TY - JOUR

T1 - Orienting toward threat: Contributions of a subcortical pathway transmitting retinal afferents to the amygdala via the superior colliculus and pulvinar

AU - Koller, Kristin

AU - Rafal, Robert D.

AU - Platt, Adam

AU - Mitchell, Nicholas D.

N1 - Neural Routes to Awareness in Vision, Emotion and Action: A tribute to Larry Weiskrantz

PY - 2019/5

Y1 - 2019/5

N2 - Probabilistic diffusion tractography was used to provide the first direct evidence for a subcortical pathway from the retina to the amygdala, via the superior colliculus and pulvinar, that transmits visual stimuli signaling threat. A bias to orient toward threat was measured in a temporal order judgement saccade decision task, under monocular viewing, in a group of 19 healthy participants who also underwent diffusion weighted MR imaging. On each trial of the behavioural task a picture depicting threat was presented in one visual field and a competing non-threatening stimulus in the other. The onset interval between the two pictures was randomly varied and participants made a saccade toward the stimulus that they judged to have appeared first. The bias to orient toward threat was stronger when the threatening stimulus was in the temporal visual hemifield, suggesting that afferents via the retinotectal tract contributed to the bias. Probabalistic tractography was used to virtually dissect connections between the superior colliculus and the amygdala traversing the pulvinar. Individual differences in microstructure (fractional anisotropy) of the streamline predicted the magnitude of the bias to orient toward threat, providing supporting evidence for a functional role of the subcortical SC-amygdala pathway in processing threat in healthy humans.

AB - Probabilistic diffusion tractography was used to provide the first direct evidence for a subcortical pathway from the retina to the amygdala, via the superior colliculus and pulvinar, that transmits visual stimuli signaling threat. A bias to orient toward threat was measured in a temporal order judgement saccade decision task, under monocular viewing, in a group of 19 healthy participants who also underwent diffusion weighted MR imaging. On each trial of the behavioural task a picture depicting threat was presented in one visual field and a competing non-threatening stimulus in the other. The onset interval between the two pictures was randomly varied and participants made a saccade toward the stimulus that they judged to have appeared first. The bias to orient toward threat was stronger when the threatening stimulus was in the temporal visual hemifield, suggesting that afferents via the retinotectal tract contributed to the bias. Probabalistic tractography was used to virtually dissect connections between the superior colliculus and the amygdala traversing the pulvinar. Individual differences in microstructure (fractional anisotropy) of the streamline predicted the magnitude of the bias to orient toward threat, providing supporting evidence for a functional role of the subcortical SC-amygdala pathway in processing threat in healthy humans.

KW - Subcortical

KW - Threat

KW - DTI

KW - Saccades

KW - Temporal hemifield

KW - Amygdala

KW - Superior colliculus

KW - Pulvinar

U2 - 10.1016/j.neuropsychologia.2018.01.027

DO - 10.1016/j.neuropsychologia.2018.01.027

M3 - Article

VL - 128

SP - 78

EP - 86

JO - Neuropsychologia

JF - Neuropsychologia

SN - 0028-3932

ER -