Areal differences in depth cue integration between monkey and human
Fig 8
We assessed whether monkeys were able to discriminate different depth levels using the four stimulus conditions of the main experiment. (A) We show sensitivities for depth differences between two sequentially presented planes for monkeys B and T. Both monkeys were able to discriminate between depths for all conditions when the reference and target planes differed by more than 1.8 arcmin in depth. Particularly, monkey B performed excellently and was able to classify between congruent stimuli even for the finest depth difference used (0.3 arcmin). In general, when depths were discriminable, monkeys showed highest sensitivity to the congruent stimulus and lower sensitivity for motion than disparity. Discrimination for the incongruent condition was comparable to that of the single cues. (B) Overall discrimination accuracy across depth levels and monkeys. (C) Sensitivity calculated based on j.n.d. thresholds. As in humans, monkeys were most sensitive when disparity and motion concurrently signalled depth differences, and they were least sensitive for relative motion–related differences. Error bars show bootstrapped 95% confidence intervals; significance was set to P < 0.01. The underlying data for the figures can be found at https://doi.org/10.5061/dryad.6pm117m. j.n.d., just noticeable difference.