse regions of the brain are coordinated to produce objective-directed decision is the essence of neuroeconomics. Indeed, the latter is a formal framework to describe the involvement of numerous brain regions including frontal, cingulate, parietal cortex, and striatum in economic and financial decision-making process. The purpose of this chapter is to explain the relationship between economic decision making and emotion on one hand, and the relationship between economic decision making and prefrontal cortex on the other hand.

Sign in / Sign up

Export Citation Format

Share Document