Applying near-infrared spectroscopy (nirs)

Over recent decades, much has been learned about the perceptual capacity that enables infants to recognize and understand language. However, not until very recently have the neural mechanisms that are the substance of language learning been investigated. A recently developed optical imaging technique called near-infrared spectroscopy (NIRS) shows promise for being an acceptable alternative to invasive imaging techniques. NIRS measures correlates of neural activity by assessing hemoglobin concentration changes in the infant brain. The research presented here investigates neural activation in the left temporal and occipital cortex regions during exposure to speech and visual stimuli. As hypothesized, hemodynamic reaction was observed in both areas. Results indicate a significant activation in response to speech in the left temporal region, and an intriguing difference between uni- and bi-modally presented speech stimuli. These results have interesting implications for future multimodal studies of infant speech perception.