title: Tracing path-guided apparent motion in human primary visual cortex V1.
abstract: Vision is a constructive process. For example, a square, flashed at two distinct locations one after the other, appears to move smoothly between the two locations rather than as two separate flashes (apparent motion). Apparent motion is usually perceived along the shortest path between locations. Previous studies have shown that retinotopic activity in V1 correlates well with the subjective filling-in in apparent motion. If V1 activity truly reflects illusory motion, it should flexibly reflect filling-in of any path, subjectively perceived. Here, we used a path-guided apparent motion paradigm in which a faint cue, presented in addition to the squares, leads to a curved illusory motion path. We found retinotopic activity in V1 to reflect the illusory filling-in of the curved path, similarly to filling-in with linear, shortest paths. Moreover, our results show that activity along the linear path was less selective to stimulus conditions than the activity along the curved path. This finding may be interpreted as V1 activity representing a small subset of infinitely many possible solutions to ambiguous stimuli, whilst giving more weight to the shortest path/energy solution.
authors.affiliation: 1] Laboratory of Perceptual and Cognitive Dynamics, Center for Neuro-Engineering and Cognitive Science, Department of Electrical &Computer Engineering, University of Houston, USA [2] Laboratory of Psychophysics, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland.
authors.forename: Michel
authors.initials: M
authors.lastname: Akselrod
authors.affiliation: Laboratory of Psychophysics, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Herzog
authors.affiliation: Laboratory of Perceptual and Cognitive Dynamics, Center for Neuro-Engineering and Cognitive Science, Department of Electrical &Computer Engineering, University of Houston, USA.
authors.forename: Haluk
authors.initials: H
authors.lastname: Öğmen
mesh_terms: D000328:Adult; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007088:Illusions; D060306:Magnetometry; D008297:Male; D008875:Middle Aged; D009038:Motion; D010775:Photic Stimulation; D014793:Visual Cortex / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*