The brain’s orienting response: An event-related functional magnetic resonance imaging investigation

This study suggests that the brain’s response to novel sounds not only orients attention but also extracts their meaning to help guide appropriate actions.

Article Abstract

“An important function of the brain’s orienting response is to enable the evaluation of novel, environmental events in order to prepare for potential behavioral action. Here, we assessed the event-related hemodynamic (erfMRI) correlates of this phenomenon using unexpected (i.e., novel) environmental sounds presented within the context of an auditory novelty oddball paradigm. In ERP investigations of the novelty oddball, repetition of the identical novel sound leads to habituation of the novelty P3, an ERP sign of the orienting response. Repetition also leads to an enhancement of a subsequent positivity that appears to reflect the semantic analysis of the environmental sounds. In this adaptation for erfMRI recording, frequent tones were intermixed randomly with infrequent target tones and equally infrequent novel, environmental sounds. Subjects responded via speeded button press to targets. To assess habituation, some of the environmental sounds were repeated two blocks after their initial presentation. As expected, novel sounds and target tones led to activation of widespread, but somewhat different, neural networks. Contrary to expectation, however, there were no significant areas in which activation was reduced in response to the second compared to the first presentations of the novel sounds. Conversely, novel sounds relative to target tones engendered activity in the inferior frontal gyrus (BA 45) consistent with semantic analysis of these events. We conclude that a key concomitant of the orienting response is the extraction of meaning, therefore enabling one to determine the significance of the environmental perturbation and take appropriate goal-directed action.”

—Description from publisher

Article Access

Open Access

Friedman, D., Goldman, R., Stern, Y., & Brown, T. (2009). The brain’s orienting response: An event-related functional magnetic resonance imaging investigation. Human Brain Mapping, 30(4), 1144-1154. Open access: https://doi.org/10.1002/hbm.20587