Observer Effects on Neuropsychological Performance: A Case Report

A woman with medically intractable epileptic seizures, mesial temporal sclerosis, developmental cognitive deficits, and dependent personality traits received the Portland Digit Recognition Test (PDRT) as part of a comprehensive neuropsychological battery. Portions of the PDRT were administered with her mother alternately present and absent in an A-B-A-B design. The patient performed significantly worse with her mother present than with her mother absent. The results suggest that situational variables sometimes have a potent effect on neuropsychological performance. The general practice of excluding significant others from the examining room during testing should be continued. The medicolegal implication of these data is that attorneys also should be excluded from the examination.