Neural bases of emotional face processing in infancy : a funcional near-infrared spectroscopy study

• Ano de defesa: 2017
• Autor(a) principal: Porto, Juliana Antola
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Pontifícia Universidade Católica do Rio Grande do Sul; Escola de Medicina; Brasil; PUCRS; Programa de Pós-Graduação em Medicina e Ciências da Saúde
• Palavras-chave em Português: Infants; Face Processing; Emotion; fNIRS; Maternal Anxiety; Lactentes; Processamento Facial; Emoção; Ansiedade Materna; CIENCIAS DA SAUDE::MEDICINA
• Link de acesso: http://tede2.pucrs.br/tede2/handle/tede/7867

The neural bases of facial emotion processing in infancy are largely unknown. The environmental factors that may impact facial processing and emotion recognition along the developmental course are also not clearly understood. However, early experiences, particularly involving consistent exposure to familiar caregiver faces, are believed to influence this course. The aim of this study was to investigate the neural correlates of infants’ emotional face processing using functional near-infrared spectroscopy (fNIRS), and examine the potential influence of infants’ early emotional experiences, indirectly measured by investigating maternal anxiety symptoms. Participants were 29 typically developing 5-monthold infants and their mothers, recruited from a community sample from the Boston greater area, MA, USA. Maternal anxiety was assessed using the trait component of the State-Trait Anxiety Inventory. Infants observed static visual images of a female model portraying happy and fearful expressions, while hemodynamic brain responses were measured using fNIRS. The oxyhemoglobin (oxyHb) and deoxyhemoglobin (deoxyHb) responses over frontal, parietal and temporal areas were compared for the emotional expressions in infants of mothers reporting low and high levels of anxiety symptoms. Results revealed a significant main effect of emotion (p=.022), driven by greater oxyHb concentration responses for happy compared to fearful faces. There was also a main effect of region (p=.013) induced by a significantly greater oxyHb concentration in temporal compared to frontal cortical regions (p=.031). Additionally, a significant three-way interaction between emotion, hemisphere and anxiety was observed (p=.037). Planned comparisons revealed that infants of high-anxious mothers showed significantly greater left hemispheric activation of oxyHb to happy faces when compared with right (p=.040) and left (p=.033) hemispheric activation of oxyHb to fearful faces. These findings possibly indicate that 5-month-olds can discriminate happy from fearful faces, evinced by the greater activation for the former. The greater activation in temporal as compared to frontal areas was discussed in relation to the ontogenesis of face processing and emotion recognition neural networks. The enhanced response to happy versus fearful faces observed in infants of high-anxious mothers can be related to the presumed altered emotional environment experienced by these infants, compared to that of infants of low-anxious mothers. Therefore, maternal anxiety levels appeared to moderate infants’ hemodynamic brain responses to emotional faces.