Investigação da neuroplasticidade funcional no cérebro humano com espectroscopia no infravermelho próximo

Author(s)

Sérgio Luiz Novi Junior

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Instituto de Física Gleb Wataghin
• Defense date: 2022-03-17

Examining board members

Rickson Coelho Mesquita; Mônica Alonso Cotta; Romis Ribeiro de Faissol Attux; Ana Alexandra Caldas Osório; Mamadou Diop

• Advisor: Rickson Coelho Mesquita

Abstract

This thesis describes a robust methodology to investigate human brain plasticity with functional near-infrared spectroscopy (fNIRS). fNIRS is a promising optical neuroimaging technique that employs near-infrared light to probe functional brain activity continuously and noninvasively. Owing to its main features, such as portability and versatility, fNIRS holds great potential to assess a variety of populations under different conditions. Although promising, fNIRS suffers from low signal-tonoise ratio, which ultimately leads to lack of reproducibility at the individual level. The low intra-subject reproducibility limits the investigation of cerebral plasticity to group studies. In this context, we started our work by demonstrating the ability of fNIRS to probe cerebral plasticity at the group level. We showed fundamental aspects of natural early human brain development within the first year of life. Our fNIRS results evidenced brain specialization from full-term and preterm born infants and a delayed maturation in the brain of preterm group that was present even after one year of life. After showing the feasibility of fNIRS to elucidate brain plasticity mechanisms over group studies, we moved forward by developing robust methods to address the main confounding factors of fNIRS: motion artifacts, lack of anatomical spatial information, and systemic physiological contamination. Overall, we show that the fNIRS technique can provide highly reproducible results at the individual level for data acquired with block-designed experiments and during resting state as long as the data is analyzed correctly. We finalize this thesis by outlining our proposed data analysis pipeline for both resting-state and task-based experimental protocols, which we believe should be adopted and is the main contribution of this work. In conclusion, this thesis opens new directions to elucidate the main mechanisms of human brain plasticity continuously and noninvasively over longitudinal studies at the group and individual levels (AU)

• FAPESP's process: 19/21962-1 - Investigation of neuroplasticity in the human brain with near-infrared spectroscopy
• Grantee: Sergio Luiz Novi Junior
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)