Spontaneous Spatial Mismatch Responses in the Sensory Cortex in Early Infancy

Whenever a perceived event violates expectations compared with an expected event, the cortical response to this event tends to be augmented. The increase in cortical responses signals a mismatch between expectation and observation. Mismatch patterns of neural activity have been repeatedly observed in adults, but their emergence and evolution in infancy are not well understood, since most prediction-inducing paradigms require learning the association or rule underpinning the expectation, thus conflating the violation response with the ability to learn. To address this shortcoming, this article reports a neuroimaging study with 2- to 6-month-olds that measured neural responses to the colocation (expected or matched) or dislocation (deviant or mismatch) of sounds and visual events. The results indicated that even in early infancy, the brain is sensitive to violations of expectation: Stimuli that deviated from expectation elicited stronger neural responses in these infants' sensory cortices than expected stimuli.