Neuroscience 2024 NIRS fNIRS NIRx Publication
09/07/2024 at 03:07:00
Author: Jackson Cionek
09/07/2024 at 03:07:00
Author: Jackson Cionek
Detection of Emotional Sensitivity Using fNIRS Based Dynamic Functional Connectivity
Pode-se usar o EEG para analisar MicroStates que representam configurações breves e recorrentes da atividade elétrica cerebral, enquanto o NIRS pode monitorar a conectividade funcional e a oxigenação cerebral. Adicionalmente, a medição de íons de cálcio intracelulares poderia fornecer insights sobre a atividade neuronal em resposta a estímulos emocionais.
Possíveis experimentos:Integração Multimodal: Comparar como MicroStates do EEG e estados de conectividade do NIRS co-ocorrem durante a exposição a estímulos emocionais.
Correlação com Íons de Cálcio: Investigar a relação entre alterações nos níveis de íons de cálcio e as mudanças nos MicroStates do EEG/NIRS durante tarefas que envolvem tomada de decisão emocional.
Modelagem Preditiva: Desenvolver modelos que integrem dados de EEG, NIRS, e cálcio para prever a sensibilidade emocional e a resiliência em estudantes de enfermagem e profissionais já registrados.
Essas abordagens podem abrir caminhos para intervenções mais personalizadas e eficazes no treinamento de habilidades emocionais em contextos profissionais.
Ativação Neuronal: Quando neurônios em uma área específica do cérebro são ativados, seja por pensamentos, sensações, ou movimentos, eles aumentam o consumo de oxigênio e glicose para manter sua atividade.
Sinalização Química e Celular: A atividade neuronal elevada leva à liberação de vários metabólitos, como dióxido de carbono, íons de hidrogênio, adenosina, e óxido nítrico. Além disso, neurônios e células gliais (como astrócitos) liberam neurotransmissores e outros mediadores que sinalizam a necessidade de mais sangue.
Resposta Vascular: Esses sinais resultam em vasodilatação, ou seja, o alargamento dos vasos sanguíneos locais. A vasodilatação aumenta o fluxo sanguíneo para a região ativa, proporcionando mais oxigênio e glicose. Este aumento do fluxo sanguíneo é conhecido como hiperemia funcional.
Naturalistic Environments
With the advent of portable and wearable solutions, in addition to its intrinsic performance in the presence of movements, fNIRS is currently the ideal solution for studies that intend to evaluate cortical actitiy within naturalistic environments.
Cognitive States
fNIRS adds another dimension to studies investigating cognitive functions and mental states, since it is a portable technique not too sensitive to motion artifacts. Attention processes, inhibition mechanisms, and working memory, as well as other cognitive states, may be studied in natural environments with a fast setup preparation.
Motor Execution
Motor execution and fine movements depend on coordinated action of brain function and peripheral muscles. Its portability, ease of use in natural environments, and compatibility with bioelectric measures make fNIRS an optimal choice for studies investigating motor execution.
Emotions
Near-infrared spectroscopy is non-invasive and particularly well suited for evaluating activity in the prefrontal cortex, one of the regions involved in emotional processing. More specific areas related to emotional processing, such as the frontopolar cortex, are easily accessible for measurements by NIRS, making the technique particularly suited to explore the emotional domain.
Social Interaction
The ability of fNIRS to measure two or more subjects simultaneously, enables researchers to study cortical activity in response to social interaction. This way, a new dimension is added to studies investigating topics such as empathy, competitive and cooperative tasks, mother-child interactions and truth telling.
Speech and Language
Realistic experiments involve verbalized speech. As such, they should account for the muscle movements that are required for this process, and the eventual artifacts that these may cause. The robustness of fNIRS in the presence of muscle movements as well as its portability in comparison to other imaging techniques, render this technology a very promising tool for studying speech and language under a great variety of conditions.
Connectivity
fNIRS brings connectivity studies to a new level. The hyperscanning modality enables both online feedback as well as offline analysis regarding within- and between-subjects connectivity. In addition to that, fNIRS fast sampling rate for hemodynamic states allows for a quick update rate of connectivity feedback, resulting into enhanced subject engagement.
Developmental Changes
The portability of fNIRS, its performance in presence of general movements and the feasibility it offers in exploring cortical responses in social environments, represent the greatest advantages for studies on brain functional changes during development of infants and children.
Infant
Infant monitoring is based on continuous measurements of cortical activity within a population that may be characterized by its constant movement. The low sensitivity of fNIRS to motion artifacts make this technique an ideal choice for studies intended to explore the many unknown features of the infant brain.
Neuroeconomics
A key interest of neuroeconomics research is value-based decision making, in which the prefrontal lobe is an important player. Although prefrontal activity has been explored with fMRI, the restricted environment does impose a limit to the number of applications that can be explored. fNIRS may represent a conspicuous improvement to the field, as it enables outdoor measurements that can be combined with simultaneous Eye-Tracking.
Somatosensory
fNIRS determines changes in hemoglobin oxygenation in the human head non-invasively, and has the advantage of being more robust to motion artifacts than fMRI. In addition, the application of fNIRS is more convenient for somatosensory research, especially when measuring patients with chronic pain, as measurements can take place on a more comfortable bench compared to the MR scanner bench.
Multi-modal
In order to render measurements more robust, information may be provided by different modalities. Many groups appreciate multi-modal applications with fNIRS. Typical combinations are fNIRS and EEG, Eye-Tracking or fMRI, but tDCS and TMS have also been applied to concurrently modulate brain activity.
Visual Stimulation Auditory System
As fNIRS measurements are characterized by silent operations, innumerous possibilities of studies intended to explore cortical activation in the presence of controlled sounds can be achieved. Besides a better understanding of auditory processes in the brain, this may facilitate critical improvements on current solutions for cochlear implants.
Brain-Computer Interface (BCI)
Given its great performance in the presence of muscle movements and the possibility of setting up measurements in realistic environments, fNIRS presents itself as an ideal candidate for the acquisition of cortical signals as reliable and representative inputs for Brain-Computer Interface investigations.
Event-Related Optical Signal
fNIRS is potentially the only imaging method that may be capable to measure both hemodynamics and neuronal activity. The Event-Related Optical Signal, caused by changes in light scattering from activated neurons, is observable when employing high frequency sampling with fNIRS.