Chattering teeth is a bodily function in animals that occurs primarily in response to cold; the jaw muscles begin to shiver leading teeth to crash together. It may also occur as a result of bruxism where emotional stress causes the jaw movements. Certain medications can lead to teeth chattering as a side effect, especially antipsychotics and selective serotonin reuptake inhibitors.[1][2][3][4][5][6]
^Wiper, Susan M.; Semple, Stuart (October 2007). "The function of teeth chattering in male Barbary macaques (Macaca sylvanus)". American Journal of Primatology. 69 (10): 1179–1188. doi:10.1002/ajp.20434. PMID17358007. S2CID22306315.
^Lammers, J.H.C.M.; Kruk, M.R.; Meelis, W.; van der Poel, A.M. (May 1988). "Hypothalamic substrates for brain stimulation-induced attack, teeth-chattering and social grooming in the rat". Brain Research. 449 (1–2): 311–327. doi:10.1016/0006-8993(88)91046-3. PMID3395851. S2CID7907529.