Activation In Postcentral Gyrus Research Articles

The relationship between cognitive ability and BOLD activation across sleep-wake states.

The sleep spindle, a waxing and waning oscillation in the sigma frequency range, has been shown to correlate with fluid intelligence; i.e. the ability to use logic, learn novel rules/patterns, and solve problems. Using simultaneous EEG and fMRI, we previously identified the neural correlates of this relationship, including activation of the thalamus, bilateral putamen, medial frontal gyrus, middle cingulate cortex, and precuneus. However, research to date has focussed primarily on non-rapid eye movement (NREM) sleep, and spindles per se, thus overlooking the possibility that brain activity that occurs in other sleep-wake states might also be related to cognitive abilities. In our current study, we sought to investigate whether brain activity across sleep/wake states is also related to human intelligence in N = 29 participants. During NREM sleep, positive correlations were observed between fluid intelligence and blood oxygen level dependent (BOLD) activations in the bilateral putamen and the paracentral lobule/precuneus, as well as between short-term memory (STM) abilities and activity in the medial frontal cortex and inferior frontal gyrus. During wake, activity in bilateral postcentral gyri and occipital lobe was positively correlated with short-term memory abilities. In participants who experienced REM sleep in the scanner, fluid intelligence was positively associated with midbrain activation, and verbal intelligence was associated with right postcentral gyrus activation. These findings provide evidence that the relationship between sleep and intellectual abilities exists beyond sleep spindles.

Functional Magnetic Resonance Imaging of Language Following Constraint-Induced Aphasia Therapy Primed with Intermittent Theta Burst Stimulation in 13 Patients with Post-Stroke Aphasia.

BackgroundAphasia is a debilitating consequence of stroke. This study aimed to investigate the role of functional magnetic resonance imaging (fMRI) activation changes during overt language tasks in promoting language improvements following constraint-induced aphasia therapy (CIAT) primed with intermittent theta burst stimulation (iTBS) in 13 patients with aphasia following ischemic stroke.Material/MethodsParticipants with post-stroke aphasia participated in CIAT primed with iTBS on 10 consecutive weekdays. They also underwent language testing and fMRI while performing overt language tasks at baseline (N=13), immediately post-treatment (N=13), and after 3 months (N=12). Outcome measures were compared between time points, and relationships between changes in language ability and fMRI activation were examined.ResultsWe observed improvements in naming (p<0.001), aphasia symptoms (p=0.038), apraxia of speech symptoms (p=0.040), perception of everyday communicative ability (p=0.001), and the number of spoken words produced during fMRI (p=0.028). Pre- to post-treatment change in naming was negatively correlated with change in right postcentral gyrus activation related to noun-verb associations (rho=−0.554, p=0.0497). Change in aphasia symptoms from immediately after to 3 months post-treatment was negatively correlated with change in bilateral supplementary motor area activation related to verbal encoding (rho=−0.790, p=0.0022).ConclusionsAphasia improvements coupled with fMRI activation changes over time provide support for treatment-induced neuroplasticity with CIAT primed with iTBS. However, a larger randomized sham-controlled study is warranted to confirm our findings and further our understanding of how iTBS can potentiate beneficial effects of language therapy in post-stroke aphasia.

Individual differences in pain sensitivity in drug-naive patients with major depressive disorder: an fMRI study.

Patients with major depressive disorder (MDD) often report pain; however, the pain-related brain mechanism that contributes to MDD with pain remains largely unclear. In the current study, we aimed to observe the cortical responses by employing fMRI technique combined with thermal stimulation paradigm in 17 major depressive disorder patients with pain (MDDP), 19 major depressive disorder patients without pain (MDDNP), and 25 age- and gender-matched healthy control (HC) subjects. Participants completed the Hamilton Depression Rating Scale-17 (HAMD-17) and provided pain intensity ratings in response to noxious heat (51°C) during task-fMRI scanning by visual analogue scale (VAS). In our results, there was no difference in pain intensity ratings during tonic heat stimulation between the HC group and MDDNP group (p > 0.05), while the MDDNP group had significantly higher HAMD scores compared with the HC group (p <0.001). The MDDNP group had decreased brain activation in the postcentral gyrus (PCG) compared with the HC group, implying abnormal activation of the PCG may associate with the characterized depressive mood of painless MDD (p < 0.05). Additionally, there was no difference in HAMD scores between the MDDP group and MDDNP group (p > 0.05), while the MDDP group had significantly greater pain during tonic heat stimulation compared with the MDDNP group (p <0.01). The MDDP group showed enhanced activation in the PCG compared with theMDDNP group (p < 0.05), which may relate to the abnormal regulation of pain in painful MDD. Our results suggested that higher PCG activation may play an important role in facilitating the occurrence of pain in depression.

Characteristics Of Resting State Networks Of Elite Skating Athletes: An ICA Analysis

Long-term motor skill learning can lead neuro plasticity changes. Until now, this conclusion is mainly proved by task fMRI and spontaneous brain activity evidence. However, these methods heavily rely on prior knowledge and hypotheses, and exist algorithm limitations. PURPOSE: To investigate the differences of resting state networks (RSNs) between elite skating athletes and non-athlete controls by means of data-driven approach. METHODS: Resting state fMRI data were acquired by Philips Achieva 3.0T scanner with a standard 32 channel head coil from 15 Chinese national level skating athletes (all men, 20.87±1.78 years old, with an average training year of 9.67±3.50) and 15 demographically matched healthy controls (all men, 20.85±1.83 years old). Gift was used to perform ICA (independent component analysis) arithmetic calculations and identify RSNs, including default mode network, somatomotor network, dorsal attention network, left fronto-parietal network and visual network. A two-sample t-test was then conducted using SPM12 to investigate whether there were significant differences between two groups. Results were reported when voxel significant at a level of p < 0.01. Cluster-level whole-brain family wise error (FWE) was applied for multiple comparison correction (cluster p< 0.01). Coordinates are given in Montreal Neurological Institute(MNI) space. RESULTS: 1. Athletes showed higher spontaneous activity in postcentral gyrus (cluster size =230, peak coordinate =69, -12,18, peak t =11.88) and cingulate gyrus (cluster size =167, peak coordinate= 6, -3,39, peak t =6.65) in somatomotor network. 2. Athletes showed higher spontaneous activity in precuneus (cluster size =337, peak coordinate =30, -66,39, peak t =10.38) in dorsal attention network. CONCLUSIONS: Elite skating athletes showed better functional connectivity in somatomotor network and dorsal attention network, which may further indicate that long-term specialized motor training may promote functional network activation patterns.

Emotional, especially negative microblogs are more popular on the web: evidence from an fMRI study.

Microblogs are one of the main social networking channels by which information is spread. Millions of users repost information from microblogs and share embedded emotion at the same time. The present study employed a mimicked interface of microblog (sina Weibo) and recruited university students to investigate users' propensity to repost microblogs of positive, negative or neutral valence, and studied the neural correlates with reposting microblogs of different emotional valence. Ninety pieces of microblog messages, consisting of 30 positive, 30 negative and 30 neutral were read by 28 participants (14 males and 14 females). Their propensity to repost, valence-related neural activity, and reposting-related neural activity were recorded when they read messages and decided whether to repost them. We found reposting behavior was moderated by emotion. Participants preferred to reposting emotional microblogs relative to neutral microblogs, corresponding to amplified activity in dorsolateral prefrontal cortex (DLPFC), insula, precuneus and tempoparietal junction (TPJ), the key nodes of cognitive control, emotion, self-relevance processing and mentalizing respectively. Moreover, negative microblogs were more reposted than positive ones, corresponding to amplified activity in postcentral gyrus, superior frontal gyrus (SFG) and TPJ. Reposting negative microblogs induced increased activity in bilateral TPJ, indicating that TPJ plays a key role on decisions to propagate negative information. These findings reveal an important behavioral pattern in which negative information prevails in the transmission through microblogs, as well as the neural correlates with this process. It also provides empirical evidence of how reposting works in microblogs and how the brain is involved in social propagation of information.

P 36 Structural and functional imaging findings in somatoparaphrenia

Background With regard to somatosensory delusion, neglect or deficits of body integrity a great number of overlapping pathophysiological concepts exist. Moreover, the range of assumed underlying psychiatric and neurologic syndromes only partially is thought to be related to even diverse neuroanatomical structures so far: Alien Hand Syndrome, Body Dysmorphic Disorder (BDD), Body Integrity Identity Disorder (BIID), Depersonalization, Somatoparaphrenia and Xenomelia. Specific deafferentiation within temporal regions, the insula or representational structures of the somatosensory cortex of the right parietal lobe is thought to be related only in some variants. We report a case of a 58-year old right-handed woman that experienced a progressive left-sided hemiparesis which initially could be related to a space occupying lesion and edema in the right central region of the brain. After anti-edematous therapy and consecutive surgical evacuation a cortical and subcortical defect in between the right postcentral gyrus junction to the precentral gyrus resulted into inanimate, not inherent sensations especially of the left forearm and knee without anosognosia after complete recovery of motor function and sensitivity. The neuropsychological assessment showed no impairments. Methods We demonstrate structural (conventional MRI) and functional imaging findings (diffusion tensor imaging; DTI, and, motor and somatosensory functional MRI) in relation to the subject”s somatosensory delusions. Results Structural MRI displayed a well-defined cortical and subcortical lesion in deep central sulcus surrounded by gliosis and hemosiderin deposits. DTI revealed a marked reduction of structural inter-connection between precentral and postcentral gyrus. In fMRI the motor paradigm series of dorsal flexion of the feet or clenching the fists showed no difference in activation of the correspondent precentral gyrus. The sensor paradigm series in contrast revealed a lower posterior activation of the right postcentral area during brushing the planta pedis and the left forearm. Discussion The hereby presented case possesses rare clinically segregated symptoms of somatoparaphrenia without anosognosia or hemiparesis in conjunction with a well-defined postcentral lesion. The symptoms may be related to a corresponding reduced postcentral activation and restricted functional interconnection between motor and sensory cortex. From our point of view these results document the essential requirement of postcentral gyrus activation and regional conduction for regular experience of sensorial authenticity.

Obesity and Brain Positron Emission Tomography.

Obesity, an increasingly common problem in modern societies, results from energy intake chronically exceeding energy expenditure. This imbalance of energy can be triggered by the internal state of the caloric equation (homeostasis) and non-homeostatic factors, such as social, cultural, psychological, environmental factors or food itself. Nowadays, positron emission tomography (PET) radiopharmaceuticals have been examined to understand the cerebral control of food intake in humans. Using 15O-H2 PET, changes in regional cerebral blood flow (rCBF) coupled to neuronal activity were reported in states of fasting, satiation after feeding, and sensory stimulation. In addition, rCBF in obese subjects showed a greater increase in insula, the primary gustatory cortex. 18F-fluorodeoxyglucose PET showed higher metabolic activity in postcentral gyrus of the parietal cortex and lower in prefrontal cortex and anterior cingulate cortex in obese subjects. In addition, dopamine receptor (DR) PET demonstrated lower DR availability in obese subjects, which might lead to overeating to compensate. Brain PET has been utilized to reveal the connectivity between obesity and brain. This could improve understanding of obesity and help develop a new treatment for obesity.

Influence Of Physical Activity And Sedentary Behavior On Anticipation-related Pain Sensitivity In Gulf War Veterans With Chronic Muscle Pain

Exercise can alter pain sensitivity among Gulf War Veterans with chronic muscle pain (CMP). Anticipation of a painful experience can influence perceptual and neural responses to non-painful thermal stimuli among Fibromyalgia patients and this may extend to other patient groups with CMP. However, the association between physical activity or sedentary behavior and anticipation-related pain sensitivity has not been adequately studied. PURPOSE: To determine if (i) anticipation of pain influenced perceptual and neural responses to thermal stimuli among Veterans with CMP and (ii) anticipation-related pain sensitivity was associated with physical activity or sedentary behavior. METHODS: Gulf War Veterans with (n=29; 46±6.5 years) and without (n=29; 45±6.7 years) CMP were randomly assigned to conditions in which they were told that they would receive a painful or non-painful heat stimulus. Following one week of physical activity monitoring (ActiGraph GT3X), functional MRI responses to a 20-second warm stimulus (40C) applied to the left palm were measured on a 3T MRI scanner (GE MR750). Participants were then asked to provide ratings of pain intensity and unpleasantness following thermal stimulus administration. RESULTS: Factorial ANOVA with group and condition as between-subjects factors revealed significantly higher pain intensity (p =.003; d =.85) and unpleasantness (p =.006; d=0.76) ratings in the pain anticipation condition. A main effect for group and condition by group interaction was not found. Analyses of fMRI responses showed significantly different lateral postcentral gyrus activation in the pain anticipation condition. Linear regression analyses on Veterans in the pain anticipation condition showed that physical activity (e.g., moderate-vigorous physical activity) and sedentary behavior (e.g., average sedentary bouts of 30 or 60 minutes) did not significantly predict perception of pain intensity or unpleasantness. CONCLUSION: Pain anticipation influences perceptual and neural responses to non-painful stimuli among Gulf War Veterans with or without CMP; however, physical activity or sedentary behavior may not be related to anticipation-related pain sensitivity in this population. Supported by Dept. of Veterans Affairs grant: 561-00436

Prefrontal Reactivity to Social Signals of Threat as a Predictor of Treatment Response in Anxious Youth.

Neuroimaging has shown promise as a tool to predict likelihood of treatment response in adult anxiety disorders, with potential implications for clinical decision-making. Despite the relatively high prevalence and emergence of anxiety disorders in youth, very little work has evaluated neural predictors of response to treatment. The goal of the current study was to examine brain function during emotional face processing as a predictor of response to treatment in children and adolescents (age 7-19 years; N=41) with generalized, social, and/or separation anxiety disorder. Prior to beginning treatment with the selective serotonin reuptake inhibitor (SSRI) sertraline or cognitive behavior therapy (CBT), participants completed an emotional faces matching task during functional magnetic resonance imaging (fMRI). Whole brain responses to threatening (ie, angry and fearful) and happy faces were examined as predictors of change in anxiety severity following treatment. Greater activation in inferior and superior frontal gyri, including dorsolateral prefrontal cortex and ventrolateral prefrontal cortex, as well as precentral/postcentral gyri during processing of threatening faces predicted greater response to CBT and SSRI treatment. For processing of happy faces, activation in postcentral gyrus was a significant predictor of treatment response. Post-hoc analyses indicated that effects were not significantly moderated by type of treatment. Findings suggest that greater activation in prefrontal regions involved in appraising and regulating responses to social signals of threat predict better response to SSRI and CBT treatment in anxious youth and that neuroimaging may be a useful tool for predicting how youth will respond to treatment.

Shared Cortical Systems for Processing of Horizontal and Vertical Sound Motion

Cortical processing of horizontal and vertical sound motion in free-field space was investigated using high-density electroencephalography in combination with standardized low-resolution brain electromagnetic tomography (sLORETA). Eighteen subjects heard sound stimuli that, after an initial stationary phase in a central position, started to move centrifugally, either to the left, to the right, upward, or downward. The delayed onset of both horizontal and vertical motion elicited a specific motion-onset response (MOR), resulting in widely distributed activations, with prominent maxima in primary and nonprimary auditory cortices, insula, and parietal lobe. The comparison of MORs to horizontal and vertical motion orientations did not indicate any significant differences in latency or topography. Contrasting the sLORETA solutions for the two motion orientations revealed only marginal activation in postcentral gyrus. These data are consistent with the notion that azimuth and elevation components of dynamic auditory spatial information are processed in common, rather than separate, cortical substrates. Furthermore, the findings support the assumption that the MOR originates at a stage of auditory analysis after the different spatial cues (interaural and monaural spectral cues) have been integrated into a unified space code.

Bilateral Frontal Activation Associated with Cutaneous Stimulation of Elixir Field: An fMRI Study

Elixir Field, or Dan Tian, is the area where energy is stored and nourished in the body according to traditional Chinese medicine (TCM). Although Dan Tian stimulation is a major concept in Qigong healing and has been practiced for thousands of years, and while there are some recent empirical evidence of its effect, its neurophysiological basis remains unknown. We used functional magnetic resonance imaging (fMRI) to study brain activations associated with external stimulation of the lower Elixir Field in ten normal subjects, and compared the results with the stimulation of their right hands. While right-hand stimulation resulted in left postcentral gyrus activation, stimulation of the lower Elixir Field resulted in bilateral activations including the medial and superior frontal gyrus, middle and superior temporal gyrus, thalamus, insula, and cingulate gyrus. These findings suggest that stimulation of the Elixir Field is not only associated with activation of the sensory motor cortex but also with cortical regions that mediate planning, attention, and memory.

Neural correlates of switching set as measured in fast, event-related functional magnetic resonance imaging.

Attentional switching has shown to involve several prefrontal and parietal brain regions. Most cognitive paradigms used to measure cognitive switching such as the Wisconsin Card Sorting Task (WCST) involve additional cognitive processes besides switching, in particular working memory (WM). It is, therefore, questionable whether prefrontal brain regions activated in these conditions, especially dorsolateral prefrontal cortex (DLPFC), are involved in cognitive switching per se, or are related to WM components involved in switching tasks. Functional magnetic resonance imaging (fMRI) was used to examine neural correlates of pure switching using a paradigm purposely designed to minimize WM functions. The switching paradigm required subjects to switch unpredictably between two spatial dimensions, clearly indicated throughout the task before each trial. Fast, event-related fMRI was used to compare neural activation associated with switch trials to that related to repeat trials in 20 healthy, right-handed, adult males. A large cluster of activation was observed in the right hemisphere, extending from inferior prefrontal and pre- and postcentral gyri to superior temporal and inferior parietal cortices. A smaller and more caudal cluster of homologous activation in the left hemisphere was accompanied by activation of left dorsolateral prefrontal cortex (DLPFC). We conclude that left DLPFC activation is involved directly in cognitive switching, in conjunction with parietal and temporal brain regions. Pre- and postcentral gyrus activation may be related to motor components of switching set.

Measurements of brain magnetic fields associated with apparent self-motion

We investigated the cortical sites that process sensations of apparent self-motion (vection) using magnetoencephalography (MEG). Expanding rectangles were presented on the black screen continuously to make the subjects feel as if they go through a tunnel. Seven healthy volunteers were carefully selected and previously trained to experience vections. For both the vection and the control stimuli, the activation of post-central gyrus, infero-posterior temporal lobe, lingual/fusiform gyrus were found. On the other hand, activations in posterior, posterior operculum, parietal lobule, pre-central gyrus, superior temporal gyrus were observed only for vection stimulus. These areas may be human analogs of vestibular cortex identified by former studies in monkey. The results also suggest that these areas integrate multi-modal information.