Using Prosopagnosia to Test and Modify Visual Recognition Theory.

Biederman's contemporary theory of basic visual object recognition (Recognition-by-Components) is based on structural descriptions of objects and presumes 36 visual primitives (geons) people can discriminate, but there has been no empirical test of the actual use of these 36 geons to visually distinguish objects. In this study, we tested for the actual use of these geons in basic visual discrimination by comparing object discrimination performance patterns (when distinguishing varied stimuli) of an acquired prosopagnosia patient (LB) and healthy control participants. LB's prosopagnosia left her heavily reliant on structural descriptions or categorical object differences in visual discrimination tasks versus the control participants' additional ability to use face recognition or coordinate systems (Coordinate Relations Hypothesis).

Effect of Posttrial Visual Feedback and Fatigue During Drop Landings on Patellofemoral Joint Stress in Healthy Female Adults.

Patellofemoral pain (PFP) is common in females. Patellofemoral joint stress (PFJS) may be important in the development of PFP. Ground reaction force (GRF) during landing activities may impact PFJS.