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1.
Child Psychiatry Hum Dev ; 52(6): 1131-1142, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33145671

RESUMO

Early attentional dysfunction is one of the most consistent findings in autism spectrum disorder (ASD), including the high functioning autism (HFA). There are no studies that assess how the atypical attentional processes affect the motor functioning in HFA. In this study, we evaluated attentional and motor functioning in a sample of 15 drug-naive patients with HFA and 15 healthy children (HC), and possible link between attentional dysfunction and motor impairment in HFA. Compared to HC, HFA group was seriously impaired in a considerable number of attentional processes and showed a greater number of motor abnormalities. Significant correlations between attention deficits and motor abnormalities were observed in HFA group. These preliminary findings suggest that deficit of attentional processes can be implied in motor abnormalities in HFA.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Transtorno Autístico , Criança , Humanos
2.
Neuroimage ; 191: 380-391, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30798009

RESUMO

In Generalized Anxiety Disorder (GAD), fluctuations in ongoing thoughts (i.e., mind-wandering) often take the form of rigid and intrusive perseverative cognition, such as worry. Here, we sought to characterise the neural correlates of mind-wandering and perseverative cognition, alongside autonomic nervous system indices of central arousal, notably pupil dilation. We implemented a protocol incorporating the dynamic delivery of thought-probes within a functional neuroimaging task. Sixteen individuals with GAD and sixteen matched healthy controls (HC) underwent functional magnetic resonance imaging with concomitant pupillometry. Participants performed a series of low-demand tracking tasks, responding to occasional changes in a target stimulus. Such a task is typically accompanied by self-generated, off-task thinking. Thought-probes were triggered based on an individual's response time (RT) when responding to the change in the target. Subjective reports showed that long RT predicted off-task thinking/mind-wandering. Moreover, long RT and mind-wandering were also associated with larger pupil diameter. This effect was exaggerated in GAD patients during perseverative cognition. Within brain, during both pre-target periods and target events, there were distinct neural correlates for mind-wandering (e.g., anterior cingulate and paracingulate activation at target onset) and perseverative cognition (e.g., opposite patterns of activation in posterior cingulate and cerebellum at target onset in HC and GAD). Results suggest that not only attention systems but also sensory-motor cortices are important during off-task states. Interestingly, changes across the 'default mode network' also tracked fluctuations in pupillary size. Autonomic expression in pupillary changes mirrors brain activation patterns that occur during different forms of repetitive thinking.


Assuntos
Transtornos de Ansiedade/fisiopatologia , Encéfalo/fisiopatologia , Tempo de Reação/fisiologia , Adulto , Nível de Alerta/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pupila
3.
Psychosom Med ; 80(9): 845-852, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29595708

RESUMO

OBJECTIVE: High blood pressure (BP) is associated with reduced pain sensitivity, known as BP-related hypoalgesia. The underlying neural mechanisms remain uncertain, yet arterial baroreceptor signaling, occurring at cardiac systole, is implicated. We examined normotensives using functional neuroimaging and pain stimulation during distinct phases of the cardiac cycle to test the hypothesized neural mediation of baroreceptor-induced attenuation of pain. METHODS: Eighteen participants (10 women; 32.7 (6.5) years) underwent BP monitoring for 1 week at home, and individual pain thresholds were determined in the laboratory. Subsequently, participants were administered unpredictable painful and nonpainful electrocutaneous shocks (stimulus type), timed to occur either at systole or at diastole (cardiac phase) in an event-related design. After each trial, participants evaluated their subjective experience. RESULTS: Subjective pain was lower for painful stimuli administered at systole compared with diastole, F(1, 2283) = 4.82, p = 0.03. Individuals with higher baseline BP demonstrated overall lower pain perception, F(1, 2164) = 10.47, p < .0001. Within the brain, painful stimulation activated somatosensory areas, prefrontal cortex, cingulate cortex, posterior insula, amygdala, and the thalamus. Stimuli delivered during systole (concurrent with baroreceptor discharge) activated areas associated with heightened parasympathetic drive. No stimulus type by cardiac phase interaction emerged except for a small cluster located in the right parietal cortex. CONCLUSIONS: We confirm the negative associations between BP and pain, highlighting the antinociceptive impact of baroreceptor discharge. Neural substrates associated with baroreceptor/BP-related hypoalgesia include superior parietal lobule, precentral, and lingual gyrus, regions typically involved in the cognitive aspects of pain experience.


Assuntos
Pressão Sanguínea/fisiologia , Encéfalo/fisiologia , Diástole/fisiologia , Percepção da Dor/fisiologia , Pressorreceptores/fisiologia , Sístole/fisiologia , Adulto , Encéfalo/diagnóstico por imagem , Estimulação Elétrica , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
4.
J Cogn Neurosci ; 28(9): 1392-405, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27167404

RESUMO

Individuals are able to split attention between separate locations, but divided spatial attention incurs the additional requirement of monitoring multiple streams of information. Here, we investigated divided attention using photos of natural scenes, where the rapid categorization of familiar objects and prior knowledge about the likely positions of objects in the real world might affect the interplay between these spatial and nonspatial factors. Sixteen participants underwent fMRI during an object detection task. They were presented with scenes containing either a person or a car, located on the left or right side of the photo. Participants monitored either one or both object categories, in one or both visual hemifields. First, we investigated the interplay between spatial and nonspatial attention by comparing conditions of divided attention between categories and/or locations. We then assessed the contribution of top-down processes versus stimulus-driven signals by separately testing the effects of divided attention in target and nontarget trials. The results revealed activation of a bilateral frontoparietal network when dividing attention between the two object categories versus attending to a single category but no main effect of dividing attention between spatial locations. Within this network, the left dorsal premotor cortex and the left intraparietal sulcus were found to combine task- and stimulus-related signals. These regions showed maximal activation when participants monitored two categories at spatially separate locations and the scene included a nontarget object. We conclude that the dorsal frontoparietal cortex integrates top-down and bottom-up signals in the presence of distractors during divided attention in real-world scenes.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Percepção Visual/fisiologia , Adulto , Análise de Variância , Mapeamento Encefálico , Feminino , Humanos , Julgamento/fisiologia , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Estimulação Luminosa , Tempo de Reação , Percepção Espacial/fisiologia , Adulto Jovem
5.
Hum Brain Mapp ; 34(12): 3193-203, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22807351

RESUMO

Although apathy has been extensively studied in relation to neuropsychiatric disorders, it is still unclear whether, in healthy people, it should be considered as a physiological phenomenon or whether it is a risk factor for progression to clinical disturbances. Here, we investigated subclinical apathy phenomenology and its brain microstructural correlates in healthy individuals. We submitted 72 participants to a comprehensive clinical assessment, a high-resolution structural MRI and a diffusion tensor imaging scan protocol. Data of individual microstructural (mean diffusivity and fractional anisotropy) variations were processed across genders in relation to the Apathy Rating Scale score. In females, subclinical apathy phenomenology was associated with microstructural variation of the bilateral thalami, the anterior thalamic radiation, the forceps major, and the corona radiate. These are white matter areas mostly connecting the thalami to the frontal and occipital cortices, regions that are known to be implicated in the expression of apathy in clinical samples. No significant relationship with brain microstructure was found in males who showed a positive correlation between subclinical apathy and somatic phenomenology of depression. In conclusion, our results show that in healthy individuals subclinical apathy phenomenology is associated with different mechanisms across genders, and raise the issue about whether brain microstructural changes associated with subclinical apathy in healthy females could be a precocious marker useful in the prediction of progression to more severe apathetic conditions.


Assuntos
Apatia/fisiologia , Mapeamento Encefálico , Encéfalo/fisiologia , Adulto , Idoso , Anisotropia , Imagem de Tensor de Difusão , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Fibras Nervosas Mielinizadas , Caracteres Sexuais , Adulto Jovem
6.
Depress Anxiety ; 30(1): 85-91, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23300113

RESUMO

BACKGROUND: Anhedonia has been mainly reported as a symptom of depression and cognitive impairment in Parkinson's disease (PD) patients. Here, we investigated whether hedonic tone depends on depression and clarified its relationship with the cognitive performance of PD patients with different mood disorders. METHODS: In 254 patients, we assessed hedonic tone using the Snaith-Hamilton Pleasure Scale, depression severity using the Beck Depression Inventory, and cognitive performances using the Mental Deterioration Battery. A structural psychiatric interview was used to diagnose major depressive disorder (MDD) and minor depressive disorder (MIND), according to the DSM-IV-TR criteria. RESULTS: PD patients with diagnosis of MDD were more anhedonic than those with MIND and those without depressive disorders. Reduced hedonic tone correlated with depression severity in patients with MDD and no depressive disorders. In multivariate models that consider depression severity and cognitive performances together, anhedonia was related to increased depression severity and episodic memory (auditory-verbal learning) impairment, in patients with MDD and with increased depression severity and attention impairment in patients with no depressive disorders. In patients with MIND, anhedonia did not correlate with depression severity or any cognitive performance score. DISCUSSION: Our findings suggest that anhedonia is related to depression severity and specific cognitive performances in patients with MDD and with no depressive disorder. By contrast, the reduced hedonic tone in patients with MIND is independent from depression severity and cognition. Thus, anhedonia in PD is a heterogeneous and multidimensional phenomenon and require investigation at different levels.


Assuntos
Anedonia , Transtornos Cognitivos/psicologia , Transtorno Depressivo/psicologia , Doença de Parkinson/psicologia , Idoso , Transtorno Depressivo Maior/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Índice de Gravidade de Doença
7.
Mindfulness (N Y) ; 14(5): 1234-1245, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37304659

RESUMO

Objectives: The COVID-19 pandemic resulted in a dramatic increase in Web-based education, lacking face-to-face student-teacher and student-student interaction, and consequently impairing students' sense of belonging to a community, interoceptive awareness, and academic self-efficacy. This study examined how a brief mindfulness-based intervention in an online university course can be effective in enhancing attention resources, developing a stronger sense of academic self-efficacy, and improving the sense of belonging to a community, which represent critical factors affecting students' participation in online and blended courses. Method: Four-hundred and eighty-six participants (Mage 22.88) completed a battery of measures at pre- and post-treatment. One class (experimental group) participated in a brief online mindfulness-based intervention (42%), whereas the other one (control group) did not take part in the intervention (58%). The intervention included breathing meditation at the beginning of class, sharing of experiences, mini-lectures on mindfulness, and daily practice, and lasted for 28 consecutive days. Results: Participants in the experimental group when compared to controls showed a significant increase in the feeling of influencing the course activities (F = 9.628; p < 0.005), in the self-regulation of attention (F = 19.133; p < 0.001), in academic self-efficacy (F = 9.220; p < 0.005), and, particularly, in their self-efficacy in regulating learning (F = 12.942; p < 0.001). The students' adherence to the assigned practice could partially explain the effectiveness of the intervention. Conclusions: This study offers useful clues about the effectiveness of mindfulness interventions in the classroom in enhancing sense of belonging to a community, attention grounded in bodily sensations, and academic self-efficacy. Preregistration: This study is not preregistered.

8.
Front Psychol ; 14: 1307467, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38259544

RESUMO

The perception of material properties, which refers to the way in which individuals perceive and interpret materials through their sensory experiences, plays a crucial role in our interaction with the environment. Affordance, on the other hand, refers to the potential actions and uses that materials offer to users. In turn, the perception of the affordances is modulated by the aesthetic appreciation that individuals experience when interacting with the environment. Although material perception, affordances, and aesthetic appreciation are recognized as essential to fostering sustainability in society, only a few studies have investigated this subject matter systematically and their reciprocal influences. This scarcity is partially due to the challenges offered by the complexity of combining interdisciplinary topics that explore interactions between various disciplines, such as psychophysics, neurophysiology, affective science, aesthetics, and social and environmental sciences. Outlining the main findings across disciplines, this review highlights the pivotal role of material perception in shaping sustainable behaviors. It establishes connections between material perception, affordance, aesthetics, and sustainability, emphasizing the need for interdisciplinary research and integrated approaches in environmental psychology. This integration is essential as it can provide insight into how to foster sustainable and durable changes.

9.
J Clin Med ; 12(16)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37629405

RESUMO

Home confinement during the COVID-19 outbreak had psychological effects that continue to be explored by researchers. This study investigated factors influencing the mental health of mothers caring for special needs children in Italy's first lockdown. Specifically, we investigated the relationships between emotional states of depression, anxiety, stress, perceived distress related to home confinement, coping strategies, and other contextual variables (such as opportunities for distance learning and remote working) in a group of 68 mothers of children with special needs and 68 matched mothers of typically developing children. Data from an online survey showed no significant difference between the two groups. However, the research revealed that being a remote worker was a significant predictor of reduced stress in mothers of children with special needs, while distance learning was a significant predictor of reduced stress in mothers of typically developing children. In addition, the study found that hyperarousal symptoms were predictive of stress in mothers of children with special needs, while intrusive thoughts and avoidance coping were predictive of stress in mothers of typically developing children. In conclusion, further research is needed to develop effective support and intervention strategies for families with children with special needs and to deeply investigate the impact of flexible work arrangements and social aid on the mental health of mothers in non-emergency settings.

10.
Front Psychol ; 14: 1125066, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37008850

RESUMO

Interaction with the environment requires us to predict the potential reward that will follow our choices. Rewards could change depending on the context and our behavior adapts accordingly. Previous studies have shown that, depending on reward regimes, actions can be facilitated (i.e., increasing the reward for response) or interfered (i.e., increasing the reward for suppression). Here we studied how the change in reward perspective can influence subjects' adaptation strategy. Students were asked to perform a modified version of the Stop-Signal task. Specifically, at the beginning of each trial, a Cue Signal informed subjects of the value of the reward they would receive; in one condition, Go Trials were rewarded more than Stop Trials, in another, Stop Trials were rewarded more than Go Trials, and in the last, both trials were rewarded equally. Subjects participated in a virtual competition, and the reward consisted of points to be earned to climb the leaderboard and win (as in a video game contest). The sum of points earned was updated with each trial. After a learning phase in which the three conditions were presented separately, each subject performed 600 trials testing phase in which the three conditions were randomly mixed. Based on the previous studies, we hypothesized that subjects could employ different strategies to perform the task, including modulating inhibition efficiency, adjusting response speed, or employing a constant behavior across contexts. We found that to perform the task, subjects preferentially employed a strategy-related speed of response adjustment, while the duration of the inhibition process did not change significantly across the conditions. The investigation of strategic motor adjustments to reward's prospect is relevant not only to understanding how action control is typically regulated, but also to work on various groups of patients who exhibit cognitive control deficits, suggesting that the ability to inhibit can be modulated by employing reward prospects as motivational factors.

11.
Front Hum Neurosci ; 17: 1106298, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36845879

RESUMO

Goal-oriented actions often require the coordinated movement of two or more effectors. Sometimes multi-effector movements need to be adjusted according to a continuously changing environment, requiring stopping an effector without interrupting the movement of the others. This form of control has been investigated by the selective Stop Signal Task (SST), requiring the inhibition of an effector of a multicomponent action. This form of selective inhibition has been hypothesized to act through a two-step process, where a temporary global inhibition deactivating all the ongoing motor responses is followed by a restarting process that reactivates only the moving effector. When this form of inhibition takes place, the reaction time (RT) of the moving effector pays the cost of the previous global inhibition. However, it is poorly investigated if and how this cost delays the RT of the effector that was required to be stopped but was erroneously moved (Stop Error trials). Here we measure the Stop Error RT in a group of participants instructed to simultaneously rotate the wrist and lift the foot when a Go Signal occurred, and interrupt both movements (non-selective Stop version) or only one of them (selective Stop version) when a Stop Signal was presented. We presented this task in two experimental conditions to evaluate how different contexts can influence a possible proactive inhibition on the RT of the moving effector in the selective Stop versions. In one context, we provided the foreknowledge of the effector to be inhibited by presenting the same selective or non-selective Stop versions in the same block of trials. In a different context, while providing no foreknowledge of the effector(s) to be stopped, the selective and non-selective Stop versions were intermingled, and the information on the effector to be stopped was delivered at the time of the Stop Signal presentation. We detected a cost in both Correct and Error selective Stop RTs that was influenced by the different task conditions. Results are discussed within the framework of the race model related to the SST, and its relationship with a restart model developed for selective versions of this paradigm.

12.
J Neuroinflammation ; 9: 206, 2012 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-22913567

RESUMO

BACKGROUND: The pleiotropic pro-inflammatory cytokine Interleukin (IL)-18 has been proposed to play a role in schizophrenia, since elevated circulating levels of its protein and altered frequencies of genetic variants in its molecular system are reported in schizophrenic patients. METHODS: We analyzed 77 patients with schizophrenia diagnosis (SCZ) and 77 healthy control subjects (HC) for serum concentration of both IL-18 and its natural inhibitor, the IL-18 binding protein (IL-18BP). RESULTS: We confirmed that serum levels of total IL-18 are significantly increased in SCZ, as compared to HC. However, due to a highly significant increase in levels of circulating IL-18BP in SCZ, as compared to HC, the levels of free, bioactive IL-18 are not significantly different between the two groups. In addition, the relationships between the levels of IL-18 and its inhibitor, as well as between the two molecules and age appear dissimilar for SCZ and HC. In particular, the elevated levels of IL-18BP, likely a consequence of the body's attempt to counteract the early prominent inflammation which characterizes schizophrenia, are maintained in earlier and later stages of the disease. However, the IL-18BP elevation appears ineffective to balance the IL-18 system in younger SCZ patients, while in older patients the levels of circulating bioactive IL-18 are comparable to those of HC, if not lower. CONCLUSIONS: In conclusion, these findings indicate that the IL-18 system is perturbed in schizophrenia, supporting the idea that this pro-inflammatory cytokine might be part of a pathway of genetic and environmental components for vulnerability to the disease.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/sangue , Interleucina-18/sangue , Esquizofrenia/sangue , Adulto , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esquizofrenia/epidemiologia , Adulto Jovem
13.
Brain Topogr ; 25(4): 389-98, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22367586

RESUMO

Brain functional and psychophysical studies have clearly demonstrated that visual motion perception relies on the activity of the middle temporal complex (hMT+). However, recent studies have shown that hMT+ seems to be also activated during tactile motion perception, suggesting that this visual extrastriate area is involved in the processing and integration of motion, irrespective of the sensorial modality. In the present study, we used repetitive transcranial magnetic stimulation (rTMS) to assess whether hMT+ plays a causal role in tactile motion processing. Blindfolded participants detected changes in the speed of a grid of tactile moving points with their finger (i.e. tactile modality). The experiment included three different conditions: a control condition with no TMS and two TMS conditions, i.e. hMT+-rTMS and posterior parietal cortex (PPC)-rTMS. Accuracies were significantly impaired during hMT+-rTMS but not in the other two conditions (No-rTMS or PPC-rTMS), moreover, thresholds for detecting speed changes were significantly higher in the hMT+-rTMS with respect to the control TMS conditions. These findings provide stronger evidence that the activity of the hMT+ area is involved in tactile speed processing, which may be consistent with the hypothesis of a supramodal role for that cortical region in motion processing.


Assuntos
Percepção de Movimento/fisiologia , Lobo Temporal/fisiologia , Percepção do Tato/fisiologia , Tato/fisiologia , Estimulação Magnética Transcraniana , Adulto , Análise de Variância , Biofísica , Feminino , Dedos/inervação , Humanos , Masculino , Estimulação Física , Tempo de Reação , Adulto Jovem
14.
Brain Sci ; 11(5)2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33946423

RESUMO

Perseverative cognition (PC) is a transdiagnostic risk factor that characterizes both hypo-motivational (e.g., depression) and hyper-motivational (e.g., addiction) disorders; however, it has been almost exclusively studied within the context of the negative valence systems. The present study aimed to fill this gap by combining laboratory-based, computational and ecological assessments. Healthy individuals performed the Probabilistic Reward Task (PRT) before and after the induction of PC or a waiting period. Computational modeling was applied to dissociate the effects of PC on reward sensitivity and learning rate. Afterwards, participants underwent a one-week ecological momentary assessment of daily PC occurrence, as well as anticipatory and consummatory reward-related behavior. Induction of PC led to increased response bias on the PRT compared to waiting, likely due to an increase in learning rate but not in reward sensitivity, as suggested by computational modeling. In daily-life, PC increased the discrepancy between expected and obtained rewards (i.e., prediction error). Current converging experimental and ecological evidence suggests that PC is associated with abnormalities in the functionality of positive valence systems. Given the role of PC in the prediction, maintenance, and recurrence of psychopathology, it would be clinically valuable to extend research on this topic beyond the negative valence systems.

15.
Neuroimage ; 49(3): 2717-27, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19878728

RESUMO

Traditional views of multisensory integration emphasise the advantage of stimulating or attending to different senses at one single spatial location. We challenge this view demonstrating that in-parallel processing of two sensory modalities can be more efficient when attention is spatially divided rather than focused. We asked subjects to monitor simultaneously vision and audition either at one location (focused attention) or in the two opposite hemifields (divided attention) or to monitor one single modality at one or two locations. Behavioural results demonstrated that the costs of monitoring two modalities, versus one modality, decrease when spatial attention is divided between two separate locations compared with focused attention. Neuroimaging data revealed increased activity in the posterior-parietal cortex (PPC) when monitoring two modalities at different locations, while no specific region was recruited in the focused attention conditions. We suggest that supramodal control and the integration of spatial representations hinders the selection of independent sensory streams when attention is spatially focused, while a greater exploitation of modality-specific resources and the engagement of PPC allows in-parallel processing when attention is spatially divided.


Assuntos
Atenção/fisiologia , Mapeamento Encefálico , Encéfalo/fisiologia , Estimulação Acústica , Adulto , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Estimulação Luminosa , Adulto Jovem
16.
Psychiatry Res Neuroimaging ; 295: 111020, 2020 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-31790922

RESUMO

Perseverative cognition (i.e. rumination and worry) describes intrusive, uncontrollable, repetitive thoughts. These negative affective experiences are accompanied by physiological arousal, as if the individual were facing an external stressor. Perseverative cognition is a transdiagnostic symptom, yet studies of neural mechanisms are largely restricted to specific clinical populations (e.g. patients with major depression). The present study applied activation likelihood estimation (ALE) meta-analyses to 43 functional neuroimaging studies of perseverative cognition to elucidate the neurobiological substrates across individuals with and without psychopathological conditions. Task-related and resting state functional connectivity studies were examined in separate meta-analyses. Across task-based studies, perseverative cognition engaged medial frontal gyrus, cingulate gyrus, insula, and posterior cingulate cortex. Resting state functional connectivity studies similarly implicated posterior cingulate cortex together with thalamus and anterior cingulate cortex (ACC), yet the involvement of ACC distinguished between perseverative cognition in healthy controls (HC) and clinical groups. Perseverative cognition is accompanied by the engagement of prefrontal, insula and cingulate regions, whose interaction may support the characteristic conjunction of self-referential and affective processing with (aberrant) cognitive control and embodied (autonomic) arousal. Within this context, ACC engagement appears critical for the pathological expression of rumination and worry.


Assuntos
Encéfalo/diagnóstico por imagem , Giro do Cíngulo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Ruminação Cognitiva/fisiologia , Adulto , Nível de Alerta/fisiologia , Encéfalo/fisiopatologia , Cognição/fisiologia , Feminino , Giro do Cíngulo/fisiopatologia , Humanos , Masculino
17.
Psychiatry Res Neuroimaging ; 281: 107-116, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-30290286

RESUMO

Generalized anxiety disorder (GAD) has excessive anxiety and uncontrollable worry as core symptoms. Abnormal cerebral functioning underpins the expression and perhaps pathogenesis of GAD:. Studies implicate impaired communication between the amygdala and the pre-frontal cortex (PFC). Our aim was to longitudinally investigate whether such network abnormalities are spatially restricted to this circuit or if the integrity of functional brain networks is globally disrupted in GAD. We acquired resting-state functional magnetic resonance imaging data from 16 GAD patients and 16 matched controls at baseline and after 1 year. Using network modeling and graph-theory, whole-brain connectivity was characterized from local and global perspectives. Overall lower global efficiency, indicating sub-optimal brain-wide organization and integration, was present in patients with GAD compared to controls. The amygdala and midline cortices showed higher betweenness centrality, reflecting functional dominance of these brain structures. Third, lower betweenness centrality and lower degree emerged for PFC, suggesting weakened inhibitory control. Overall, network organization showed impairments consistent with neurobiological models of GAD (involving amygdala, PFC, and cingulate cortex) and further pointed to an involvement of temporal regions. Such impairments tended to progress over time and predict anxiety symptoms. A graph-analytic approach represents a powerful approach to deepen our understanding of GAD.


Assuntos
Tonsila do Cerebelo/diagnóstico por imagem , Transtornos de Ansiedade/diagnóstico por imagem , Lobo Frontal/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Adulto , Tonsila do Cerebelo/fisiopatologia , Transtornos de Ansiedade/fisiopatologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiopatologia , Feminino , Lobo Frontal/fisiopatologia , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiopatologia
18.
Neuropsychologia ; 45(14): 3351-5, 2007 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-17688892

RESUMO

Previous findings suggest that planning an action "backward-primes" perceptual dimension related to this action: planning a grasp facilitates the processing of visual size information, while planning a reach facilitates the processing of location information. Here we show that dimensional priming of perception through action occurs even in the absence of active action planning. Subjects watched video clips showing a grasping or reaching action before detecting size- or location-defined deviants in visual stimulus sequences. Size deviants were detected faster after seeing a grasp and location deviants were detected faster after seeing a reach. This supports the assumption that perceptual codes and action plans share a common representational medium, and that "attention to action" controls "attention to stimuli".


Assuntos
Atenção/fisiologia , Processos Mentais , Destreza Motora/fisiologia , Observação/métodos , Adulto , Análise de Variância , Feminino , Humanos , Intenção , Masculino , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa , Tempo de Reação/fisiologia
19.
Exp Psychol ; 54(2): 89-98, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17472092

RESUMO

Humans are fundamentally limited in processing information from the outside world. This is particularly evident in the attentional blink (AB), the impaired ability to identify the second of two targets presented in close succession. We report findings from three experiments showing that the AB is significantly reduced when observers are set to achieve one single goal (reporting combinations of the two targets) instead of separate goals (reporting the two targets). This finding raises questions about the nature of AB, and suggests that processes involved in goal-switching must be taken into account by theories of the AB phenomenon.


Assuntos
Atenção , Piscadela , Objetivos , Adulto , Feminino , Humanos , Masculino
20.
Behav Brain Res ; 173(1): 30-8, 2006 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-16857276

RESUMO

Several studies on cross-modal attention showed that remapping processes between sensory modalities occur in the spatial orienting of attention. One hypothesis that accounts for such links is that spatial attention operates upon representations of common locations in the external space. However, convincing evidence only exists for cross-modal links in spatial orienting, leaving the dynamics of these effects unexplored. Four experiments were designed to cope with this issue by having participants being involved in an endogenous orienting task to visual and auditory target stimuli. Targets on invalid trials were embedded into two different kinds of sequences of stimuli: (1) long sequences, wherein three valid trials in one modality preceded the invalid trial in the other modality; (2) short sequences, wherein only one valid trial in one modality preceded the invalid trial in the other modality. Results revealed modality-specific meridian effects in the short sequences, and a significant decrement of the modality-specific meridian effect in the long sequences. The results of these experiments indicate that cross-modal links in visual and auditory spatial attention are based on representations of common locations in the external space across sensory modalities. Moreover, the results strongly support the hypothesis that representations of space are dynamically built and updated according to task demands.


Assuntos
Atenção/fisiologia , Percepção Auditiva/fisiologia , Orientação/fisiologia , Percepção Espacial/fisiologia , Estimulação Acústica , Adulto , Humanos , Estimulação Luminosa , Valores de Referência , Integração de Sistemas
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