scholarly journals Perceptual and Semantic Components of Memory for Objects and Faces: A PET Study

2001 ◽  
Vol 13 (4) ◽  
pp. 430-443 ◽  
Author(s):  
Jon S. Simons ◽  
Kim S. Graham ◽  
Adrian M. Owen ◽  
Karalyn Patterson ◽  
John R. Hodges
Keyword(s):  
Recognition Memory ◽  
Right Hemisphere ◽  
Temporal Cortex ◽  
Neural Substrates ◽  
Neural Correlates ◽  
Semantic Knowledge ◽  
Inferior Temporal Cortex ◽  
Within Subjects ◽  
Blood Flow Increase ◽  
The Right

Previous studies have suggested differences in the neural substrates of recognition memory when the contributions of perceptual and semantic information are manipulated. In a within-subjects design PET study, we investigated the neural correlates of the following factors: material type (objects or faces), semantic knowledge (familiar or unfamiliar items), and perceptual similarity at study and test (identical or different pictures). There was consistent material-specific lateralization in frontal and temporal lobe regions when the retrieval of different types of nonverbal stimuli was compared, with objects activating bilateral areas and faces preferentially activating the right hemisphere. Retrieval of memories for nameable, familiar items was associated with increased activation in the left ventrolateral prefrontal cortex, while memory for unfamiliar items involved occipital regions. Recognition memory for different pictures of the same item at study and test produced blood flow increase in left inferior temporal cortex. These results have implications for our understanding of the neural correlates of perceptual and semantic contributions to recognition memory.

A Functional Neuroimaging Description of Two Deep Dyslexic Patients

1998 ◽  
Vol 10 (3) ◽  
pp. 303-315 ◽  
Author(s):  
C. J. Price ◽  
D. Howard ◽  
K. Patterson ◽  
E. A. Warburton ◽  
K. J. Friston ◽  
...  
Keyword(s):  
Left Hemisphere ◽  
Word Processing ◽  
Right Hemisphere ◽  
Temporal Cortex ◽  
Inferior Temporal Cortex ◽  
Broca's Area ◽  
Enhanced Activity ◽  
Left Posterior ◽  
Deep Dyslexia ◽  
The Right

Deep dyslexia is a striking reading disorder that results from left-hemisphere brain damage and is characterized by semantic errors in reading single words aloud (e.g., reading spirit as whisky). Two types of explanation for this syndrome have been advanced. One is that deep dyslexia results from a residual left-hemisphere reading system that has lost the ability to pronounce a printed word without reference to meaning. The second is that deep dyslexia reflects right-hemisphere word processing. Although previous attempts to adjudicate between these hypotheses have been inconclusive, the controversy can now be addressed by mapping functional anatomy. In this study, we demonstrate that reading by two deep dyslexic patients (CJ and JG) involves normal or enhanced activity in spared left-hemisphere regions associated with naming (Broca's area and the left posterior inferior temporal cortex) and with the meanings of words (the left posterior temporo-parietal cortex and the left anterior temporal cortex). In the right-hemisphere homologues of these regions, there was inconsistent activation within the normal group and between the deep dyslexic patients. One (CJ) showed enhanced activity (relative to the normals) in the right anterior inferior temporal cortex, the other (JG) in the right Broca's area, and both in the right frontal operculum. Although these differential right-hemisphere activations may have influenced the reading behavior of the patients, their activation patterns primarily reflect semantic and phonological systems in spared regions of the left hemisphere. These results preclude an explanation of deep dyslexia in terms of purely right-hemisphere word processing.

scholarly journals Neural Substrates Associated With Fatigue Symptom In Fibromyalgia

2022 ◽  
Author(s):  
Hung-Yu Liu ◽  
Pei-Lin Lee ◽  
Kun-Hsien Chou ◽  
Yen-Feng Wang ◽  
Shih-Pin Chen ◽  
...  
Keyword(s):  
Brain Mri ◽  
Temporal Cortex ◽  
Occipital Cortex ◽  
Neural Substrates ◽  
Inferior Temporal Cortex ◽  
Morphometry Analysis ◽  
Fatigue Severity ◽  
Subcortical Regions ◽  
The Right ◽  
Neural Signatures

Abstract Many patients with fibromyalgia (FM) experience fatigue, but the associated biological mechanisms have not been delineated. We aimed to investigate the neural signatures associated with fatigue severity in patients with FM using MRI. We consecutively recruited 138 patients with FM and collected their clinical profiles and brain-MRI data. We categorized the patients into 3 groups based on their fatigue severity. Using voxel-based morphometry analysis and trend analysis, we first identified neural structures showing volumetric changes associated with fatigue severity, and further explored their seed-to-voxel structural covariance networks (SCNs). Results showed decreased bilateral thalamic volumes were associated with higher severity of fatigue. There was a more widespread distribution of the thalamic SCNs to the frontal, parietal, subcortical, and limbic regions in patients with higher fatigue severity. In addition, increased right inferior temporal cortex volumes were associated with higher severity of fatigue. The right inferior temporal seed showed more SCNs distributions over the temporal cortex and a higher strength of SCNs to the bilateral occipital cortex in patients with higher fatigue severity. The thalamus and the right inferior temporal cortex as well as their altered interactions with cortical and subcortical regions comprise the neural signatures of fatigue in FM.

scholarly journals Sex differences in neural and behavioral signatures of cooperation revealed by fNIRS hyperscanning

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Joseph M. Baker ◽  
Ning Liu ◽  
Xu Cui ◽  
Pascal Vrticka ◽  
Manish Saggar ◽  
...  
Keyword(s):  
Sex Differences ◽  
Temporal Cortex ◽  
Neural Correlates ◽  
Behavioral Signatures ◽  
Computer Based ◽  
Males And Females ◽  
Brain And Behavior ◽  
The Right ◽  
And Behavior ◽  
The Brain

Abstract Researchers from multiple fields have sought to understand how sex moderates human social behavior. While over 50 years of research has revealed differences in cooperation behavior of males and females, the underlying neural correlates of these sex differences have not been explained. A missing and fundamental element of this puzzle is an understanding of how the sex composition of an interacting dyad influences the brain and behavior during cooperation. Using fNIRS-based hyperscanning in 111 same- and mixed-sex dyads, we identified significant behavioral and neural sex-related differences in association with a computer-based cooperation task. Dyads containing at least one male demonstrated significantly higher behavioral performance than female/female dyads. Individual males and females showed significant activation in the right frontopolar and right inferior prefrontal cortices, although this activation was greater in females compared to males. Female/female dyad’s exhibited significant inter-brain coherence within the right temporal cortex, while significant coherence in male/male dyads occurred in the right inferior prefrontal cortex. Significant coherence was not observed in mixed-sex dyads. Finally, for same-sex dyads only, task-related inter-brain coherence was positively correlated with cooperation task performance. Our results highlight multiple important and previously undetected influences of sex on concurrent neural and behavioral signatures of cooperation.

scholarly journals Distinct Neural Correlates of Linguistic and Non-Linguistic Demand

2021 ◽  
pp. 1-24
Author(s):  
Ian A. Quillen ◽  
Melodie Yen ◽  
Stephen M. Wilson
Keyword(s):  
Task Difficulty ◽  
Right Hemisphere ◽  
Semantic Network ◽  
Inferior Frontal Gyrus ◽  
Neural Correlates ◽  
Normal Individuals ◽  
Linguistic Demand ◽  
Neurologically Normal ◽  
The Right ◽  
Temporal Language

In this study, we investigated how the brain responds to task difficulty in linguistic and non-linguistic contexts. This is important for the interpretation of functional imaging studies of neuroplasticity in post-stroke aphasia, because of the inherent difficulty of matching or controlling task difficulty in studies with neurological populations. Twenty neurologically normal individuals were scanned with fMRI as they performed a linguistic task and a non-linguistic task, each of which had two levels of difficulty. Critically, the tasks were matched across domains (linguistic, non-linguistic) for accuracy and reaction time, such that the differences between the easy and difficult conditions were equivalent across domains. We found that non-linguistic demand modulated the same set of multiple demand (MD) regions that have been identified in many prior studies. In contrast, linguistic demand modulated MD regions to a much lesser extent, especially nodes belonging to the dorsal attention network. Linguistic demand modulated a subset of language regions, with the left inferior frontal gyrus most strongly modulated. The right hemisphere region homotopic to Broca’s area was also modulated by linguistic but not non-linguistic demand. When linguistic demand was mapped relative to non-linguistic demand, we also observed domain by difficulty interactions in temporal language regions as well as a widespread bilateral semantic network. In sum, linguistic and non-linguistic demand have strikingly different neural correlates. These findings can be used to better interpret studies of patients recovering from aphasia. Some reported activations in these studies may reflect task performance differences, while others can be more confidently attributed to neuroplasticity.

scholarly journals Localization of Syntactic and Semantic Brain Responses using Magnetoencephalography

2007 ◽  
Vol 19 (7) ◽  
pp. 1193-1205 ◽  
Author(s):  
Elisabet Service ◽  
Päivi Helenius ◽  
Sini Maury ◽  
Riitta Salmelin
Keyword(s):  
Temporal Lobe ◽  
Semantic Processing ◽  
Sentence Comprehension ◽  
Right Hemisphere ◽  
Temporal Cortex ◽  
Word Class ◽  
Sentence Reading ◽  
Word Onset ◽  
Semantic Errors ◽  
The Right

Electrophysiological methods have been used to study the temporal sequence of syntactic and semantic processing during sentence comprehension. Two responses associated with syntactic violations are the left anterior negativity (LAN) and the P600. A response to semantic violation is the N400. Although the sources of the N400 response have been identified in the left (and right) temporal lobe, the neural signatures of the LAN and P600 have not been revealed. The present study used magnetoencephalography to localize sources of syntactic and semantic activation in Finnish sentence reading. Participants were presented with sentences that ended in normally inf lected nouns, nouns in an unacceptable case, verbs instead of nouns, or nouns that were correctly inflected but made no sense in the context. Around 400 msec, semantically anomalous last words evoked strong activation in the left superior temporal lobe with significant activation also for word class errors (N400). Weaker activation was seen for the semantic errors in the right hemisphere. Later, 600-800 msec after word onset, the strongest activation was seen to word class and morphosyntactic errors (P600). Activation was significantly weaker to semantically anomalous and correct words. The P600 syntactic activation was localized to bilateral sources in the temporal lobe, posterior to the N400 sources. The results suggest that the same general region of the superior temporal cortex gives rise to both LAN and N400 with bilateral reactivity to semantic manipulation and a left hemisphere effect to syntactic manipulation. The bilateral P600 response was sensitive to syntactic but not semantic factors.

Categorizing and Individuating Others: The Neural Substrates of Person Perception

2004 ◽  
Vol 16 (10) ◽  
pp. 1785-1795 ◽  
Author(s):  
Malia F. Mason ◽  
C. Neil Macrae
Keyword(s):  
Neural Activity ◽  
Person Perception ◽  
Social Cognitive ◽  
Right Hemisphere ◽  
Neural Substrates ◽  
Hemispheric Differences ◽  
Cognitive Operations ◽  
Processing Abilities ◽  
Group Members ◽  
The Right

People are remarkably adroit at understanding other social agents. Quite how these information-processing abilities are realized, however, remains open to debate and empirical scrutiny. In particular, little is known about basic aspects of person perception, such as the operations that support people's ability to categorize (i.e., assign persons to groups) and individuate (i.e., discriminate among group members) others. In an attempt to rectify this situation, the current research focused on the initial perceptual stages of person construal and considered: (i) hemispheric differences in the efficiency of categorization and individuation; and (ii) the neural activity that supports these social-cognitive operations. Noting the greater role played by configural processing in individuation than categorization, it was expected that performance on the former task would be enhanced when stimuli (i.e., faces) were presented to the right rather than to the left cerebral hemisphere. The results of two experiments (Experiment 1—healthy individuals; Experiment 2—split-brain patient) confirmed this prediction. Extending these findings, a final neuroimaging investigation revealed that individuation is accompanied by neural activity in regions of the temporal and prefrontal cortices, especially in the right hemisphere. We consider the implications of these findings for contemporary treatments of person perception.

Neural Correlates of Mental State Decoding in Human Adults: An Event-related Potential Study

2004 ◽  
Vol 16 (3) ◽  
pp. 415-426 ◽  
Author(s):  
Mark A. Sabbagh ◽  
Margaret C. Moulson ◽  
Kate L. Harkness
Keyword(s):  
Theory Of Mind ◽  
Mental State ◽  
Right Hemisphere ◽  
Mental States ◽  
Neural Correlates ◽  
Event Related Potential ◽  
Neural Systems ◽  
Core Theory ◽  
Human Adults ◽  
The Right

Successful negotiation of human social interactions rests on having a theory of mind—an understanding of how others' behaviors can be understood in terms of internal mental states, such as beliefs, desires, intentions, and emotions. A core theory-of-mind skill is the ability to decode others' mental states on the basis of observable information, such as facial expressions. Although several recent studies have focused on the neural correlates of reasoning about mental states, no research has addressed the question of what neural systems underlie mental state decoding. We used dense-array eventrelated potentials (ERP) to show that decoding mental states from pictures of eyes is associated with an N270–400 component over inferior frontal and anterior temporal regions of the right hemisphere. Source estimation procedures suggest that orbitofrontal and medial temporal regions may underlie this ERP effect. These findings suggest that different components of everyday theory-of-mind skills may rely on dissociable neural mechanisms.

scholarly journals Medial Cortical Structures Mediate Implicit Trustworthiness Judgments about Kin Faces, but Not Familiar Faces: A Brief Report

Psych ◽  
2019 ◽  
Vol 1 (1) ◽  
pp. 482-490 ◽  
Author(s):  
Steven M. Platek ◽  
Judson C. Hendry
Keyword(s):  
Right Hemisphere ◽  
Kin Recognition ◽  
Insular Cortex ◽  
Neural Correlates ◽  
The Self ◽  
Anterior Cingulate ◽  
Dorsal Anterior Cingulate Cortex ◽  
Facial Stimuli ◽  
The Right ◽  
Processing Network

Human kin recognition activates substrates of the extended facial processing network, notably the right-hemisphere structures involved in self-face recognition and posterior medial cortical substrates. To understand the mechanisms underlying prosociality toward kin faces in comparison to other familiar faces, we investigated the neural correlates of implicit trustworthiness ratings to faces of actual kin and personal friends, controlling for activation to distracter faces. When controlling for activation associated with unknown faces, trustworthiness ratings of faces of kin, compared to friends, were associated with increased activation in the dorsal anterior cingulate cortex, posterior cingulate, and precuneous. On the other hand, trustworthiness ratings of friend faces, relative to kin faces, were associated with the lateral occipital gyrus and insular cortex. Trustworthiness ratings for unknown faces were only associated with activation in the fusiform gyrus. These findings suggest that we should employ medial cortical substrates known to be part of the self-other network when making implicit social judgements about kin, but not other classes of facial stimuli.

scholarly journals The rodent hippocampus as a bilateral structure: A review of hemispheric lateralization

2017 ◽  
Author(s):  
Jake T. Jordan
Keyword(s):  
Brain Region ◽  
Spatial Information ◽  
Right Hemisphere ◽  
Neural Substrates ◽  
Hemispheric Lateralization ◽  
Hemispheric Differences ◽  
Functional Lateralization ◽  
Left And Right ◽  
The Right ◽  
Behavior And Cognition

AbstractThe left and right rodent hippocampi exhibit striking lateralization in some of the very neural substrates considered to be critical for hippocampal cognitive function. Despite this, there is an overwhelming lack of consideration for hemispheric differences in studies of the rodent hippocampus. Asymmetries identified so far suggest that a bilateral model of the hippocampus will be essential for an understanding of this brain region, and perhaps of the brain more widely. Although hypotheses have been proposed to explain how the left and right hippocampi contribute to behavior and cognition, these hypotheses have either been refuted by more recent studies or have been limited in the scope of data they explain. Here, I will first review data on human and rodent hippocampal lateralization. The implications of these data suggest that considering the hippocampus as a bilateral structure with functional lateralization will be critical moving forward in understanding the function and mechanisms of this brain region. In exploring these implications, I will then propose a hypothesis of the hippocampus as a bilateral structure. This discrete-continuous (DC) hypothesis proposes that the left and right hippocampi contribute to spatial memory and navigation in a complementary manner. Specifically, the left hemisphere stores spatial information as discrete, salient locations and that the right hemisphere represents space continuously, contributing to route computation and flexible spatial navigation. Consideration of hippocampal lateralization in designing future studies may provide insight into the function of the hippocampus and resolve debates concerning its function.

scholarly journals Neurophysiological Subtypes of Depressive Disorders

Psychiatry ◽  
2021 ◽  
Vol 19 (2) ◽  
pp. 63-76
Author(s):  
I. A. Lapin ◽  
T. A. Rogacheva ◽  
A. A. Mitrofanov
Keyword(s):  
Depressive Disorders ◽  
Right Hemisphere ◽  
Temporal Cortex ◽  
Statistical Research ◽  
Atypical Depression ◽  
Leading Role ◽  
Gamma Coherence ◽  
Left And Right ◽  
The Right ◽  
Bipolar Affective Disorders

Background: the clinical polymorphism of depressive disorders, together with the available data on the different responses of patients to treatment, motivate modern neuroscience to search for models that can explain such heterogeneity.Objective: to identify neurophysiological subtypes of depressive disorders.Patients and methods: 189 patients with moderate depression in the structure of a depressive episode (n = 42), recurrent depressive (n = 102) and bipolar affective disorders (n = 45); 56 healthy subjects. Clinical-psychopathological, psychometric, neurophysiological and statistical research methods were used in the work.The results: with the help of coherent EEG analysis, it is possible to identify at least 6 subtypes of the disorder, which characterize various branches of the pathogenesis of affective pathology, which go beyond the currently accepted nomenclature. The selected subtypes were determined by the profi les of dysfunctional interaction of various cortical zones in the alpha, beta and gamma ranges of the EEG. Subtype 1 was characterized by a decrease relative to the norm of imaginary alpha-coherence between the right parietal and left central, right parietal and left anterior temporal, as well as the right parietal and right anterior temporal EEG leads (P4-C3, P4-F7, P4-F8) and explained part of depressions, in the pathogenesis of which the leading role was played by violations of the promotion of positive and suppression of negative affect. Subtype 2 — an increase in beta-2-imaginary-coherence between the frontal leads of the left and right hemispheres, between the left frontal and right central cortex (F3-F4; F3-C4) and its decrease between the central cortical zones (C4-C3), in clinical terms this subtype was characterized by a persistent hedonic response and was associated with the clinical picture of atypical depression. Subtype 3 — an increase in imaginary alpha-coherence between the frontal (F4-F3) and its decrease between the central leads of the left and right hemisphere (C4-C3), correlated with the severity of depressive rumination. Subtype 4 — a decrease in imaginary alpha-coherence between the anterior temporal and frontal, as well as the anterior temporal and central cortex of the right hemisphere (F8-F4 and F8-C4), explained part of the depressions that developed against the background of avoidance personality disorder. Subtype 5 — a decrease in imaginary gamma coherence between the frontal and parietal, as well as the central and occipital cortical zones of the left hemisphere (F3-P3 and C3-O1), was associated with an outwardly oriented utilitarian style of thinking (alexithymia). Subtype 6 — a decrease in imaginary beta-1 coherence between the left central and right anterior temporal cortex (C3-F8), explained part of the depression with phobic and hypochondriacal disorders in the structure of recurrent depressive disorder. Such a clinical and biological typology seems new and promising in terms of searching for specifi c neurophysiological disorders in different types of depression and, accordingly, reaching differentiated therapeutic recommendations.

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