We focus on the neuronal mechanism of visual pattern recogination:
Hubel and Wiesel's discovery may have answered the question in the 1960s about how a simple line segment could be identified. Namely: the brain has prefabricated the corresponding detector for bars in different orientations and occurred at various locations. However, this simple strategy will encounter difficulties when the brain has to identify complicated graphics. Perhaps we can imagine that the brain precast detectors for combination of two bars. But what will it do for three bars or more complex shapes? Unfortunately, most real shapes are more complex than bars. It is just the beginning to identify the local bar orientation in the contour. The real challenge is how the visual system identifies a complete shapes using dispersed orientation information.
We are concentrating on how the visual cortex recognize shapes that are a little more complex than bars, such as how the brain identify a longer line, or an angle combined by two bars. To this end, we have established advanced behavioral and neurophysiological methods including electrode arrays, optical imaging, two-photon imaging and optical stimulation, to figure out the complicated neural circuits in the visual cortex.
1. Tang SM，Juusola, M , Intrinsic Activity in the Fly Brain Gates Visual Information during Behavioral Choices , PLoS ONE , 2011 , 5(12): e14455.
2. Tang SM, Wolf R, Xu SP, Heisenberg M , Visual pattern recognition in Drosophila is invariant for retinal position , Science , 2004 , 305, 1020-1022
3. Wang SP, Tang SM , Behavioral modification in choice process of Drosophila , Science in China , 2003 , Vol.46, pp.399-413
4. Tang SM, Guo AK , Choice behavior of Drosophila facing contradictory visual cues , Science , 2001 , 294, 1543-1547