Seeing what we know and understand: How knowledge shapes perception
- 710 Downloads
Expertise in object recognition, as in bird watching or X-ray specialization, is based on extensive perceptual experience and in-depth semantic knowledge. Although it has been shown that rich perceptual experience shapes elementary perception and higher level discrimination and identification, little is known about the influence of in-depth semantic knowledge on object perception and identification. By means of recording event-related brain potentials (ERPs), we show that the amount of knowledge acquired about initially unfamiliar objects modulates visual ERP components already 120 msec after object presentation, and causes gradual variations of activity in similar brain systems within a later timeframe commonly associated with meaning access. When perceptual analysis is made more difficult by blurring object pictures, knowledge has an even stronger effect on perceptual analysis and facilitates recognition. These findings demonstrate that in-depth knowledge not only affects involuntary semantic memory access, but also shapes perception by penetrating early visual processes traditionally held to be immune to such influences.
KeywordsKnowledge Condition Perceptual Analysis Global Field Power Knowledge Effect Unfamiliar Object
Unable to display preview. Download preview PDF.
- Barsalou, L. W. (1999). Perceptual symbol systems. Behavioral & Brain Sciences, 22, 577–660.Google Scholar
- Hopfinger, J. B., Luck, S. J., & Hillyard, S. A. (2004). Selective attention: Electrophysiological and neuromagnetic studies. In M. S. Gazzaniga (Ed.), The cognitive neurosciences (3rd ed., pp. 561–574). Cambridge, MA: MIT Press.Google Scholar
- Martin, A. (1998). The organization of semantic knowledge and the origin of words in the brain. In N. Jablonski & L. Aiello (Eds.), The origin and diversification of language (pp. 69–98). San Francisco: California Academy of Sciences.Google Scholar
- Talairach, J., & Tournoux, P. (1988). Co-planar stereotaxic atlas of the human brain. New York: Thieme.Google Scholar
- von Müller, F. T. A. H. (1982). Unterhaltungen mit Goethe [Conversations with Goethe]. Munich: Beck.Google Scholar