TY - JOUR T1 - Biological action identification does not require early visual input for development JF - eneuro JO - eNeuro DO - 10.1523/ENEURO.0534-19.2020 SP - ENEURO.0534-19.2020 AU - Siddhart S. Rajendran AU - Davide Bottari AU - Idris Shareef AU - Kabilan Pitchaimuthu AU - Suddha Sourav AU - Nikolaus F. Troje AU - Ramesh Kekunnaya AU - Brigitte Röder Y1 - 2020/10/15 UR - http://www.eneuro.org/content/early/2020/10/15/ENEURO.0534-19.2020.abstract N2 - Visual input during the first years of life is vital for the development of numerous visual functions. While normal development of global motion perception seems to require visual input during an early sensitive period, the detection of biological motion (BM) does not seem to do so. A more complex form of BM processing is the identification of human actions. Here we tested whether identification rather than detection of BM is experience dependent. A group of human participants who had been treated for congenital cataracts (of up to 18 year duration, CC group) had to identify ten actions performed by human line figures. In addition they performed a coherent motion (CM) detection task, which required identifying the direction of coherent motion amidst the movement of random dots. As controls, developmental cataract reversal individuals (DC group) who had undergone the same surgical treatment as CC group were included. Moreover, normally sighted controls were tested both with vision blurred to match the visual acuity of CC individuals (vision matched (VM) group) and with full sight (sighted control (SC) group). The CC group identified biological actions with an extraordinary high accuracy (on average ∼85% correct) and was indistinguishable from the vision matched control group. By contrast, CM processing impairments of the CC group persisted even after controlling for visual acuity. These results in the same individuals demonstrate an impressive resilience of biological motion processing to aberrant early visual experience and at the same time a sensitive period for the development of coherent motion processing.Significance statement Biological motion is a crucial aspect of human vision, which has been shown to emerge early in human ontogeny. Here we report an astonishing high accuracy in identifying human actions in a unique group of individuals who had regained vision later in life (until the age of 18 years) after being treated for congenital cataracts. By contrast the same individuals were markedly impaired in another non-biological motion tasks requiring the detection of motion coherence in dot kinematograms, even after visual acuity impairments were taken into account. Thus, the present study demonstrates a remarkable resilience of complex biological motion processing capabilities such as the identification of human actions to aberrant early visual experience. ER -