Olfactory identification in hemodialysis: acute and chronic effects on discrimination and response bias

The present experiment investigated the effects of renal failure and hemodialysis on olfactory identification and response bias assessed by a yes-no task administered both before and 1/2 hr after hemodialysis sessions. Identification and bias were measured under two theories. Results showed that dialysis patients had poorer identification ability overall than their controls which worsened after treatment. Patients' bias was more liberal than controls before treatment but became similar to the controls' afterwards; the bias measures Br and CL were differentially sensitive to diagnosis and time of testing effects. There was a dissociation between discrimination and bias changes in dialysis; patients' bias more closely resembled that seen in dementia (liberal) rather than depression (conservative).