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1.
PLoS One ; 19(4): e0298349, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635579

RESUMO

The claustrum is an irregular and fine sheet of grey matter in the basolateral telencephalon present in almost all mammals. The claustrum has been the object of several studies using animal models and, more recently, in human beings using neuroimaging. One of the most extended cognitive processes attributed to the claustrum is the salience process, which is also related to the insular cortex. In the same way, studies with human subjects and functional magnetic resonance imaging have reported the coactivation of the claustrum/insular cortex in the integration of sensory signals. This coactivation has been reported in the left claustrum/insular cortex or in the right claustrum/insular cortex. The asymmetry has been reported in task studies and literature related to neurological disorders such as Alzheimer's disease and schizophrenia, relating the severity of delusions with the reduction in left claustral volume. We present a functional connectivity study of the claustrum. Resting-state functional and anatomical MRI data from 100 healthy subjects were analyzed; taken from the Human Connectome Project (HCP, NIH Blueprint: The Human Connectome Project), with 2x2x2 mm3 voxel resolution. We hypothesize that 1) the claustrum is a node involved in different brain networks, 2) the functional connectivity pattern of the claustrum is different from the insular cortex's pattern, and 3) the asymmetry is present in the claustrum's functional connectivity. Our findings include at least three brain networks related to the claustrum. We found functional connectivity between the claustrum, frontoparietal network, and the default mode network as a distinctive attribute. The functional connectivity between the right claustrum with the frontoparietal network and the dorsal attention network supports the hypothesis of claustral asymmetry. These findings provide functional evidence, suggesting that the claustrum is coupled with the frontoparietal network serving together to instantiate new task states by flexibly modulating and interacting with other control and processing networks.


Assuntos
Claustrum , Conectoma , Animais , Humanos , Encéfalo , Substância Cinzenta/patologia , Córtex Cerebral/diagnóstico por imagem , Imageamento por Ressonância Magnética , Mamíferos
2.
J Neurosci Res ; 102(1): e25252, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38284847

RESUMO

It has been reported that cannabis consumption affects the anterior cingulate cortex (ACC), a structure with a central role in mediating the empathic response. In this study, we compared psychometric scores of empathy subscales, between a group of regular cannabis users (85, users) and a group of non-consumers (51, controls). We found that users have a greater Emotional Comprehension, a cognitive empathy trait involving the understanding of the "other" emotional state. Resting state functional MRI in a smaller sample (users = 46, controls = 34) allowed to identify greater functional connectivity (FC) of the ACC with the left somatomotor cortex (SMC), in users when compared to controls. These differences were also evident within the empathy core network, where users showed greater within network FC. The greater FC showed by the users is associated with emotional representational areas and empathy-related regions. In addition, the differences in psychometric scores suggest that users have more empathic comprehension. These findings suggest a potential association between cannabis use, a greater comprehension of the other's affective state and the functional brain organization of the users. However, further research is needed to explore such association, since many other factors may be at play.


Assuntos
Cannabis , Empatia , Giro do Cíngulo/diagnóstico por imagem , Emoções , Encéfalo , Agonistas de Receptores de Canabinoides
3.
World J Biol Psychiatry ; 25(2): 95-105, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37786280

RESUMO

OBJECTIVE: During hypnosis, significant changes in the BOLD signal associated with the anterior default mode network (DMN) and prefrontal attentional systems have been reported as evidence of dissociation defined since Charcot. However, it remains uncertain whether these changes are mainly attributable to the hypnotic state per se or to the target suggestions used to verify subject's state during neuroimaging studies. The aim of the present study is to evidence the brain in hypnosis, contrasting the common resting state versus neutral hypnosis (hypnosis in the absence of target suggestions). METHODS: Twenty-four healthy right-handed volunteers (age 28.3 y.o., 12 females) rated moderate hypnotic responsiveness underwent resting state fMRI at 3.0 T in two sessions, once in neutral hypnosis and the other in the common resting state. Each subject's functional data were analyzed for low-frequency BOLD signal correlations seed-to-voxel for the whole brain in the first-level analysis, and seed-to-voxel in a second-level analysis to estimate group results using seeds for five resting state networks: the default mode (DMN), the central executive (CEN), the salience (SaN), the dorso-lateral attention (DAN), and the sensorimotor (SMN) networks. RESULTS: In general, all network maps of the hypnotic condition presented higher connectivity than those of the resting condition. However, only contrasts for the DAN, SaN, and SMN were statistically significant, including correlated out-of-the-network regions. CONCLUSION: Parietal and occipital regions displayed increased connectivity across networks, implying dissociation from the frontal cortices. This is the first fMRI intrinsic study of hypnosis without target suggestion.


Assuntos
Hipnose , Imageamento por Ressonância Magnética , Feminino , Humanos , Adulto , Imageamento por Ressonância Magnética/métodos , Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Hipnóticos e Sedativos
4.
eNeuro ; 10(2)2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36717266

RESUMO

Adolescence is a crucial developmental period in terms of behavior and mental health. Therefore, understanding how the brain develops during this stage is a fundamental challenge for neuroscience. Recent studies have modeled the brain as a network or connectome, mainly applying measures from graph theory, showing a change in its functional organization, such as an increase in its segregation and integration. Topological Data Analysis (TDA) complements such modeling by extracting high-dimensional features across the whole range of connectivity values instead of exploring a fixed set of connections. This study inquires into the developmental trajectories of such properties using a longitudinal sample of typically developing human participants (N = 98; 53/45 female/male; 6.7-18.1 years), applying TDA to their functional connectomes. In addition, we explore the effect of puberty on individual developmental trajectories. Results showed that the adolescent brain has a more distributed topology structure compared with random networks but is more densely connected at the local level. Furthermore, developmental effects showed nonlinear trajectories for the topology of the whole brain and fronto-parietal networks, with an inflection point and increasing trajectories after puberty onset. These results add to the insights into the development of the functional organization of the adolescent brain.


Assuntos
Conectoma , Humanos , Masculino , Adolescente , Feminino , Conectoma/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Puberdade , Rede Nervosa
5.
Front Integr Neurosci ; 17: 1027382, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38192686

RESUMO

In a segregated society, marked by a historical background of inequalities, there is a consistent under-representation of ethnic and racial minorities in biomedical research, causing disparities in understanding genetic and acquired diseases as well as in the effectiveness of clinical treatments affecting different groups. The repeated inclusion of small and non-representative samples of the population in neuroimaging research has led to generalization bias in the morphological characterization of the human brain. A few brain morphometric studies between Whites and African Americans have reported differences in orbitofrontal volumetry and insula cortical thickness. Nevertheless, these studies are mostly conducted in small samples and populations with cognitive impairment. For this reason, this study aimed to identify brain morphological variability due to racial identity in representative samples. We hypothesized that, in neurotypical young adults, there are differences in brain morphometry between participants with distinct racial identities. We analyzed the Human Connectome Project (HCP) database to test this hypothesis. Brain volumetry, cortical thickness, and cortical surface area measures of participants identified as Whites (n = 338) or African Americans (n = 56) were analyzed. Non-parametrical permutation analysis of covariance between these racial identity groups adjusting for age, sex, education, and economic income was implemented. Results indicated volumetric differences in choroid plexus, supratentorial, white matter, and subcortical brain structures. Moreover, differences in cortical thickness and surface area in frontal, parietal, temporal, and occipital brain regions were identified between groups. In this regard, the inclusion of sub-representative minorities in neuroimaging research, such as African American persons, is fundamental for the comprehension of human brain morphometric diversity and to design personalized clinical brain treatments for this population.

6.
Front Psychol ; 13: 992935, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36176793

RESUMO

Different theoretical models have proposed cognitive and affective components in empathy and moral judgments encompassing compassion. Furthermore, gender differences in psychological and neural functions involving empathic and moral processing, as well as compassionate experiences, have been reported. However, the neurobiological function regarding affective and cognitive integration underlying compassion and gender-associated differences has not been investigated. In this study, we aimed to examine the interaction between cognitive and emotional components through functional connectivity analyzes and to explore gender differences for the recruitment and interaction of these components. Thirty-six healthy participants (21-56 years; 21 women) were exposed to social images in an fMRI session to judge whether the stimuli elicited compassion. The results showed a different connectivity pattern for women and men of the insular cortex, the dorsomedial prefrontal cortex (dmPFC), the orbitofrontal cortex (OFC), and the cingulate cortex. The integration of affective and cognitive components follows a complex functional connectivity pattern that is different for both genders. These differences may indicate that men largely make compassionate judgments based on contextual information, while women tend to notably take internal and introspective processes into account. Women and men can use different affective and cognitive routes that could converge in similar learning of moral values, empathic experiences and compassionate acts.

7.
Brain Topogr ; 35(5-6): 613-626, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35988094

RESUMO

Empathic abilities have been shown to be linked with brain structural variations. Since psychotherapists constitute a population that tends to display greater empathic abilities, as shown in psychometric differences in cognitive empathy and emotional regulation, we aimed to identify cortical thickness (CT) differences between a group of professional psychotherapists and a control group. In line with the recently emphasized urge to employ more than a single workflow in cortical analyses, we utilized two cortical surface extraction and thickness estimation pipelines-CIVET and FreeSurfer. Eighteen psychotherapists and eighteen controls underwent MRI scanning and completed empathy-related psychometric assessments. We evaluated how CT measures differed between groups and if there was an association with individual empathy-related scores in a series of regions of interest (ROIs). Our analysis with CIVET shows that psychotherapists display a significantly greater CT at a ROI in the left dorsolateral prefrontal cortex (dlPFC; p < 0.05, FDR corrected). With FreeSurfer, a whole-brain vertex-wise analysis identified a statistically significant cluster in the left PFC that partially overlaps with the previous ROI. These results were reinforced by a structural covariance analysis revealing that, in psychotherapists, the left dlPFC ROI seemed to vary independently from the rest of the cortex. These findings are relevant because the dlPFC region importantly participates in the cognitive components of the empathic response, such as emotion regulation and perspective taking. Thus, our findings support the idea that empathic capacity is reflected by brain structural variations while also studying for the first time a sample of subjects for whom empathic responding is crucial in their profession.


Assuntos
Regulação Emocional , Empatia , Humanos , Animais , Psicoterapeutas , Córtex Pré-Frontal Dorsolateral , Viverridae , Imageamento por Ressonância Magnética , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia
8.
eNeurologicalSci ; 27: 100407, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35669231

RESUMO

During a social evaluation, the right temporo-parietal junction (rTPJ) plays an important role according to its contribution in making inferences about the mental states of others. However, what is the neural response if rTPJ function is inhibited during a mentalizing task? In this study, participants played the Dictator Game with two confederates: one playing cooperation (C) and other playing non-cooperation (NC) role and then they were scanned during a mentalizing test. However, we inhibited rTPJ using transcranial magnetic stimulation (TMS) after they played the game and before they were scanned. In this test, participants read negative (Neg) or positive (Pos) personal situations and then they watched confederate's pictures. Images from the TMS group were compared against controls with no TMS stimulation. After statistical comparison, we found a significantly higher activity in right and left visual association areas (BA 18) during the NCPos > NCNeg condition in the TMS group compared with the No-TMS group. Same visual association areas have been described before when participants are processing visual emotional information or when making a fast social categorization. This could reflect a neural mechanism of socio - emotional categorization that emerges after rTPJ inhibition.

9.
Neuropsychologia ; 173: 108300, 2022 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-35697091

RESUMO

Modulation of reflex responses is crucial to adapt our behavior and cognition, and this is especially difficult when biological relevant stimuli are present such as emotional faces. The aim of this study was to identify the effect of peripherally presented happy and angry facial expressions in reflexive saccades and saccadic inhibition/re-orientation of attention. Behavior through eye-tracking technique and fMRI event-related BOLD signals activations were evaluated in adult males during the performance of an antisaccade task. fMRI signals obtained during task performance were compared to a baseline. Results showed that antisaccades had a lower percentage of correct responses and higher latency onsets than prosaccades. At the activation brain level, differences between both emotions and the baseline were found during stimuli presentation. Prosaccades for happy and angry faces recruited larger clusters with higher Z values mainly in occipito-parietal and temporal regions related to visual basic and integration processing, as well as regions of the oculomotor network. Meanwhile, when compared to the baseline, antisaccades recruited similar areas but a lower number of clusters with lower Z values as expected for peripheral processing of faces. At antisaccades, happy faces recruited parieto-occipital, temporal and cerebellar regions, while the angry faces added activation of orbital and ventrolateral prefrontal cortex related to emotional regulation. These results suggest that emotional facial expressions are being processed outside of the focus of attention. Particularly, angry expressions recruit a wider brain network in order to inhibit automatic behavior and re-orientate voluntary attention efficiently that may be due to its biological relevance.


Assuntos
Imageamento por Ressonância Magnética , Movimentos Sacádicos , Adulto , Atenção/fisiologia , Mapeamento Encefálico , Emoções/fisiologia , Expressão Facial , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino
10.
Neuroscience ; 492: 82-91, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35398508

RESUMO

In a therapeutic environment a proper regulation of the empathic response strengthens the patient-therapist relationship. Thus, it is important that psychotherapists constantly regulate their own perspective and emotions to better understand the other's affective state. We compared the empathic abilities of a group of 52 psychotherapists with a group of 92 non-psychotherapists and found psychometric differences. Psychotherapists showed greater scores in Fantasy and Perspective Taking, both cognitive empathy constructs, and lower scores in the use of expressive suppression, an emotional regulation strategy that hampers the empathic response, suggesting that psychotherapists exert top-down processes that influence their empathic response. In addition, the expected sex differences in empathic concern and expressive suppression were only present in the non-psychotherapist group. To see if such psychometric differences were related to a distinctive functional organization of brain networks, we contrasted the resting state functional connectivity of empathy-related brain regions between a group of 18 experienced psychotherapists and a group of 18 non-psychotherapists. Psychotherapists showed greater functional connectivity between the left anterior insula and the dorsomedial prefrontal cortex, and less connectivity between rostral anterior cingulate cortex and the orbito prefrontal cortex. Both associations correlated with Perspective Taking scores. Considering that the psychometric differences between groups were in the cognitive domain and that the functional connectivity associations involve areas related to cognitive regulation processes, these results suggest a relationship between the functional brain organization of psychotherapists and the cognitive regulation of their empathic response.


Assuntos
Empatia , Psicoterapeutas , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
11.
Neuron ; 109(11): 1769-1775, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-33932337

RESUMO

Brainhack is an innovative meeting format that promotes scientific collaboration and education in an open, inclusive environment. This NeuroView describes the myriad benefits for participants and the research community and how Brainhacks complement conventional formats to augment scientific progress.


Assuntos
Comunicação , Internet , Neurociências/organização & administração , Congressos como Assunto , Guias de Prática Clínica como Assunto
12.
Brain Topogr ; 34(4): 430-441, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34008053

RESUMO

The cortical thickness has been used as a biomarker to assess different cerebral conditions and to detect alterations in the cortical mantle. In this work, we compare methods from the FreeSurfer software, the Computational Anatomy Toolbox (CAT12), a Laplacian approach and a new method here proposed, based on the Euclidean Distance Transform (EDT), and its corresponding computational phantom designed to validate the calculation algorithm. At region of interest (ROI) level, within- and inter-method comparisons were carried out with a test-retest analysis, in a subset comprising 21 healthy subjects taken from the Multi-Modal MRI Reproducibility Resource (MMRR) dataset. From the Minimal Interval Resonance Imaging in Alzheimer's Disease (MIRIAD) data, classification methods were compared in their performance to detect cortical thickness differences between 23 healthy controls (HC) and 45 subjects with Alzheimer's disease (AD). The validation of the proposed EDT-based method showed a more accurate and precise distance measurement as voxel resolution increased. For the within-method comparisons, mean test-retest measures (percentages differences/intraclass correlation/Pearson correlation) were similar for FreeSurfer (1.80%/0.90/0.95), CAT12 (1.91%/0.83/0.91), Laplacian (1.27%/0.89/0.95) and EDT (2.20%/0.88/0.94). Inter-method correlations showed moderate to strong values (R > 0.77) and, in the AD comparison study, all methods were able to detect cortical alterations between groups. Surface- and voxel-based methods have advantages and drawbacks regarding computational demands and measurement precision, while thickness definition was mainly associated to the cortical thickness absolute differences among methods. However, for each method, measurements were reliable, followed similar trends along the cortex and allowed detection of cortical atrophies between HC and patients with AD.


Assuntos
Doença de Alzheimer , Processamento de Imagem Assistida por Computador , Doença de Alzheimer/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Reprodutibilidade dos Testes
13.
eNeuro ; 8(3)2021.
Artigo em Inglês | MEDLINE | ID: mdl-33975858

RESUMO

Focused attention to spontaneous sensations is a dynamic process that demands interoceptive abilities. Failure to control it has been linked to neuropsychiatric disorders like illness-anxiety disorder. Regulatory strategies, such as focused attention meditation (FAM), may enhance the ability to control focused attention particularly to body sensations, which can be reflected on functional neuroanatomy. The functional connectivity (FC) related to focused attention has been described, however, the dynamic brain organization associated to this process and the differences to the resting state remains to be studied. To quantify the cerebral dynamic counterpart of focused attention to interoception, we examined fifteen experienced meditators while performing a 20-min attentional task to spontaneous sensations. Subjects underwent three scanning sessions obtaining a resting-state scan before and after the task. Sliding window dynamic FC (DFC) and k-means clustering identified five recurrent FC patterns along the dorsal attention network (DAN), default mode network (DMN), and frontoparietal network (FPN). Subjects remained longer in a low connectivity brain pattern during the resting conditions. By contrast, subjects spent a higher proportion of time in complex patterns during the task than rest. Moreover, a carry-over effect in FC was observed following the interoceptive task performance, suggestive of an active role in the learning process linked to cognitive training. Our results suggest that focused attention to interoceptive processes, demands a dynamic brain organization with specific features that distinguishes it from the resting condition. This approach may provide new insights characterizing the neural basis of the focused attention, an essential component for human adaptability.


Assuntos
Interocepção , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Humanos , Vias Neurais/diagnóstico por imagem , Descanso
14.
Neuroimage ; 229: 117769, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33482398

RESUMO

Adolescence is a developmental period that dramatically impacts body and behavior, with pubertal hormones playing an important role not only in the morphological changes in the body but also in brain structure and function. Understanding brain development during adolescence has become a priority in neuroscience because it coincides with the onset of many psychiatric and behavioral disorders. However, little is known about how puberty influences the brain functional connectome. In this study, taking a longitudinal human sample of typically developing children and adolescents (of both sexes), we demonstrate that the development of the brain functional connectome better fits pubertal status than chronological age. In particular, centrality, segregation, efficiency, and integration of the brain functional connectome increase after the onset of the pubertal markers. We found that these effects are stronger in attention and task control networks. Lastly, after controlling for this effect, we showed that functional connectivity between these networks is related to better performance in cognitive flexibility. This study points out the importance of considering longitudinal nonlinear trends when exploring developmental trajectories, and emphasizes the impact of puberty on the functional organization of the brain in adolescence.


Assuntos
Encéfalo/diagnóstico por imagem , Conectoma/tendências , Rede Nervosa/diagnóstico por imagem , Dinâmica não Linear , Puberdade/fisiologia , Adolescente , Encéfalo/crescimento & desenvolvimento , Criança , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Masculino , Rede Nervosa/crescimento & desenvolvimento , Adulto Jovem
15.
Front Psychol ; 12: 782754, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35153905

RESUMO

This paper shows the brain correlates of Cloninger's personality model during the presentation of social scenarios under positive or negative valence situations. Social scenarios were constructed when participants played the Dictator game with two confederates that had two opposites roles as the cooperator (Coop) and non-cooperator (NoCoop). Later the same day during a fMRI scanning session, participants read negative (Neg) and positive (Pos) situations that happened to confederates in the past. Participants were asked to think "how do you think those people felt during that situation?" A dissimilarity matrix between stimuli were obtained from fMRI results. Results shown that Harm Avoidance trait people make use of right middle frontal gyrus and left superior frontal gyrus to discriminate between Coop and NoCoop. Cooperation as a trait makes use of the right superior temporal gyrus and the right precuneus to discriminate between Coop and NoCoop in positive social scenarios. Finally, Self-directedness trait people make use of the right inferior parietal lobe to discriminate between Coop and NoCoop in negative social scenarios and the right precuneus to discriminate between Coop and Strangers. An intuitive link between discrimination findings and behavioral patterns of those personality traits is proposed.

16.
Front Hum Neurosci ; 14: 203, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32581748

RESUMO

Semantic verbal fluency is among the most employed tasks in cognitive aging research and substantial work is devoted to understanding the underlying mechanisms behind age-related differences at the neural and behavioral levels. The present investigation aimed to evaluate the role of moderating variables, such as age, sex, MMSE, and proxies of cognitive reserve (CR) on the hemodynamic response evoked by semantic verbal fluency in healthy young and healthy older adults. So far, no study has been conducted to this end. To elucidate the exclusive effect of the mentioned variables on brain activation during semantic fluency, finger tapping was included as a control task. Results showed that disregarding adjustments for age, older adults displayed important parietal activations during semantic fluency as well as during finger-tapping. Specifically, the anterior intra-parietal sulcus (IPS) and left inferior parietal lobule (IPL) were areas activated in both tasks in the older group. Younger adults, only displayed parietal activations related to age and sex when these demographics were employed as predictors. Concerning proxies of CR in semantic fluency, the only vocabulary was an important moderator in both age groups. Higher vocabulary scores were associated with lesser activation in occipital areas. Education did not show significant correlations with brain activity during semantic fluency in any of the groups. However, both CR proxies were significantly correlated to brain activations of older adults during finger tapping. Specifically, vocabulary was associated with frontal regions, while education correlated with parietal lobe and cingulate gyrus. Finally, the effects of MMSE were mostly observed on brain activation of older adults in both tasks. These findings demonstrate that the effects of moderating variables on shaping brain activation are intricate and not exclusive of complex verbal tasks. Thus, before adjusting for "nuisance variables," their importance needs to be established. This is especially true for samples including older adults for whom a motor task may be a demanding operation due to normal age-related processes of dedifferentiation.

17.
Neuroimage ; 207: 116343, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31734431

RESUMO

A voxel-based method for measuring sulcal width was developed, validated and applied to a database. This method (EDT-based LM) employs the 3D Euclidean Distance Transform (EDT) of the pial surface and a Local Maxima labeling algorithm. A computational phantom was designed to test method performance; results revealed the method's inaccuracy δ, to range between 0.1 and 0.5 voxels, for a width that varied between 1 and 7 voxels. Two morphological descriptors were computed to characterize each defined sulcus: mean sulcal width (MSW) and mean absolute deviation (MAD). The former is the average width for all available width measurements within the sulcus, and the latter is the deviation of these measurements. The EDT-based LM method was applied to the Minimal Interval Resonance Imaging in the Alzheimer's Disease (MIRIAD) database, for a set of high-resolution Magnetic Resonance (MR) images of 66 subjects: 43 patients with Alzheimer Disease (AD) and 23 control subjects. AD causes significant gray matter loss; hence, some sulci were expected to broaden. Methodological results concurred with this hypothesis. After a Wilcoxon test, MSW was grater in the case of all sulci pertaining to AD patients, (p < 0.05, FDR corrected), whereas MAD showed significant differences in 8 sulci (p < 0.05, FDR corrected). This work presents a novel voxel-based method for measuring sulcal width and extracting descriptors to characterize and compare the sulci within and across subjects.


Assuntos
Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Processamento de Imagem Assistida por Computador , Algoritmos , Mapeamento Encefálico , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino
18.
J Vis Exp ; (152)2019 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-31710027

RESUMO

Conductive hearing loss (CHL) is a prevalent hearing impairment in humans. The goal of the protocol is to describe a simple surgical procedure for inducing CHL in rodents. The protocol demonstrates CHL by tympanic membrane puncture. Verification of CHL surgery was by otoscope examination and behavioral assessment by clap startle response, both replicable and reliable, and are simple methods to demonstrate hearing loss has occurred. The simple CHL procedure is advantageous due to its reproducibility and flexibility to different pursuits in hearing loss research. The limitations of inducing CHL by a surgical approach are associated with the learning curve to perform the surgical procedure and confidence in audiological examination. Inducing a hearing impairment by CHL allows one to readily study the neural manifestations and behavioral outcomes of hearing loss.


Assuntos
Perda Auditiva Condutiva/cirurgia , Otoscópios/normas , Reflexo de Sobressalto/fisiologia , Animais , Feminino , Humanos , Masculino , Ratos , Ratos Sprague-Dawley
19.
Sci Rep ; 9(1): 14787, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31615998

RESUMO

How do humans discriminate emotion from non-emotion? The specific psychophysical cues and neural responses involved with resolving emotional information in sound are unknown. In this study we used a discrimination psychophysical-fMRI sparse sampling paradigm to locate threshold responses to happy and sad acoustic stimuli. The fine structure and envelope of auditory signals were covaried to vary emotional certainty. We report that emotion identification at threshold in music utilizes fine structure cues. The auditory cortex was activated but did not vary with emotional uncertainty. Amygdala activation was modulated by emotion identification and was absent when emotional stimuli were chance identifiable, especially in the left hemisphere. The right hemisphere amygdala was considerably more deactivated in response to uncertain emotion. The threshold of emotion was signified by a right amygdala deactivation and change of left amygdala greater than right amygdala activation. Functional sex differences were noted during binaural uncertain emotional stimuli presentations, where the right amygdala showed larger activation in females. Negative control (silent stimuli) experiments investigated sparse sampling of silence to ensure modulation effects were inherent to emotional resolvability. No functional modulation of Heschl's gyrus occurred during silence; however, during rest the amygdala baseline state was asymmetrically lateralized. The evidence indicates changing hemispheric activation and deactivation patterns between the left and right amygdala is a hallmark feature of discriminating emotion from non-emotion in music.


Assuntos
Tonsila do Cerebelo/fisiologia , Córtex Auditivo/fisiologia , Discriminação Psicológica/fisiologia , Emoções/fisiologia , Música/psicologia , Estimulação Acústica/métodos , Adolescente , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Córtex Auditivo/diagnóstico por imagem , Percepção Auditiva/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Psicoacústica , Fatores Sexuais , Incerteza , Adulto Jovem
20.
Front Neurosci ; 13: 902, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31619943

RESUMO

Humans perceive musical sound as a complex phenomenon, which is known to induce an emotional response. The cues used to perceive emotion in music have not been unequivocally elucidated. Here, we sought to identify the attributes of sound that confer an emotion to music and determine if professional musicians have different musical emotion perception than non-musicians. The objective was to determine which sound cues are used to resolve emotional signals. Happy or sad classical music excerpts modified in fine structure or envelope conveying different degrees of emotional certainty were presented. Certainty was determined by identification of the emotional characteristic presented during a forced-choice discrimination task. Participants were categorized as good or poor performers (n = 32, age 21.16 ± 2.59 SD) and in a separate group as musicians in the first or last year of music education at a conservatory (n = 32, age 21.97 ± 2.42). We found that temporal fine structure information is essential for correct emotional identification. Non-musicians used less fine structure information to discriminate emotion in music compared with musicians. The present psychophysical experiments revealed what cues are used to resolve emotional signals and how they differ between non-musicians and musically educated individuals.

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