Search results for "Insular cortex"
showing 10 items of 25 documents
Neural correlates of disturbed perception of verticality.
2012
Objective: Perception of verticality can be perturbed after cortical stroke. However, a relationship between lesion location and pathologic perception of verticality is still a matter of debate since previous studies revealed contradictory results. Thus, the aim of the current study was to test whether specific cortical lesions were associated with tilts of subjective visual vertical (SVV) and to determine the critical brain areas that cause such tilts in the case of a lesion. Methods: SVV was systematically studied in 54 patients (22 patients with left-sided and 32 patients with right-sided lesions) with acute unilateral strokes, analyzed by modern voxel-wise lesion-behavior mapping techni…
2021
In humans and mammals, effort-based decision-making for monetary or food rewards paradigms contributes to the study of adaptive goal-directed behaviours acquired through reinforcement learning. Chronic distress modelled by repeated exposure to glucocorticoids in rodents induces suboptimal decision-making under uncertainty by impinging on instrumental acquisition and prompting negative valence behaviours. In order to further disentangle the motivational tenets of adaptive decision-making, this study addressed the consequences of enduring distress on relevant effort and reward-processing dimensions. Experimentally, appetitive and consummatory components of motivation were evaluated in adult C…
Chronic Distress in Male Mice Impairs Motivation Compromising Both Effort and Reward Processing With Altered Anterior Insular Cortex and Basolateral …
2021
AbstractIn humans and mammals, effort-based decision-making for monetary or food rewards paradigms contribute to the study of adaptive goal-directed behaviours acquired through reinforcement learning. Chronic distress modelled by repeated exposure to glucocorticoids in rodents induces suboptimal decision-making under uncertainty by impinging on instrumental acquisition and prompting negative valence behaviours. In order to further disentangle the motivational tenets of adaptive decision-making, this study addressed the consequences of enduring distress on relevant effort and reward processing dimensions. Experimentally, appetitive and consummatory components of motivation were evaluated in …
N-Acetylaspartate/Creatine and Choline/Creatine Ratios in the Thalami, Insular Cortex and White Matter as Markers of Hypertension and Cognitive Impai…
2008
International audience; Abstract: Our objective was to investigate the influence of hypertension on N-acetylaspartate (NAA) and choline (Cho) ratios in brain tissues in a community-dwelling elderly population. Brain flexibility was also evaluated with regard to the same metabolite ratios. Proton magnetic resonance spectroscopy (MRS) and the Trail Making Test (TMT) were performed in 80 subjects (75.7 +/- 4 years old) from the Three-City Study. Fifty-eight participants had hypertension. The NAA/creatine (Cr) and Cho/Cr ratios were obtained in the insular cortex, the thalami and the deep periventricular white matter. In addition, the B-A score of the TMT was evaluated. Uniand multi-variate ana…
A basal ganglia-like cortical-amygdalar-hypothalamic network mediates feeding behavior.
2020
International audience; The network connecting the insular cortex, the central nucleus of the amygdala, and a caudal hypothalamic nuclear complex including the parasubthalamic nucleus (PSTN) is of interest due to its role in controlling feeding behavior. Here, we show that the organization of this network is similar to that of the basal ganglia network, implying that both fit within a simplified structural plan of the forebrain. Then, we demonstrate that the PSTN complex modulates behavior in response to hedonic factors normally inducing a “reward effect.” The PSTN complex is involved in a “non-feed” response equivalent of a “non-reward” evaluation: “I don’t want to consume this food, recog…
Effects of electrical stimulation in vestibular cortex areas in humans.
2010
The case of a patient with focal epilepsy is reported who underwent presurgical evaluation by stereotactic intracranial electroencephalographic (EEG) recording. A subdural semi-grid electrode, consisting of three multi-channel strip electrodes, was implanted over the temporal lobe and temporo-occipital region; one multi-channel depth electrode was applied towards the posterior insular cortex. During electrical stimulation and EEG monitoring eye movements were recorded by 3-D video-oculography. Stimulation of the medial temporal gyrus induced blurring of vision and horizontal nystagmus. Stimulation of the superior temporal gyrus with low intensities also induced blurring of vision and a simi…
Clinical presentation of strokes confined to the insula: a systematic review of literature
2021
Abstract Background and purpose The insular cortex serves a wide variety of functions in humans, ranging from sensory and affective processing to high-level cognition. Hence, insular dysfunction may result in several different presentations. Ischemic strokes limited to the insular territory are rare and deserve a better characterization, to be quickly recognized and to receive appropriate treatment (e.g. thrombolysis). Methods We reviewed studies on patients with a first-ever acute stroke restricted to the insula. We searched in the Medline database the keywords “insular stroke” and “insular infarction”, to identify previously published cases. Afterwards, the results were divided depending …
Insular strokes cause no vestibular deficits.
2013
Background and Purpose— In previous imaging studies, the posterior insular cortex (IC) was identified as an essential part for vestibular otolith perception and considered as a core region of a human vestibular cortical network. However, it is still unknown whether lesions exclusively restricted to the posterior IC suffice to provoke signs of vestibular otolith dysfunction. Thus, present data aimed to test whether patients with lesions restricted to the IC showed vestibular otolith dysfunction. Methods— We studied 10 acute unilateral stroke patients with lesions restricted to the IC which were tested for signs of vestibular otolith dysfunction, such as tilts of subjective visual vertical, …
Modeling Vestibular Compensation: Neural Plasticity Upon Thalamic Lesion.
2020
The present study in rats was conducted to identify brain regions affected by the interruption of vestibular transmission and to explore selected aspects of their functional connections. We analyzed, by positron emission tomography (PET), the regional cerebral glucose metabolism (rCGM) of cortical, and subcortical cerebral regions processing vestibular signals after an experimental lesion of the left laterodorsal thalamic nucleus, a relay station for vestibular input en route to the cortical circuitry. PET scans upon galvanic vestibular stimulation (GVS) were conducted in each animal prior to lesion and at post-lesion days (PLD) 1, 3, 7, and 20, and voxel-wise statistical analysis of rCGM a…
Comparison of anterior cingulate vs. insular cortex as targets for real-time fMRI regulation during pain stimulation
2014
© 2014 Emmert Breimhorst Bauermann Birklein Van De Ville and Haller. Real time functional magnetic resonance imaging (rt fMRI) neurofeedback allows learning voluntary control over specific brain areas by means of operant conditioning and has been shown to decrease pain perception. To further increase the effect of rt fMRI neurofeedback on pain we directly compared two different target regions of the pain network notably the anterior insular cortex (AIC) and the anterior cingulate cortex (ACC). Participants for this prospective study were randomly assigned to two age matched groups of 14 participants each (7 females per group) for AIC and ACC feedback. First a functional localizer using bloc…