Titulo Estágio
Brain activity in threat situations
Áreas de especialidade
Sistemas Inteligentes
Local do Estágio
DEI-FCTUC
Enquadramento
It has been proved that threat stimuli evoke a defensive response and trigger physiological reflexes affecting ongoing behaviour. In humans, some studies depicted diverse brain regions that activate under threatening stimuli; some of the cortical areas involved the premotor cortex, the pre-supplementary motor area, and the inferior frontal gyrus.
In most of these studies, the stimuli were images or videos presenting human reactions (face or body expressions) to a threat situation. Also, videos involving frightening animals have been used as visual stimuli. In all these cases, emotional responses are inherent to visual stimuli recognition and interpretation. Moreover, observing a scene on a monitor reduces the feeling of being in a threatening situation. Finally, part of these studies has used fMRI to identify the activation of brain areas. Still, despite a good spatial resolution, this method has a poor temporal resolution, limiting the study of fast responses.
Objetivo
In this study, it is proposed to use virtual reality videos involving the presentation of some unexpected flash shadows in the scene, looking to invoke a defensive reaction. The evoked cortical-brain activity will be studied by Electroencephalogram (EEG), warranting a good temporal resolution (in order of milliseconds). Here, it is expected to improve the knowledges about reflex reactions under threat situations, and the cortical connections involved.
Plano de Trabalhos - Semestre 1
1)Bibliography review (1 month): concepts related to visual evoked potential and signal processing must be reviewed.
2)Preparation of the virtual-reality stimuli video (1 1/2 months): this task may be implemented using Matlab & Simulink virtual reality apps.
3)Data acquisitions (1 1/2 months): it will be conducted with young, healthy volunteers. EEG will be recorded under the visual stimuli presentation.
4)Intermediate report elaboration and submission (1 month)
Plano de Trabalhos - Semestre 2
5)Data analysis (3 months): spatial, temporal, and spectral characteristics should be extracted from the collected EEG signals using Matlab.
6)Statistical analysis & time-space pattern recognition (1 month): implemented on the features obtained in task 4.
7)Final report elaboration and submission (2 months).
Condições
Secretária e recursos computacionais.
Orientador
Lorena Petrella
lorenapetrella@dei.uc.pt 📩