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Full-Text Articles in Medicine and Health Sciences
Initial Findings On Visual Acuity Thresholds In An African Elephant (Loxodonta Africana), Melissa R. Shyan-Norwalt, Jeff Peterson, Barbara Milankow King, Timothy E. Staggs, Robert H.I. Dale
Initial Findings On Visual Acuity Thresholds In An African Elephant (Loxodonta Africana), Melissa R. Shyan-Norwalt, Jeff Peterson, Barbara Milankow King, Timothy E. Staggs, Robert H.I. Dale
Scholarship and Professional Work - LAS
There are only a few published examinations of elephant visual acuity. All involved Asian elephants (Elephas maximus) and found visual acuity to be between 8′ and 11′ of arc for a stimulus near the tip of the trunk, equivalent to a 0.50 cm gap, at a distance of about 2 m from the eyes. We predicted that African elephants (Loxodonta africana) would have similarly high visual acuity, necessary to facilitate eye-trunk coordination for feeding, drinking and social interactions. When tested on a discrimination task using Landolt-C stimuli, one African elephant cow demonstrated a visual acuity of …
Lifting Without Seeing: The Role Of Vision In Perceiving And Acting Upon The Size‐Weight Illusion, Gavin Buckingham, Melvyn A. Goodale
Lifting Without Seeing: The Role Of Vision In Perceiving And Acting Upon The Size‐Weight Illusion, Gavin Buckingham, Melvyn A. Goodale
Psychology Presentations
Our expectations of an object’s heaviness not only drive our fingertip forces, but also our perception of heaviness. This effect is highlighted by the classic size-weight illusion (SWI), where different‐sized objects of identical mass feel different weights (Charpentier, 1891) long after any initial errors in the application of fingertip forces have been corrected (Flanagan & Beltzner, 2000).
Here, we examined whether our expectations about the weight of an upcoming lift are sufficient to induce the SWI in a single wooden cube when lifted without visual feedback, by varying the size of the object seen prior to the lift during a …