TY - JOUR TI - Statistical structure of locomotion and its modulation by odors AU - Tao, Liangyu AU - Ozarkar, Siddhi AU - Beck, Jeffrey M AU - Bhandawat, Vikas A2 - Calabrese, Ronald L A2 - VijayRaghavan, K VL - 8 PY - 2019 DA - 2019/01/08 SP - e41235 C1 - eLife 2019;8:e41235 DO - 10.7554/eLife.41235 UR - https://doi.org/10.7554/eLife.41235 AB - Most behaviors such as making tea are not stereotypical but have an obvious structure. However, analytical methods to objectively extract structure from non-stereotyped behaviors are immature. In this study, we analyze the locomotion of fruit flies and show that this non-stereotyped behavior is well-described by a Hierarchical Hidden Markov Model (HHMM). HHMM shows that a fly's locomotion can be decomposed into a few locomotor features, and odors modulate locomotion by altering the time a fly spends performing different locomotor features. Importantly, although all flies in our dataset use the same set of locomotor features, individual flies vary considerably in how often they employ a given locomotor feature, and how this usage is modulated by odor. This variation is so large that the behavior of individual flies is best understood as being grouped into at least three to five distinct clusters, rather than variations around an average fly. KW - Markov model KW - olfaction KW - locomotion KW - behavior JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -