ISSN : 1226-9654
얼굴의 정보가 전체적으로 처리되는가 혹은 국소적으로 처리되는가 하는 것은 얼굴인식과 관련된 중요한 논쟁 중의 하나이다. 최근에는 전체적 처리와 국소적 처리가 동시에 이루어지며, 각기 다른 경로를 통해 이루어진다는 주장이 제기된 바 있다. 본 연구에서는 얼굴 정보에 대한 이러한 이중경로처리설을 확인하기 위하여, 형태정보처리 경로의 시각 세포들이 최적으로 반응하는 자극속성을 반영한 방사주파수 합성얼굴을 이용하여 얼굴의 윤곽과 국소정보에 대한 선택적 뇌 활성화의 차이를 fMRI측정을 통하여 살펴보았다. 실험 1에서는 얼굴의 윤곽과 국소정보 모두에 대하여 FFA 영역에서의 활성화를 관찰하였다. 주목할 점은, 국소정보에 비하여 윤곽정보에 대한 FFA에서의 활성화가 더 강하게 관찰된 것이다. 실험 2에서는 얼굴의 윤곽정보에 대한 전체적 처리가 인출과정보다는 부호화과정에 관여함을 관찰하였고, 국소정보의 부호화 조건에서는 전전두엽(BA 10)과 대상회(BA 32)에서의 강한 활성화를 관찰하였다. 이러한 결과들은, 얼굴인식이 이중경로를 통해 이루어진다는 연구들을 지지하는 증거로 해석되며, 얼굴의 윤곽정보는 상향처리를 통해, 국소정보는 하향처리를 통해 인식되는 것임을 시사한다.
One of the controversial issues on face recognition is whether faces are recognized as undifferentiated wholes or in terms of their constituent parts, namely, global vs local information processing for face recognition. However, it has been recently proposed that global coding and local processing constitute dual routes to face recognition. To investigate this dual routs processing hypothesis, we directly examined the selective activation of human brain areas with fMRI measurements to the synthetic face stimuli composed of radial frequency components, which had an advantage to easily separate the global contour and local basic feature information of face. In experiment 1, we found that FFA was activated to face contour and feature information. More importantly, it was observed that the strength of activation to contour information was higher than to feature information in FFA. In experiment 2, we also found that the global processing of face contour information was involved mainly in encoding processing, not in retrieval processing. Strong activations of the prefrontal region (BA10) and the cingulate gyrus (BA 32) were observed during encoding processing of face feature information. These results altogether add to our understanding of the characteristics of dual routes processing in face recognition. In addition, these results suggest that the contour information of face stimulus is processed through a bottom-up processing whereas the feature information is processed through a top-down processing.
(2003) 얼굴인식에 있어 방사주파수 정보의 뇌 실재성,
(2000) Regional cerebral blood flow(rCBF) imaging of the facial conjunction effect.,
(2003) What are the routes to face recognition? , Oxford University Press
(1971) Models for the processing and identification of faces,
(1987) Visual properties of neurons in area V4 of the macaque sensitivity to stimulus form Journal of Neurophysiology,
(1995) The inverted face inversion effect in prosopagnosia evidence for mandatory, face-specific perceptual mechanisms,
(1998) What is "special" about face perception? ,
(1993) Selectivity for polar and Cartesian gratings in macaque visual cortex,
(1999) Can face recognition really be dissociated from object recognition?,
(1997) Becoming a "Greeble" expert: Exploring mechanisms for face recognition. ,
(2002) Unraveling mechanisms for expert object recognition: Bridging brain activity and behavior. ,
(2000) Expertise for cars and birds recruits brain areas involved in face recognition,
(1999) Activation of the middle fusiform "face area" increases with expertise in recognizing novel objects.,
(2001) Beyond localization:a dynamical dual route account of face recognition,
(1997) The fusiform face area: A module in human extrastriate cortex specialized for face perception.,
(2003) When is a face not a face? The effects of misorientation on mechani는 of face perception., Oxford University Press
(2001) Face processing occurs outside the fusiform ‘face area’ in autism evidence from functional MRI,
(1994) Role of attention in face encoding Journal of Experimental Psychology,
(1993) Parts and wholes in face recognition,
(2003) The holistic representation of faces Perception of faces, Oxford University Press
(1998) Detection and recognition of Radial Frequency Patterns,
(2002) Synthetic faces, face Cubes, and the geometry of Face Space. ,
(1969) Looking at upside-down faces,