Imagined Viewer and Object Rotations Dissociated with Event-Related fMRI

Human spatial reasoning may depend in part on two dissociable types of mental image transformations: objectbased transformations, in which an object is imagined to move in space relative to the viewer and the environment, and perspective transformations, in which the viewer imagines the scene from a different vantage point. This study measured local brain activity with event-related fMRI while participants were instructed to either imagine an array of objects rotating (an object-based transformation) or imagine themselves rotating around the array (a perspective transformation). Object-based transformations led to selective increases in right parietal cortex and decreases in left parietal cortex, whereas perspective transformations led to selective increases in left temporal cortex. These results argue against the view that mental image transformations are performed by a unitary neural processing system, and they suggest that different overlapping systems are engaged for different image transformations.

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Neural Mechanisms of Visual Attention: Object-Based Selection of a Region in Space

Journal of Cognitive Neuroscience ◽

10.1162/089892900563975 ◽

2000 ◽

Vol 12 (supplement 2) ◽

pp. 106-117 ◽

Cited By ~ 182

Author(s):

Catherine M. Arrington ◽

Thomas H. Carr ◽

Andrew R. Mayer ◽

Stephen M. Rao

Keyword(s):

Visual Attention ◽

Spatial Attention ◽

Brain Activity ◽

Temporal Cortex ◽

Brain Structures ◽

Brain Regions ◽

Brain Areas ◽

Unbounded Region ◽

Object Based ◽

Selection Of

Objects play an important role in guiding spatial attention through a cluttered visual environment. We used event-related functional magnetic resonance imaging (ER-fMRI) to measure brain activity during cued discrimination tasks requiring subjects to orient attention either to a region bounded by an object (object-based spatial attention) or to an unbounded region of space (location-based spatial attention) in anticipation of an upcoming target. Comparison between the two tasks revealed greater activation when attention selected a region bounded by an object. This activation was strongly lateralized to the left hemisphere and formed a widely distributed network including (a) attentional structures in parietal and temporal cortex and thalamus, (b) ventral-stream object processing structures in occipital, inferior-temporal, and parahippocampal cortex, and (c) control structures in medial-and dorsolateral-prefrontal cortex. These results suggest that object-based spatial selection is achieved by imposing additional constraints over and above those processes already operating to achieve selection of an unbounded region. In addition, ER-fMRI methodology allowed a comparison of validly versus invalidly cued trials, thereby delineating brain structures involved in the reorientation of attention after its initial deployment proved incorrect. All areas of activation that differentiated between these two trial types resulted from greater activity during the invalid trials. This outcome suggests that all brain areas involved in attentional orienting and task performance in response to valid cues are also involved on invalid trials. During invalid trials, additional brain regions are recruited when a perceiver recovers from invalid cueing and reorients attention to a target appearing at an uncued location. Activated brain areas specific to attentional reorientation were strongly right-lateralized and included posterior temporal and inferior parietal regions previously implicated in visual attention processes, as well as prefrontal regions that likely subserve control processes, particularly related to inhibition of inappropriate responding.

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Enhancing spatial reasoning by anodal transcranial direct current stimulation over the right posterior parietal cortex

Experimental Brain Research ◽

10.1007/s00221-019-05699-5 ◽

2019 ◽

Vol 238 (1) ◽

pp. 181-192

Author(s):

Julia Wertheim ◽

Lorenza S. Colzato ◽

Michael A. Nitsche ◽

Marco Ragni

Keyword(s):

Parietal Cortex ◽

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Posterior Parietal Cortex ◽

Spatial Reasoning ◽

Direct Current Stimulation ◽

Posterior Parietal ◽

The Right

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Cerebral mycetoma with cranial osteomyelitis

Journal of Neurosurgery Pediatrics ◽

10.3171/ped/2008/1/6/493 ◽

2008 ◽

Vol 1 (6) ◽

pp. 493-495 ◽

Cited By ~ 10

Author(s):

Vamseemohan Beeram ◽

Sundaram Challa ◽

Prasad Vannemreddy

Keyword(s):

Computed Tomography ◽

Cerebral Cortex ◽

Parietal Cortex ◽

Subcutaneous Tissue ◽

Young Male ◽

Ct Scanning ◽

Parietal Bone ◽

Total Excision ◽

Farm Laborer ◽

Left Parietal Cortex

✓ Craniocerebral maduromycetoma is extremely rare. The authors describe a case of maduromycetoma involving the left parietal cortex, bone, and subcutaneous tissue in a young male farm laborer who presented with left parietal scalp swelling that had progressed into a relentlessly discharging sinus. Computed tomography (CT) scanning of his brain revealed osteomyelitis of the parietal bone with an underlying homogeneously enhancing tumor. Intraoperatively, the mass was revealed to be a black lesion involving the bone, dura mater, and underlying cerebral cortex. It was friable and separated from the surrounding brain by a thick gliotic scar. Gross-total excision was performed, and the patient was placed on a 6-week regimen of itraconazole. To the authors' knowledge, this is the first instance of cerebral mycetoma with CT findings reported in the literature.

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Brain Activation During Reading in Deep Dyslexia: An MEG Study

Journal of Cognitive Neuroscience ◽

10.1162/089892900562381 ◽

2000 ◽

Vol 12 (4) ◽

pp. 622-634 ◽

Cited By ~ 14

Author(s):

Matti Laine ◽

Riitta Salmelin ◽

Päivi Helenius ◽

Reijo Marttila

Keyword(s):

Semantic Processing ◽

Semantic Analysis ◽

Right Hemisphere ◽

Word Reading ◽

Brain Activity ◽

Temporal Cortex ◽

Single Word ◽

Lexical Semantic ◽

Deep Dyslexia ◽

Single Word Reading

Magnetoencephalographic (MEG) changes in cortical activity were studied in a chronic Finnish-speaking deep dyslexic patient during single-word and sentence reading. It has been hypothesized that in deep dyslexia, written word recognition and its lexical-semantic analysis are subserved by the intact right hemisphere. However, in our patient, as well as in most nonimpaired readers, lexical-semantic processing as measured by sentence-final semantic-incongruency detection was related to the left superior-temporal cortex activation. Activations around this same cortical area could be identified in single-word reading as well. Another factor relevant to deep dyslexic reading, the morphological complexity of the presented words, was also studied. The effect of morphology was observed only during the preparation for oral output. By performing repeated recordings 1 year apart, we were able to document significant variability in both the spontaneous activity and the evoked responses in the lesioned left hemisphere even though at the behavioural level, the patient's performance was stable. The observed variability emphasizes the importance of estimating consistency of brain activity both within and between measurements in brain-damaged individuals.

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Cortical control of Inhibition of Return: Exploring the causal contributions of the left parietal cortex

Cortex ◽

10.1016/j.cortex.2013.08.004 ◽

2013 ◽

Vol 49 (10) ◽

pp. 2927-2934 ◽

Cited By ~ 22

Author(s):

Alexia Bourgeois ◽

Ana B. Chica ◽

Antoni Valero-Cabré ◽

Paolo Bartolomeo

Keyword(s):

Parietal Cortex ◽

Inhibition Of Return ◽

Cortical Control ◽

Left Parietal Cortex

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Increased connectivity among sensory and motor regions during visual and audiovisual speech perception

10.1101/2020.12.15.422726 ◽

2020 ◽

Author(s):

Jonathan E Peelle ◽

Brent Spehar ◽

Michael S Jones ◽

Sarah McConkey ◽

Joel Myerson ◽

...

Keyword(s):

Visual Cortex ◽

Speech Perception ◽

Brain Activity ◽

Premotor Cortex ◽

Temporal Cortex ◽

Primary Auditory Cortex ◽

Visual Speech ◽

Auditory Signal ◽

Audiovisual Speech ◽

Audiovisual Speech Perception

In everyday conversation, we usually process the talker's face as well as the sound of their voice. Access to visual speech information is particularly useful when the auditory signal is degraded. Here we used fMRI to monitor brain activity while adults (n = 60) were presented with visual-only, auditory-only, and audiovisual words. As expected, audiovisual speech perception recruited both auditory and visual cortex, with a trend towards increased recruitment of premotor cortex in more difficult conditions (for example, in substantial background noise). We then investigated neural connectivity using psychophysiological interaction (PPI) analysis with seed regions in both primary auditory cortex and primary visual cortex. Connectivity between auditory and visual cortices was stronger in audiovisual conditions than in unimodal conditions, including a wide network of regions in posterior temporal cortex and prefrontal cortex. Taken together, our results suggest a prominent role for cross-region synchronization in understanding both visual-only and audiovisual speech.

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Decoding Human Emotional Faces in the Dog’s Brain

10.1101/134080 ◽

2017 ◽

Cited By ~ 1

Author(s):

Raúl Hernández-Pérez ◽

Luis Concha ◽

Laura V. Cuaya

Keyword(s):

Support Vector Machine Classifier ◽

Brain Activity ◽

Temporal Cortex ◽

Support Vector ◽

Functional Magnetic Resonance ◽

Resonance Imaging ◽

Emotional Faces ◽

Time Courses ◽

Human Faces ◽

Brain Fmri

AbstractDogs can interpret emotional human faces (especially the ones expressing happiness), yet the cerebral correlates of this process are unknown. Using functional magnetic resonance imaging (fMRI) we studied eight awake and unrestrained dogs. In Experiment 1 dogs observed happy and neutral human faces, and found increased brain activity when viewing happy human faces in temporal cortex and caudate. In Experiment 2 the dogs were presented with human faces expressing happiness, anger, fear, or sadness. Using the resulting cluster from Experiment 1 we trained a linear support vector machine classifier to discriminate between pairs of emotions and found that it could only discriminate between happiness and the other emotions. Finally, evaluation of the whole-brain fMRI time courses through a similar classifier allowed us to predict the emotion being observed by the dogs. Our results show that human emotions are specifically represented in dogs’ brains, highlighting their importance for inter-species communication.

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Altered effective connectivity in migraine patients during emotional stimuli: a multi-frequency magnetoencephalography study

The Journal of Headache and Pain ◽

10.1186/s10194-021-01379-4 ◽

2022 ◽

Vol 23 (1) ◽

Author(s):

Jing Ren ◽

Qun Yao ◽

Minjie Tian ◽

Feng Li ◽

Yueqiu Chen ◽

...

Keyword(s):

Brain Activity ◽

Effective Connectivity ◽

Temporal Cortex ◽

Primary Headache ◽

Clustering Coefficient ◽

Frequency Range ◽

Emotional Stimuli ◽

Emotional Modulation ◽

Gamma Frequency ◽

Wide Range

Abstract Background Migraine is a common and disabling primary headache, which is associated with a wide range of psychiatric comorbidities. However, the mechanisms of emotion processing in migraine are not fully understood yet. The present study aimed to investigate the neural network during neutral, positive, and negative emotional stimuli in the migraine patients. Methods A total of 24 migraine patients and 24 age- and sex-matching healthy controls were enrolled in this study. Neuromagnetic brain activity was recorded using a whole-head magnetoencephalography (MEG) system upon exposure to human facial expression stimuli. MEG data were analyzed in multi-frequency ranges from 1 to 100 Hz. Results The migraine patients exhibited a significant enhancement in the effective connectivity from the prefrontal lobe to the temporal cortex during the negative emotional stimuli in the gamma frequency (30–90 Hz). Graph theory analysis revealed that the migraine patients had an increased degree and clustering coefficient of connectivity in the delta frequency range (1–4 Hz) upon exposure to positive emotional stimuli and an increased degree of connectivity in the delta frequency range (1–4 Hz) upon exposure to negative emotional stimuli. Clinical correlation analysis showed that the history, attack frequency, duration, and neuropsychological scales of the migraine patients had a negative correlation with the network parameters in certain frequency ranges. Conclusions The results suggested that the individuals with migraine showed deviant effective connectivity in viewing the human facial expressions in multi-frequencies. The prefrontal-temporal pathway might be related to the altered negative emotional modulation in migraine. These findings suggested that migraine might be characterized by more universal altered cerebral processing of negative stimuli. Since the significant result in this study was frequency-specific, more independent replicative studies are needed to confirm these results, and to elucidate the neurocircuitry underlying the association between migraine and emotional conditions.

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Causal relations between cortical network oscillations and breathing frequency

10.1101/2020.12.05.412999 ◽

2020 ◽

Author(s):

Adriano BL Tort ◽

Maximilian Hammer ◽

Jiaojiao Zhang ◽

Jurij Brankačk ◽

Andreas Draguhn

Keyword(s):

Parietal Cortex ◽

Instantaneous Frequency ◽

Time Scale ◽

Brain Activity ◽

Gamma Oscillations ◽

Cortical Network ◽

Breathing Rate ◽

Breathing Frequency ◽

Nasal Breathing ◽

Network Oscillations

AbstractNasal breathing generates a rhythmic signal which entrains cortical network oscillations in widespread brain regions on a cycle-to-cycle time scale. It is unknown, however, how respiration and neuronal network activity interact on a larger time scale: are breathing frequency and typical neuronal oscillation patterns correlated? Is there any directionality or causal relationship? To address these questions, we recorded field potentials from the posterior parietal cortex of mice together with respiration during REM sleep. In this state, the parietal cortex exhibits prominent theta and gamma oscillations while behavioral activity is minimal, reducing confounding signals. We found that the instantaneous breathing rate strongly correlates with the instantaneous frequency and amplitude of both theta and gamma oscillations. Granger causality analysis revealed specific directionalities for different rhythms: changes in theta activity precede and cause changes in breathing rate, suggesting control of breathing frequency by the functional state of the brain. On the other hand, the instantaneous breathing rate Granger-causes changes in gamma oscillations, suggesting that gamma is influenced by a peripheral reafference signal. These findings show that breathing causally relates to different patterns of rhythmic brain activity, revealing new and complex interactions between elementary physiological functions and neuronal information processing.Significance StatementThe study of the interactions between respiration and brain activity has been focused on phase-entrainment relations, in which cortical networks oscillate phase-locked to breathing cycles. Here we discovered new and much broader interactions which link respiration rate (frequency) to different patterns of oscillatory brain activity. Specifically, we show that the instantaneous breathing rate strongly correlates with the instantaneous frequency and amplitude of theta and gamma oscillations, two major network patterns associated with cognitive functions. Interestingly, causality analyses reveal that changes in breathing rate follow theta, suggesting a central drive, while in contrast, gamma activity follows changes in breathing rate, suggesting the role of a reafferent signal. Our results reveal new mechanisms by which nasal breathing patterns may influence brain functions.

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