Cerebral Cortical Representation of Automatic and Volitional Swallowing in Humans

Although the cerebral cortex has been implicated in the control of swallowing, the functional organization of the human cortical swallowing representation has not been fully documented. Therefore, the present study determined the cortical representation of swallowing in fourteen healthy right-handed female subjects using single-event-related functional magnetic resonance imaging (fMRI). Subjects were scanned during three swallowing activation tasks: a naı̈ve saliva swallow, a voluntary saliva swallow, and a water bolus swallow. Swallow-related laryngeal movement was recorded simultaneously from the output of a bellows positioned over the thyroid cartilage. Statistical maps were generated by computing the difference between the magnitude of the voxel time course during 1) a single swallowing trial and 2) the corresponding control period. Automatic and volitional swallowing produced activation within several common cortical regions, the most prominent and consistent being located within the lateral precentral gyrus, lateral postcentral gyrus, and right insula. Activation foci within the superior temporal gyrus, middle and inferior frontal gyri, and frontal operculum also were identified for all swallowing tasks. In contrast, activation of the caudal anterior cingulate cortex was significantly more likely in association with the voluntary saliva swallow and water bolus swallow than the naı̈ve swallow. These findings support the view that, in addition to known brain stem areas, human swallowing is represented within a number of spatially and functionally distinct cortical loci which may participate differentially in the regulation of swallowing. Activation of the insula was significantly lateralized to the right hemisphere for the voluntary saliva swallow, suggesting a functional hemispheric dominance of the insula for the processing of swallowing.

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Sensory perception in autism: an fMRI ALE meta-analysis

10.31234/osf.io/p9n2z ◽

2020 ◽

Author(s):

Nazia Jassim ◽

Simon Baron-Cohen ◽

John Suckling

Keyword(s):

Meta Analysis ◽

Likelihood Estimation ◽

Sensory Perception ◽

Superior Temporal Gyrus ◽

Occipital Cortex ◽

Anterior Cingulate ◽

Future Research ◽

Precentral Gyrus ◽

And Control ◽

Lateral Occipital Cortex

Sensory sensitivities occur in up to 90% of autistic individuals. With the recent inclusion of sensory symptoms in the diagnostic criteria for autism, there is a current need to develop neural hypotheses related to autistic sensory perception. Using activation likelihood estimation (ALE), we meta-analysed 52 task-based fMRI studies investigating differences between autistic (n=891) and control (n=967) participants during non-social sensory perception. During complex perception, autistic groups showed more activity in the secondary somatosensory and occipital cortices, insula, caudate, superior temporal gyrus, and inferior parietal lobule, while control groups showed more activity in the frontal and parietal regions. During basic sensory processing, autistic groups showed hyperactivity in the lateral occipital cortex, primary somatosensory and motor cortices, insula, caudate, and thalamus, while controls showed heightened activity in the precentral gyrus, middle frontal gyrus, precuneus, and anterior cingulate cortex. We conclude that autistic individuals, on average, show distinct engagement of sensory-related brain networks during sensory perception. These findings may help guide future research to focus on relevant neurobiological mechanisms underpinning the autistic experience.

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Homotopic organization of essential language sites in right and bilateral cerebral hemispheric dominance

Journal of Neurosurgery ◽

10.3171/2010.11.jns10888 ◽

2011 ◽

Vol 114 (4) ◽

pp. 893-902 ◽

Cited By ~ 38

Author(s):

Edward F. Chang ◽

Doris D. Wang ◽

David W. Perry ◽

Nicholas M. Barbaro ◽

Mitchel S. Berger

Keyword(s):

San Francisco ◽

Left Hemisphere ◽

Language Production ◽

Right Hemisphere ◽

General Pattern ◽

Hemispheric Dominance ◽

Precentral Gyrus ◽

Language Dominance ◽

Speech Mapping ◽

Hemisphere Dominance

Object Language dominance in the right hemisphere is rare. Therefore, the organization of essential language sites in the dominant right hemisphere is unclear, especially compared with cases involving the more prevalent left dominant hemisphere. Methods The authors reviewed the medical records of 15 patients who underwent awake craniotomy for tumor or epilepsy surgery and speech mapping of right hemisphere perisylvian language areas at the University of California, San Francisco. All patients were determined to have either complete right-sided or bilateral language dominance by preoperative Wada testing. Results All patients but one were left-handed. Of more than 331 total stimulation sites, 27 total sites were identified as essential for language function (14 sites for speech arrest/anarthria; 12 for anomia; and 1 for alexia). While significant interindividual variability was observed, the general pattern of language organization was similar to classic descriptions of frontal language production and posterior temporal language integration for the left hemisphere. Speech arrest sites were clustered in the ventral precentral gyrus and pars opercularis. Anomia sites were more widely distributed, but were focused in the posterior superior and middle temporal gyri as well as the inferior parietal gyrus. One alexia site was found over the superior temporal gyrus. Face sensory and motor cortical sites were also identified along the ventral sensorimotor strip. The prevalence and specificity of essential language sites were greater in unilateral right hemisphere–dominant patients, compared with those with bilateral dominance by Wada testing. Conclusions The authors' results suggest that the organization of language in right hemisphere dominance mirrors that of left hemisphere dominance. Awake speech mapping is a safe and reliable surgical adjunct in these rare clinical cases and should be done in the setting of right hemisphere dominance to avoid preventable postoperative aphasia.

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Resting-State Functional Connectivity of the Thalamus in Complete Spinal Cord Injury

Neurorehabilitation and Neural Repair ◽

10.1177/1545968319893299 ◽

2020 ◽

Vol 34 (2) ◽

pp. 122-133

Author(s):

Keerthana Deepti Karunakaran ◽

Rui Yuan ◽

Jie He ◽

Jian Zhao ◽

Jian-Ling Cui ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Functional Connectivity ◽

Resting State ◽

Functional Organization ◽

Superior Temporal Gyrus ◽

Anterior Cingulate ◽

Connectivity Analysis ◽

Cord Injury ◽

Ventrolateral Nucleus

Background. Neuroimaging studies of spinal cord injury (SCI) have mostly examined the functional organization of the cortex, with only limited focus on the subcortical substrates of the injury. However, thalamus is an important modulator and sensory relay that requires investigation at a subnuclei level to gain insight into the neuroplasticity following SCI. Objective. To use resting-state functional magnetic resonance imaging to examine the functional connectivity (FC) of thalamic subnuclei in complete SCI patients. Methods. A seed-based connectivity analysis was applied for 3 thalamic subnuclei: pulvinar, mediodorsal, and ventrolateral nucleus in each hemisphere. A nonparametric 2-sample t test with permutations was applied for each of the 6 thalamic seeds to compute FC differences between 22 healthy controls and 19 complete SCI patients with paraplegia. Results. Connectivity analysis showed a decrease in the FC of the bilateral mediodorsal nucleus with right superior temporal gyrus and anterior cingulate cortex in the SCI group. Similarly, the left ventrolateral nucleus exhibited decreased FC with left superior temporal gyrus in SCI group. In contrast, left pulvinar nucleus demonstrated an increase in FC with left inferior frontal gyrus and left inferior parietal lobule in SCI group. Our findings also indicate a negative relationship between postinjury durations and thalamic FC to regions of sensorimotor and visual cortices, where longer postinjury durations (~12 months) is associated with higher negative connectivity between these regions. Conclusion. This study provides evidence for reorganization in the thalamocortical connections known to be involved in multisensory integration and affective processing, with possible implications in the generation of sensory abnormalities after SCI.

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A short review on emotion processing: a lateralized network of neuronal networks

Brain Structure and Function ◽

10.1007/s00429-021-02331-7 ◽

2021 ◽

Author(s):

Nicola Palomero-Gallagher ◽

Katrin Amunts

Keyword(s):

Large Scale ◽

Neuronal Networks ◽

Dynamic Models ◽

Right Hemisphere ◽

Hemispheric Specialization ◽

Emotion Processing ◽

Anterior Cingulate ◽

Hemispheric Dominance ◽

The Right ◽

External Stimuli

AbstractEmotions are valenced mental responses and associated physiological reactions that occur spontaneously and automatically in response to internal or external stimuli, and can influence our behavior, and can themselves be modulated to a certain degree voluntarily or by external stimuli. They are subserved by large-scale integrated neuronal networks with epicenters in the amygdala and the hippocampus, and which overlap in the anterior cingulate cortex. Although emotion processing is accepted as being lateralized, the specific role of each hemisphere remains an issue of controversy, and two major hypotheses have been proposed. In the right-hemispheric dominance hypothesis, all emotions are thought to be processed in the right hemisphere, independent of their valence or of the emotional feeling being processed. In the valence lateralization hypothesis, the left is thought to be dominant for the processing of positively valenced stimuli, or of stimuli inducing approach behaviors, whereas negatively valenced stimuli, or stimuli inducing withdrawal behaviors, would be processed in the right hemisphere. More recent research points at the existence of multiple interrelated networks, each associated with the processing of a specific component of emotion generation, i.e., its generation, perception, and regulation. It has thus been proposed to move from hypotheses supporting an overall hemispheric specialization for emotion processing toward dynamic models incorporating multiple interrelated networks which do not necessarily share the same lateralization patterns.

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The Precentral Gyrus Contributions to the Early Time-Course of Grapheme-to-Phoneme Conversion

Neurobiology of Language ◽

10.1162/nol_a_00047 ◽

2021 ◽

pp. 1-61

Author(s):

Erik Kaestner ◽

Xiaojing Wu ◽

Daniel Friedman ◽

Patricia Dugan ◽

Orrin Devinsky ◽

...

Keyword(s):

Letter String ◽

Time Course ◽

Phase Locking ◽

Silent Reading ◽

Early Time ◽

Superior Temporal Gyrus ◽

Precentral Gyrus ◽

High Concentration ◽

High Gamma ◽

Pars Opercularis

Abstract As part of silent reading models, visual orthographic information is transduced into an auditory phonological code in a process of grapheme-to-phoneme conversion (GPC). This process is often identified with lateral temporal-parietal regions associated with auditory phoneme encoding. However, the role of articulatory phonemic representations and the precentral gyrus in GPC is ambiguous. Though the precentral gyrus is implicated in many functional MRI studies of reading, it is not clear if the time course of activity in this region is consistent with the precentral gyrus being involved in GPC. We recorded cortical electrophysiology during a bimodal match/mismatch task from eight patients with perisylvian subdural electrodes to examine the time course of neural activity during a task which necessitated GPC. Patients made a match/mismatch decision between a three-letter string and the following auditory bi-phoneme. We characterized the distribution and timing of evoked broadband high gamma (BHG; 70–170 Hz) as well as phase-locking between electrodes. The precentral gyrus emerged with a high concentration of broadband high gamma responses to visual and auditory language as well as mismatch effects. The pars opercularis, supramarginal gyrus, and superior temporal gyrus were also involved. The precentral gyrus showed strong phase-locking with the caudal fusiform gyrus during letter-string presentation and with surrounding perisylvian cortex during the bimodal visual-auditory comparison period. These findings hint at a role for precentral cortex in transducing visual into auditory codes during silent reading.

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An exploratory study of the neural mechanisms of decision making in compulsive hoarding

Psychological Medicine ◽

10.1017/s0033291708003371 ◽

2008 ◽

Vol 39 (2) ◽

pp. 325-336 ◽

Cited By ~ 81

Author(s):

D. F. Tolin ◽

K. A. Kiehl ◽

P. Worhunsky ◽

G. A. Book ◽

N. Maltby

Keyword(s):

Decision Making ◽

Superior Temporal Gyrus ◽

Anterior Cingulate ◽

Parahippocampal Gyrus ◽

Middle Temporal Gyrus ◽

Precentral Gyrus ◽

Compulsive Hoarding ◽

Experimental Psychopathology ◽

Compulsive Disorder ◽

Neural Underpinnings

BackgroundPrior studies have suggested unique patterns of neural activity associated with compulsive hoarding. However, to date no studies have examined the process of making actual decisions about whether to keep or discard possessions in patients with hoarding symptoms. An increasing body of clinical data and experimental psychopathology research suggests that hoarding is associated with impaired decision making; therefore, it is important to understand the neural underpinnings of decision-making abnormalities in hoarding patients.MethodTwelve adult patients diagnosed with compulsive hoarding, 17% of whom also met criteria for obsessive–compulsive disorder (OCD), and 12 matched healthy controls underwent functional magnetic resonance imaging (fMRI) while making decisions about whether or not to discard personal paper items (e.g. junk mail) brought to the laboratory as well as control items that did not belong to them. Items were either saved or destroyed following each decision.ResultsWhen deciding about whether to keep or discard personal possessions, compulsive hoarding participants displayed excessive hemodynamic activity in lateral orbitofrontal cortex and parahippocampal gyrus. Among hoarding participants, decisions to keep personal possessions were associated with greater activity in superior temporal gyrus, middle temporal gyrus, medial frontal gyrus, anterior cingulate cortex, precentral gyrus, and cerebellum than were decisions to discard personal possessions.ConclusionsThese results provide partial support for an emerging model of compulsive hoarding based on complications of the decision-making process. They also suggest that compulsive hoarding may be characterized by focal deficits in the processing of reward and changes in reward contingencies, particularly when these are perceived to be punishing.

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Brain capillary structures of schizophrenia cases and controls show a correlation with their neuron structures

Scientific Reports ◽

10.1038/s41598-021-91233-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Rino Saiga ◽

Masayuki Uesugi ◽

Akihisa Takeuchi ◽

Kentaro Uesugi ◽

Yoshio Suzuki ◽

...

Keyword(s):

Blood Vessels ◽

Structural Parameters ◽

Three Dimensional ◽

Superior Temporal Gyrus ◽

Anterior Cingulate ◽

Dimensional Structure ◽

Constant Diameter ◽

The Mean ◽

Cartesian Coordinate ◽

Micrometer Scale

AbstractBrain blood vessels constitute a micrometer-scale vascular network responsible for supply of oxygen and nutrition. In this study, we analyzed cerebral tissues of the anterior cingulate cortex and superior temporal gyrus of schizophrenia cases and age/gender-matched controls by using synchrotron radiation microtomography or micro-CT in order to examine the three-dimensional structure of cerebral vessels. Over 1 m of cerebral blood vessels was traced to build Cartesian-coordinate models, which were then used for calculating structural parameters including the diameter and curvature of the vessels. The distribution of vessel outer diameters showed a peak at 7–9 μm, corresponding to the diameter of the capillaries. Mean curvatures of the capillary vessels showed a significant correlation to the mean curvatures of neurites, while the mean capillary diameter was almost constant, independent of the cases. Our previous studies indicated that the neurites of schizophrenia cases are thin and tortuous compared to controls. The curved capillaries with a constant diameter should occupy a nearly constant volume, while neurons suffering from neurite thinning should have reduced volumes, resulting in a volumetric imbalance between the neurons and the vessels. We suggest that the observed structural correlation between neurons and blood vessels is related to neurovascular abnormalities in schizophrenia.

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Anhedonia in Semantic Dementia—Exploring Right Hemispheric Contributions to the Loss of Pleasure

Brain Sciences ◽

10.3390/brainsci11080998 ◽

2021 ◽

Vol 11 (8) ◽

pp. 998

Author(s):

Siobhán R. Shaw ◽

Hashim El-Omar ◽

Siddharth Ramanan ◽

Olivier Piguet ◽

Rebekah M. Ahmed ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Temporal Lobe ◽

Rating Scale ◽

Right Hemisphere ◽

Semantic Knowledge ◽

Semantic Dementia ◽

Anterior Cingulate ◽

Functional Impairments ◽

Lobe Atrophy

Semantic dementia (SD) is a younger-onset neurodegenerative disease characterised by progressive deterioration of the semantic knowledge base in the context of predominantly left-lateralised anterior temporal lobe (ATL) atrophy. Mounting evidence indicates the emergence of florid socioemotional changes in SD as atrophy encroaches into right temporal regions. How lateralisation of temporal lobe pathology impacts the hedonic experience in SD remains largely unknown yet has important implications for understanding socioemotional and functional impairments in this syndrome. Here, we explored how lateralisation of temporal lobe atrophy impacts anhedonia severity on the Snaith–Hamilton Pleasure Scale in 28 SD patients presenting with variable right- (SD-R) and left-predominant (SD-L) profiles of temporal lobe atrophy compared to that of 30 participants with Alzheimer’s disease and 30 healthy older Control participants. Relative to Controls, SD-R but not SD-L or Alzheimer’s patients showed clinically significant anhedonia, representing a clear departure from premorbid levels. Overall, anhedonia was more strongly associated with functional impairment on the Frontotemporal Dementia Functional Rating Scale and motivational changes on the Cambridge Behavioural Inventory in SD than in Alzheimer’s disease patients. Voxel-based morphometry analyses revealed that anhedonia severity correlated with reduced grey matter intensity in a restricted set of regions centred on right orbitofrontal and temporopolar cortices, bilateral posterior temporal cortices, as well as the anterior cingulate gyrus and parahippocampal gyrus, bilaterally. Finally, regression and mediation analysis indicated a unique role for right temporal lobe structures in modulating anhedonia in SD. Our findings suggest that degeneration of predominantly right-hemisphere structures deleteriously impacts the capacity to experience pleasure in SD. These findings offer important insights into hemispheric lateralisation of motivational disturbances in dementia and suggest that anhedonia may emerge at different timescales in the SD disease trajectory depending on the integrity of the right hemisphere.

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Provocation and prediction of visual peripersonal neglect-like symptoms in preoperative planning and during awake brain surgery

Acta Neurochirurgica ◽

10.1007/s00701-021-04822-2 ◽

2021 ◽

Author(s):

Viktória Tamás ◽

Gabriella Sebestyén ◽

Szilvia Anett Nagy ◽

Péter Zsolt Horváth ◽

Ákos Mérei ◽

...

Keyword(s):

Preoperative Planning ◽

Right Hemisphere ◽

Superior Temporal Gyrus ◽

Low Grade ◽

Navigated Transcranial Magnetic Stimulation ◽

Resonance Imaging ◽

Parietal Area ◽

Routine Magnetic Resonance Imaging ◽

Visuospatial Functions ◽

The Right

AbstractNeglect is a severe neuropsychological/neurological deficit that usually develops due to lesions of the posterior inferior parietal area of the right hemisphere and is characterized by a lack of attention to the left side. Our case is a proven right-handed, 30-year-old female patient with a low-grade glioma, which was located in the temporo-opercular region and also in the superior temporal gyrus of the right hemisphere. Upon presurgical planning, the motor, language, and visuospatial functions were mapped. In order to achieve this, the protocol for routine magnetic resonance imaging and navigated transcranial magnetic stimulation has been expanded, accordingly.

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Is Lateropulsion Really Related with a Specific Lesion of the Brain?

Brain Sciences ◽

10.3390/brainsci11030354 ◽

2021 ◽

Vol 11 (3) ◽

pp. 354

Author(s):

Kyoung Lee ◽

Sang Yoo ◽

Eun Ji ◽

Woo Hwang ◽

Yeun Yoo ◽

...

Keyword(s):

Right Hemisphere ◽

Parietal Lobe ◽

Inferior Frontal Gyrus ◽

Brain Lesions ◽

Vertical Posture ◽

Lesion Volume ◽

Precentral Gyrus ◽

Stroke Patients ◽

The Right ◽

Right Hemisphere Stroke

Lateropulsion (pusher syndrome) is an important barrier to standing and gait after stroke. Although several studies have attempted to elucidate the relationship between brain lesions and lateropulsion, the effects of specific brain lesions on the development of lateropulsion remain unclear. Thus, the present study investigated the effects of stroke lesion location and size on lateropulsion in right hemisphere stroke patients. The present retrospective cross-sectional observational study assessed 50 right hemisphere stroke patients. Lateropulsion was diagnosed and evaluated using the Scale for Contraversive Pushing (SCP). Voxel-based lesion symptom mapping (VLSM) analysis with 3T-MRI was used to identify the culprit lesion for SCP. We also performed VLSM controlling for lesion volume as a nuisance covariate, in a multivariate model that also controlled for other factors contributing to pusher behavior. VLSM, combined with statistical non-parametric mapping (SnPM), identified the specific region with SCP. Lesion size was associated with lateropulsion. The precentral gyrus, postcentral gyrus, inferior frontal gyrus, insula and subgyral parietal lobe of the right hemisphere seemed to be associated with the lateropulsion; however, after adjusting for lesion volume as a nuisance covariate, no lesion areas were associated with the SCP scores. The size of the right hemisphere lesion was the only factor most strongly associated with lateropulsion in patients with stroke. These results may be useful for planning rehabilitation strategies of restoring vertical posture and understanding the pathophysiology of lateropulsion in stroke patients.

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