A comparison study of eyewitness, verbal earwitness, and nonverbal earwitness memory.

Abstract

Over the past 20 years, the body of literature on eyewitness identification has increased to such a degree that its application to the courtroom meets with only minimal resistance from the field of psychology. However, the research on verbal earwitness identification or voice identification is much less exhaustive. There is even less empirical evidence regarding nonverbal earwitness identification. For example, do witnesses process shots fired from a gun, the screeching of tires, or the slamming of in the same manner they process faces or voices? This lack of valid and sound research appears to be a serious deftcit in the literature. This study was designed to examine whether some of the same assumptions that hold true for eyewitness and verbal earwitness also hold true for nonverbal earwitness. Data was gathered from 120 undergraduates in 6 introductory psychology classes at a small midwestern university. A questionnaire consisting of 20 items, along with a corresponding Likert type scale for measuring confidence, and a short demographic sheet were used in data collection. Four aspects of eyewitness and earwitness identification were examined: confidence, delay interval, gender, and age. In order to explore the results 2 (gender) x 3 (delay) x 5 (question type) repeated measures analysis of variance were performed on the dependent variables of accuracy and confidence. The main effects of delay and question type were found to be significant for both accuracy and confidence. The interaction of delay x question type was significant for subject accuracy. Significant correlations were also uncovered between confidence and three of the five question types (visual, verbal auditory, verbal auditory-visual). A significant correlation resulted when examining age and the verbal auditory question. The results indicate that s1m1lar assumptions can be made in regard to many as Pects of eyewitness, verbal earwitness, and nonverbal earwitness stimuli. However, the results also indicate that nonverbal earwitness stimuli also exhibit unique characteristics, separate from eyewitness or verbal earwitness stimuli. The legal implications for these findings and directions for possible future research are also discussed.