scholarly journals Representation of motion concepts in occipitotemporal cortex: fMRI activation, decoding and connectivity analyses

2021 ◽  
Author(s):  
Yueyang Zhang ◽  
Rafael Lemarchand ◽  
Aliff Asyraff ◽  
Paul Hoffman
Keyword(s):  
Motion Perception ◽  
Semantic Processing ◽  
Brain Regions ◽  
Middle Part ◽  
Motion Events ◽  
Psychophysiological Interaction ◽  
Occipitotemporal Cortex ◽  
Multivariate Pattern ◽  
Level Performance ◽  
Univariate Analyses

Embodied theories of semantic cognition predict that brain regions involved in motion perception are engaged when people comprehend motion concepts expressed in language. Left lateral occipitotemporal cortex (LOTC) is implicated in both motion perception and motion concept processing but prior studies have produced mixed findings regarding which parts of this region are engaged by motion language. We scanned participants performing semantic judgements about sentences describing motion events and static events. We performed univariate analyses, multivariate pattern analyses (MVPA) and psychophysiological interaction (PPI) analyses to investigate the effect of motion on activity and connectivity in different parts of LOTC. In multivariate analyses that decoded whether a sentence described motion or not, the whole of LOTC showed above-chance level performance, with performance exceeding that of other brain regions. Univariate ROI analyses found that the middle part of LOTC was more active for motion events than static ones. Finally, PPI analyses found that when processing motion events, the middle and posterior parts of LOTC, overlapping with motion perception regions, increased their connectivity with cognitive control regions. Taken together, these results indicate that the whole of the LOTC responds differently to motion vs. static event descriptions, and that these effects are most pronounced in more posterior sites. These findings are consistent with embodiment accounts of semantic processing, and suggest that understanding verbal descriptions of motion engages areas of the occipitotemporal cortex involved in perceiving motion.

scholarly journals Taste quality representation in the human brain

2019 ◽  
Author(s):  
Jason A. Avery ◽  
Alexander G. Liu ◽  
John E. Ingeholm ◽  
Cameron D. Riddell ◽  
Stephen J. Gotts ◽  
...  
Keyword(s):  
Human Brain ◽  
Cortical Neurons ◽  
Brain Regions ◽  
Taste Quality ◽  
7 Tesla ◽  
Mammalian Brain ◽  
High Magnetic Field Strength ◽  
Magnetic Resonance Imaging Mri ◽  
Spatial Locations ◽  
Univariate Analyses

SUMMARYIn the mammalian brain, the insula is the primary cortical substrate involved in the perception of taste. Recent imaging studies in rodents have identified a gustotopic organization in the insula, whereby distinct insula regions are selectively responsive to one of the five basic tastes. However, numerous studies in monkeys have reported that gustatory cortical neurons are broadly-tuned to multiple tastes, and tastes are not represented in discrete spatial locations. Neuroimaging studies in humans have thus far been unable to discern between these two models, though this may be due to the relatively low spatial resolution employed in taste studies to date. In the present study, we examined the spatial representation of taste within the human brain using ultra-high resolution functional magnetic resonance imaging (MRI) at high magnetic field strength (7-Tesla). During scanning, participants tasted sweet, salty, sour and tasteless liquids, delivered via a custom-built MRI-compatible tastant-delivery system. Our univariate analyses revealed that all tastes (vs. tasteless) activated primary taste cortex within the bilateral dorsal mid-insula, but no brain region exhibited a consistent preference for any individual taste. However, our multivariate searchlight analyses were able to reliably decode the identity of distinct tastes within those mid-insula regions, as well as brain regions involved in affect and reward, such as the striatum, orbitofrontal cortex, and amygdala. These results suggest that taste quality is not represented topographically, but by a combinatorial spatial code, both within primary taste cortex as well as regions involved in processing the hedonic and aversive properties of taste.

Neurocircuitries of Emotion Processing Affected in Major Depressive Disorder

2019 ◽  
pp. 101-114
Author(s):  
Anjali Sankar ◽  
Cynthia H.Y. Fu
Keyword(s):  
Major Depression ◽  
Predictive Accuracy ◽  
Emotion Processing ◽  
Affective State ◽  
Brain Regions ◽  
First Episode ◽  
Neuroimaging Data ◽  
Multivariate Pattern ◽  
Future Work ◽  
Hallmark Feature

Impairments in processing emotions are a hallmark feature of depression. Advances in neuroimaging techniques have rapidly improved our understanding of the pathophysiology underlying major depression. In this chapter, we provide an overview of influential neural models of emotion perception and regulation and discuss the neurocircuitries of emotion processing that are affected. Major depression is characterized by impairments in widespread brain regions that are evident in the first episode. Models have sought to distinguish the neural circuitry associated with recognition of the emotion, integration of somatic responses, and monitoring of the affective state. In particular, there has been a preponderance of research on the neurocircuitries affected during processing of mood-congruent negative emotional stimuli in depression. While neuroimaging correlates have been investigated and models proposed, these findings have had limited clinical applicability to date. Novel methods such as multivariate pattern recognition applied to neuroimaging data might enable identification of reliable, valid, and robust biomarkers with high predictive accuracy that can be applied to an individual. Last, we discuss avenues for extension and future work.

scholarly journals Disentangling Representations of Object Shape and Object Category in Human Visual Cortex: The Animate–Inanimate Distinction

2016 ◽  
Vol 28 (5) ◽  
pp. 680-692 ◽  
Author(s):  
Daria Proklova ◽  
Daniel Kaiser ◽  
Marius V. Peelen
Keyword(s):  
Visual Cortex ◽  
Activity Patterns ◽  
Temporal Cortex ◽  
Brain Regions ◽  
Visual Object ◽  
Object Category ◽  
Human Visual Cortex ◽  
Object Properties ◽  
Occipitotemporal Cortex ◽  
Visual Properties

Objects belonging to different categories evoke reliably different fMRI activity patterns in human occipitotemporal cortex, with the most prominent distinction being that between animate and inanimate objects. An unresolved question is whether these categorical distinctions reflect category-associated visual properties of objects or whether they genuinely reflect object category. Here, we addressed this question by measuring fMRI responses to animate and inanimate objects that were closely matched for shape and low-level visual features. Univariate contrasts revealed animate- and inanimate-preferring regions in ventral and lateral temporal cortex even for individually matched object pairs (e.g., snake–rope). Using representational similarity analysis, we mapped out brain regions in which the pairwise dissimilarity of multivoxel activity patterns (neural dissimilarity) was predicted by the objects' pairwise visual dissimilarity and/or their categorical dissimilarity. Visual dissimilarity was measured as the time it took participants to find a unique target among identical distractors in three visual search experiments, where we separately quantified overall dissimilarity, outline dissimilarity, and texture dissimilarity. All three visual dissimilarity structures predicted neural dissimilarity in regions of visual cortex. Interestingly, these analyses revealed several clusters in which categorical dissimilarity predicted neural dissimilarity after regressing out visual dissimilarity. Together, these results suggest that the animate–inanimate organization of human visual cortex is not fully explained by differences in the characteristic shape or texture properties of animals and inanimate objects. Instead, representations of visual object properties and object category may coexist in more anterior parts of the visual system.

Integrated Contextual Representation for Objects' Identities and Their Locations

2008 ◽  
Vol 20 (3) ◽  
pp. 371-388 ◽  
Author(s):  
Nurit Gronau ◽  
Maital Neta ◽  
Moshe Bar
Keyword(s):  
Object Recognition ◽  
Semantic Processing ◽  
Contextual Information ◽  
Reaction Times ◽  
Brain Regions ◽  
Target Object ◽  
Interactive Effects ◽  
Attention And Memory ◽  
Contextual Knowledge ◽  
Lateral Occipital Complex

Visual context plays a prominent role in everyday perception. Contextual information can facilitate recognition of objects within scenes by providing predictions about objects that are most likely to appear in a specific setting, along with the locations that are most likely to contain objects in the scene. Is such identity-related (“semantic”) and location-related (“spatial”) contextual knowledge represented separately or jointly as a bound representation? We conducted a functional magnetic resonance imaging (fMRI) priming experiment whereby semantic and spatial contextual relations between prime and target object pictures were independently manipulated. This method allowed us to determine whether the two contextual factors affect object recognition with or without interacting, supporting a unified versus independent representations, respectively. Results revealed a Semantic × Spatial interaction in reaction times for target object recognition. Namely, significant semantic priming was obtained when targets were positioned in expected (congruent), but not in unexpected (incongruent), locations. fMRI results showed corresponding interactive effects in brain regions associated with semantic processing (inferior prefrontal cortex), visual contextual processing (parahippocampal cortex), and object-related processing (lateral occipital complex). In addition, activation in fronto-parietal areas suggests that attention and memory-related processes might also contribute to the contextual effects observed. These findings indicate that object recognition benefits from associative representations that integrate information about objects' identities and their locations, and directly modulate activation in object-processing cortical regions. Such context frames are useful in maintaining a coherent and meaningful representation of the visual world, and in providing a platform from which predictions can be generated to facilitate perception and action.

The Components of Vestibular Cognition — Motion Versus Spatial Perception

2015 ◽  
Vol 28 (5-6) ◽  
pp. 507-524 ◽  
Author(s):  
Barry M. Seemungal
Keyword(s):  
Motion Perception ◽  
Spatial Orientation ◽  
Spatial Perception ◽  
Brain Regions ◽  
Motion Processing ◽  
Research Activity ◽  
Ocular Reflex ◽  
Vestibular Ocular Reflex ◽  
Optimal Functioning ◽  
Self Motion

Vestibular cognition can be divided into two main functions — a primary vestibular sensation of self-motion and a derived sensation of spatial orientation. Although the vestibular system requires calibration from other senses for optimal functioning, both vestibular spatial and vestibular motion perception are typically employed when navigating without vision. A recent important finding is the cerebellar mediation of the uncoupling of reflex (i.e., the vestibular-ocular reflex) from vestibular motion perception (Perceptuo-Reflex Uncoupling). The brain regions that mediate vestibular motion and vestibular spatial perception is an area of on-going research activity. However, there is data to support the notion that vestibular motion perception is mediated by multiple brain regions. In contrast, vestibular spatial perception appears to be mediated by posterior brain areas although currently the exact locus is unclear. I will discuss the experimental evidence that support this functional dichotomy in vestibular cognition (i.e., motion processingvs.spatial orientation). Along the way I will highlight relevant practical technical tips in testing vestibular cognition.

scholarly journals What’s “up”? Impaired Spatial Preposition Processing in Posterior Cortical Atrophy

2021 ◽  
Vol 15 ◽  
Author(s):  
Zubaida Shebani ◽  
Peter J. Nestor ◽  
Friedemann Pulvermüller
Keyword(s):  
Serial Recall ◽  
Semantic Processing ◽  
Memory Performance ◽  
Strong Support ◽  
Case Series ◽  
Brain Regions ◽  
Cortical Atrophy ◽  
Posterior Cortical Atrophy ◽  
Atypical Form ◽  
Spatial Prepositions

This study seeks to confirm whether lesions in posterior regions of the brain involved in visuo-spatial processing are of functional relevance to the processing of words with spatial meaning. We investigated whether patients with Posterior Cortical Atrophy (PCA), an atypical form of Alzheimer’s Disease which predominantly affects parieto-occipital brain regions, is associated with deficits in working memory for spatial prepositions. Case series of patients with PCA and matched healthy controls performed tests of immediate and delayed serial recall on words from three lexico-semantic word categories: number words (twelve), spatial prepositions (behind) and function words (e.g., shall). The three word categories were closely matched for a number of psycholinguistic and semantic variables including length, bi-/tri-gram frequency, word frequency, valence and arousal. Relative to controls, memory performance of PCA patients on short word lists was significantly impaired on spatial prepositions in the delayed serial recall task. These results suggest that lesions in posterior parieto-occipital regions specifically impair the processing of spatial prepositions. Our findings point to a pertinent role of posterior cortical regions in the semantic processing of words with spatial meaning and provide strong support for modality-specific semantic theories that recognize the necessary contributions of sensorimotor regions to conceptual semantic processing.

scholarly journals Neural substrates for moral judgments of psychological versus physical harm

2017 ◽  
Author(s):  
Lily Tsoi ◽  
James A Dungan ◽  
Alek Chakroff ◽  
Liane Young
Keyword(s):  
Theory Of Mind ◽  
Psychological Impact ◽  
Brain Regions ◽  
Autism Spectrum ◽  
Moral Judgments ◽  
Anterior Cingulate ◽  
Adults With Autism ◽  
Temporoparietal Junction ◽  
The Right ◽  
Multivariate Pattern

Although harm primarily elicits thoughts of physical injuries, harm can also take the form of negative psychological impact. Using functional magnetic resonance imaging (fMRI), we examined the extent to which moral judgments of physical and psychological harms are processed similarly, focusing on brain regions implicated in mental state reasoning or theory of mind, a key cognitive process for moral judgment. Univariate analyses reveal similar levels of theory of mind processing for psychological and physical harms, though multivariate pattern analyses (MVPA) reveal sensitivity to the psychological/physical distinction in two regions implicated in theory of mind: the right temporoparietal junction and the precuneus. Moreover, while there were no differences in neurotypical adults and adults with autism spectrum disorder with regard to neural activity related to theory of mind, there was a group difference in the recruitment of the anterior cingulate cortex for psychological versus physical harms. Altogether, these results reveal sensitivity within regions implicated in theory of mind to the physical / psychological distinction as well as neural processes that capture clinically relevant differences in evaluations of psychological harms versus physical harms.

scholarly journals A heuristic feature cluster search algorithm for precise functional brain mapping

2019 ◽  
Author(s):  
Nima Asadi ◽  
Yin Wang ◽  
Ingrid Olson ◽  
Zoran Obradovic
Keyword(s):  
Pattern Analysis ◽  
Search Algorithm ◽  
Search Space ◽  
Brain Regions ◽  
Information Value ◽  
Multivariate Pattern Analysis ◽  
Functional Brain Mapping ◽  
Optimization Parameters ◽  
Synthetic Datasets ◽  
Multivariate Pattern

ABSTRACTDetecting the most relevant brain regions for explaining the distinction between cognitive conditions is one of the most sought after objectives in neuroimaging research. A popular approach for achieving this goal is the multivariate pattern analysis (MVPA) which is commonly conducted through the searchlight procedure as well as a number of other approaches. This is due to advantages of such methods which include being intuitive and flexible with regards to size of the search space. However, these approaches suffer from a number of limitations that lead to misidentification of truly informative voxels or clusters of voxels which in turn results in imprecise information maps. The limitations of such procedures mainly stem from several factors such as the fact that the information value of the search spheres are assigned to the voxel at the center of them (in case of searchlight), the requirement for manual tuning of parameters such as searchlight radius and shape and other optimization parameters, overlooking the structure and interactions within the regions, and the drawbacks of using regularization methods in analysis of datasets with characteristics of common fMRI data. In this paper, we propose a fully data-driven maximum relevance minimum redundancy search algorithm for detecting precise information value of voxel-level clusters within brain regions while alleviating the above mentioned limitations. In order to make the algorithm efficient, we propose an implementation based on principles of dynamic programming. We evaluate and compare the proposed algorithm with the searchlight procedure using both real and synthetic datasets.

The Fusiform and Occipital Face Areas Can Process a Nonface Category Equivalently to Faces

2018 ◽  
Vol 30 (10) ◽  
pp. 1499-1516 ◽  
Author(s):  
Valentinos Zachariou ◽  
Zaid N. Safiullah ◽  
Leslie G. Ungerleider
Keyword(s):  
Face Perception ◽  
Spatial Configuration ◽  
Cognitive Strategies ◽  
Brain Regions ◽  
The Other ◽  
Behavioral Performance ◽  
Ongoing Debate ◽  
Present Evidence ◽  
Object Categories ◽  
Occipitotemporal Cortex

The fusiform and occipital face areas (FFA and OFA) are functionally defined brain regions in human ventral occipitotemporal cortex associated with face perception. There is an ongoing debate, however, whether these regions are face-specific or whether they also facilitate the perception of nonface object categories. Here, we present evidence that, under certain conditions, bilateral FFA and OFA respond to a nonface category equivalently to faces. In two fMRI sessions, participants performed same–different judgments on two object categories (faces and chairs). In one session, participants differentiated between distinct exemplars of each category, and in the other session, participants differentiated between exemplars that differed only in the shape or spatial configuration of their features (featural/configural differences). During the latter session, the within-category similarity was comparable for both object categories. When differentiating between distinct exemplars of each category, bilateral FFA and OFA responded more strongly to faces than to chairs. In contrast, during featural/configural difference judgments, bilateral FFA and OFA responded equivalently to both object categories. Importantly, during featural/configural difference judgments, the magnitude of activity within FFA and OFA evoked by the chair task predicted the participants' behavioral performance. In contrast, when participants differentiated between distinct chair exemplars, activity within these face regions did not predict the behavioral performance of the chair task. We conclude that, when the within-category similarity of a face and a nonface category is comparable and when the same cognitive strategies used to process a face are applied to a nonface category, the FFA and OFA respond equivalently to that nonface category and faces.

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