Inferotemporal neurons represent low-dimensional configurations of parameterized shapes.
Behavioral studies with parameterized shapes have shown that the similarities among these complex stimuli can be represented using a low number of dimensions. Using psychophysical measurements and single-cell recordings in macaque inferotemporal (IT) cortex, we found an agreement between low-dimensional parametric configurations of shapes and the representation of shape similarity at the behavioral and neuronal level. The shape configurations, computed from both the perceived and neuron-based similarities, revealed a low number of dimensions and contained the same stimulus order as the parametric configurations. However, at a metric level, the behavioral and neural representations deviated consistently from the parametric configurations. These findings suggest an ordinally faithful but metrically biased representation of shape similarity in IT.
Op de Beeck
H
H
Laboratorium voor Neuro- en Psychofysiologie, K.U. Leuven, Campus Gasthuisberg, Herestraat 49, B-3000 Leuven, Belgium.
Wagemans
J
J
Vogels
R
R
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D004193:Discrimination Learning / Q000502:physiology; D006801:Humans; D008253:Macaca mulatta; D009474:Neurons / Q000502:physiology*; D015588:Observer Variation; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation; D011597:Psychomotor Performance / Q000502:physiology; D013028:Space Perception / Q000502:physiology; D013702:Temporal Lobe / Q000166:cytology / Q000502:physiology*; D014793:Visual Cortex / Q000166:cytology / Q000502:physiology*; D014795:Visual Pathways / Q000166:cytology / Q000502:physiology*