Abstract
Spatial awareness is often intentional, arising from deliberate movements towards a target, while at other times it emerges from unexpected motion in the scene. While navigating the environment, animals must differentiate the spatial cues generated by self-motion from object movements that originate externally. To reveal the neural basis of this ability, we examined the midbrain superior colliculus (SC), which contains multiple egocentric maps of sensorimotor space. By simulating whisker-guided navigation through a dynamic landscape, we discovered a transient neural response that selectively emerged for unexpected, externally generated tactile motion. This transient response only emerged when external motion engaged different whiskers, arguing that sensorimotor expectations are specific to a somatotopic location. When external motion engaged the same whiskers, neurons shifted their spike timing to match self-generated spatial features. Thus, representations based on the timing of self-generated cues may surpass the spatial acuity of the whisker array. In conclusion, the SC contains complementary rate and temporal codes to differentiate external from self-generated tactile features.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
Additional supplementary figures and revised main text.
