Collision-sensitive neurons in the optic tectum of the bullfrog, Rana catesbeiana.

Content Provider	Semantic Scholar
Author	Nakagawa, Hideki Hongjian, Kang
Copyright Year	2010
Abstract	In this study, we examined the neuronal correlates of frog collision avoidance behavior. Single unit recordings in the optic tectum showed that 11 neurons gave selective responses to objects approaching on a direct collision course. The collision-sensitive neurons exhibited extremely tight tuning for collision bound trajectories with mean half-width at half height values of 0.8 and 0.9° (n = 4) for horizontal and vertical deviations, respectively. The response of frog collision-sensitive neurons can be fitted by a function that simply multiplies the size dependence of its response, e(-αθ(t)), by the image's instantaneous angular velocity θ'(t). Using fitting analysis, we showed that the peak firing rate always occurred after the approaching object had reached a constant visual angle of 24.2 ± 2.6° (mean ± SD; n = 8), regardless of the approaching velocity. Moreover, a linear relationship was demonstrated between parameters l/v (l: object's half-size, v: approach velocity) and time-to-collision (time difference between peak neuronal activity and the predicted collision) in the 11 collision-sensitive neurons. In addition, linear regression analysis was used to show that peak firing rate always occurred after the object had reached a constant angular size of 21.1° on the retina. The angular thresholds revealed by both theoretical analyses were comparable and showed a good agreement with that revealed by our previous behavioral experiments. This strongly suggests that the collision-sensitive neurons of the frog comprise a threshold detector, which triggers collision avoidance behavior.
Starting Page	1071
Ending Page	1074
Page Count	4
File Format	PDF HTM / HTML
Alternate Webpage(s)	http://jn.physiology.org/content/jn/104/5/2487.full.pdf
PubMed reference number	20810689v1
Alternate Webpage(s)	https://doi.org/10.1152/jn.01055.2009
DOI	10.1152/jn.01055.2009
Journal	Journal of neurophysiology
Volume Number	104
Issue Number	5
Language	English
Access Restriction	Open
Subject Keyword	Anura Corpora quadrigemina, superior colliculus Detectors Eye Neurons Physical object Precipitating Factors REM Sleep Behavior Disorder Rana Rana catesbeiana Regression Analysis Retina Seizures Tectum Mesencephali collision tectum cellular component width
Content Type	Text
Resource Type	Article