Rapid detection and response to visual threats are critical for survival in animals.The amygdala(AMY)is hypothesized to be involved in this process,but how it interacts with the visual system to do this remains unclea...Rapid detection and response to visual threats are critical for survival in animals.The amygdala(AMY)is hypothesized to be involved in this process,but how it interacts with the visual system to do this remains unclear.By recording flash-evoked potentials simultaneously from the superior colliculus(SC),lateral posterior nucleus of the thalamus,AMY,lateral geniculate nucleus(LGN)and visual cortex,which belong to the cortical and subcortical pathways for visual fear processing,we investigated the temporal relationship between these regions in visual processing in rats.A quick flash-evoked potential(FEP)component was identified in the AMY.This emerged as early as in the LGN and was approximately 25 ms prior to the earliest component recorded in the SC,which was assumed to be an important area in visual fear.This quick P1 component in the AMY was not affected by restraint stress or corticosterone injection,but was diminished by RU38486,a glucocorticoid receptor blocker.By injecting a monosynaptic retrograde AAV tracer into the AMY,we found that it received a direct projection from the retina.These results confirm the existence of a direct connection from the retina to the AMY,that the latency in the AMY to flashes is equivalent to that in the sensory thalamus,and that the response is modulated by glucocorticoids.展开更多
基金the National Key Research and Development Program of China(2018YFA0108503)the National Natural Science Foundation of China(81760251 and 81560234)the Yunnan Provincial Natural Science Foundation(2018FB118 and KKSY201626001).
文摘Rapid detection and response to visual threats are critical for survival in animals.The amygdala(AMY)is hypothesized to be involved in this process,but how it interacts with the visual system to do this remains unclear.By recording flash-evoked potentials simultaneously from the superior colliculus(SC),lateral posterior nucleus of the thalamus,AMY,lateral geniculate nucleus(LGN)and visual cortex,which belong to the cortical and subcortical pathways for visual fear processing,we investigated the temporal relationship between these regions in visual processing in rats.A quick flash-evoked potential(FEP)component was identified in the AMY.This emerged as early as in the LGN and was approximately 25 ms prior to the earliest component recorded in the SC,which was assumed to be an important area in visual fear.This quick P1 component in the AMY was not affected by restraint stress or corticosterone injection,but was diminished by RU38486,a glucocorticoid receptor blocker.By injecting a monosynaptic retrograde AAV tracer into the AMY,we found that it received a direct projection from the retina.These results confirm the existence of a direct connection from the retina to the AMY,that the latency in the AMY to flashes is equivalent to that in the sensory thalamus,and that the response is modulated by glucocorticoids.
