Fear is an emotion that has powerful effects on behaviour and physiology across animal species. It is accepted that the amygdala has a central role in processing fear. However, it is less widely appreciated that distinct amygdala outputs and downstream circuits are involved in different types of fear. Data show that fear of painful stimuli, predators and aggressive members of the same species are processed in independent neural circuits that involve the amygdala and downstream hypothalamic and brainstem circuits. Here, we discuss data supporting multiple fear pathways and the implications of this distributed system for understanding and treating fear.
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Detection of neuronal defensive discharge information transmission and characteristics in periaqueductal gray double-subregions using PtNP/PEDOT:PSS modified microelectrode arrays
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This work evolved out of discussions initiated at the Janelia Conference 'Can New Tools Revolutionize Understanding of Hypothalamic Neural Circuits?' in October 2009 and was supported in part by funds from the European Molecular Biology Laboratory to C.G. and grants from Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP, no. 05/59286-4) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) to N.S.C.
The authors declare no competing financial interests.
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Gross, C., Canteras, N. The many paths to fear. Nat Rev Neurosci 13, 651–658 (2012). https://doi.org/10.1038/nrn3301
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