Figure 2: Measures of photoreceptor noise for estimation of the feature detectability threshold.
From: Visual acuity of the honey bee retina and the limits for feature detection
(Left) Single and averaged (±σ) raw response of a frontal photoreceptor (azimuth, 27°; elevation, −16°) when a near-threshold dark object (0.6° × 0.6°) was swept across its receptive field (v = 65°/s). The black bar below the averaged responses denotes the approximate receptive field of the cell (defined here by its acceptance angle, Δρ) transformed into the time domain. (Right) In order to quantify the contribution of extracellular/instrument noise estimates, noise threshold was calculated as standard deviation of the intracellular responses to a blank screen corrected for the responses to the same stimulus obtained right outside the cell.
