Misperceptions of speed are accounted for by the responses of neurons in macaque cortical area MT.
نویسندگان
چکیده
In humans, the perceived speed of random dot patterns (RDP) moving within small apertures is faster than that of RDPs moving within larger apertures at the same physical speed. To investigate the neural basis of this illusion, we recorded the responses of direction- and speed-selective neurons in the middle temporal area (MT) of macaque monkeys to stimuli varying in size and speed. Our results show that the preferred speed of MT neurons is slower for smaller stimuli. This effect was larger for neurons preferring faster speeds, matching our psychophysical observation in human subjects that the magnitude of the misperception is larger at higher stimulus speeds. Our physiological data indicate that, across a population of speed-tuned neurons in MT, decreasing the size of a stimulus would shift the activity profile to neurons tuned for higher speeds. Modeling a labeled-line readout of this shifted profile, we show an increased apparent speed, in line with the psychophysical observations. This link strengthens the evidence for a causal role of area MT in speed perception. The systematic shift in tuning curves of single neurons with stimulus size might reflect a general mechanism for feature-mismatch illusions in visual perception.
منابع مشابه
Neurophysiol Mark M . Churchland , Nicholas J . Priebe and Stephen G . Lisberger Selectivity in Visual Areas MT and V 1 Comparison of the Spatial Limits on Direction
[PDF] [Full Text] [Abstract] , December 2, 2010; 10 (14): . J Vis Eugenie Roudaia, Patrick J. Bennett, Allison B. Sekuler and Karin S. Pilz Spatiotemporal properties of apparent motion perception and aging [PDF] [Full Text] [Abstract] , March , 2011; 105 (3): 1199-1211. J Neurophysiol Pinar Boyraz and Stefan Treue area MT Misperceptions of speed are accounted for by the responses of neurons...
متن کاملThe neural representation of speed in macaque area MT/V5.
Tuning for speed is one key feature of motion-selective neurons in the middle temporal visual area of the macaque cortex (MT, or V5). The present paper asks whether speed is coded in a way that is invariant to the shape of the moving stimulus, and if so, how. When tested with single sine-wave gratings of different spatial and temporal frequencies, MT neurons show a continuum in the degree to wh...
متن کاملResponses of primary somatosensory cortical neurons to controlled mechanical stimulation.
The results of psychophysical studies suggest that displacement velocity may contribute significantly to the sensation of subcortical somatosensory neurons. The cortical correlates of these phenomena, however, are not known. In the present study the responses of rapidly adapting (RA) neurons in the forelimb region of cat primary somatosensory cortex (SI) to controlled displacement of skin and h...
متن کاملBrief motion stimuli preferentially activate surround-suppressed neurons in macaque visual area MT
generally found that observers rely on whichever neurons are most informative about the stimulus to perform similar psychophysical tasks [6]. Here we show that the responses of neurons in the middle temporal (MT) area of macaque monkeys provide a simple resolution to this paradox. We find that surroundsuppressed MT neurons integrate motion signals relatively quickly, so that by comparison non-s...
متن کاملShort-latency category specific neural responses to human faces in macaque inferotemporal cortex
In this article I would present evidence to show that timing of the flow of neural signals within the ventral visual stream is a crucial part of the neural code for categorization of faces. We recorded the activity of 554 inferotemporal neurons from two macaque monkeys performing a fixation task. More than 1000 object images including human and non-primate animal faces were presented up to 10 t...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Journal of neurophysiology
دوره 105 3 شماره
صفحات -
تاریخ انتشار 2011