3 research outputs found
Infants' brain responses to looming danger: Degeneracy of neural connectivity patterns
A fundamental property of most animals is the ability to see whether an object is approaching on a direct collision course and, if so, when it will collide. Using high-density electroencephalography in infants and a looming stimulus approaching under three different accelerations, we previously found how visual information for impending collision is sustained in the young human nervous system. In the present study, using longitudinal data on 25 infants at 4–5 months and 12–13 months, we show that infants’ looming-related brain activity is clearly localized in the visual cortex (V1) following retinotopic mapping, but is highly adaptive in its organization otherwise. Analyzing the orientation of electrical source flow, we provide evidence for a high degree of variability, spread across a relatively large area of the visual cortex. The findings reveal a highly dynamic functional organization, with connectivity patterns constantly emerging and changing in many different directions between trials. This suggests degeneracy of neural connectivity patterns through reentry principles, where neurons temporarily assemble to enable an appropriate looming response with the necessary precision
Development of visual motion perception for prospective control: Brain and behavioral studies in infants
During infancy, smart perceptual mechanisms develop allowing infants to judge time-space motion dynamics more efficiently with age and locomotor experience. This emerging capacity may be vital to enable preparedness for upcoming events and to be able to navigate in a changing environment. Little is known about brain changes that support the development of prospective control and about processes, such as preterm birth, that may compromise it. As a function of perception of visual motion, this paper will describe behavioral and brain studies with young infants investigating the development of visual perception for prospective control. By means of the three visual motion paradigms of occlusion, looming, and optic flow, our research shows the importance of including behavioral data when studying the neural correlates of prospective control
A high-density EEG study of differentiation between two speeds and directions of simulated optic flow in adults and infants
A high‐density EEG study was carried out to investigate cortical activity in response to forward and backward visual motion at two different driving speeds, simulated through optic flow. Participants were prelocomotor infants at the age of 4–5 months and infants with at least 3 weeks of crawling experience at the age of 8–11 months, and adults. Adults displayed shorter N2 latencies in response to forward as opposed to backward visual motion and differentiated significantly between low and high speeds, with shorter latencies for low speeds. Only infants at 8–11 months displayed similar latency differences between motion directions, and exclusively in response to low speed. The developmental differences in latency between infant groups are interpreted in terms of a combination of increased experience with self‐produced locomotion and neurobiological development. Analyses of temporal spectral evolution (TSE, time‐dependent amplitude changes) were also performed to investigate nonphase‐locked changes at lower frequencies in underlying neuronal networks. TSE showed event‐related desynchronization activity in response to visual motion for infants compared to adults. The poorer responses in infants are probably related to immaturity of the dorsal visual stream specialized in the processing of visual motion and could explain the observed problems in infants with differentiating high speeds of up to 50 km/h