Face recall: An examination of some factors limiting composite production accuracy.

Abstract

Contemporary face composite systems require scrutiny of many alternative features during the construction phase and judgments of similarity based on viewing features divorced from a facial context. The role of these two factors in limiting composite production accuracy was assessed in three linked experiments. In Experiment 1, 60 students observed a target face and made similarity judgments on sample eyes or mouths drawn from a Photo-fit Kit before attempting to identify the same features of the target. Experiment 2 was a replication, except that the interpolated judgments were made on the features in the context of a complete Photo-fit face resembling the target. In neither experiment did the Photo-fit components significantly interfere with recognition of the corresponding features of the target. In Experiment 3, the similarity ratings from memory provided by subjects in the previous experiments were compared with parallel sets of ratings furnished by 30 students in the presence of the target. Mean judgments of similarity made from memory on isolated features were discrepant from all other ratings. These results were interpreted as suggesting that, whereas interference is not a major problem, judging resemblance from features seen in isolation may be a serious source of distortion in composite production.Experimental studies of face recall systems developed for police work, like Identikit and Photo-fit, 1 generally show low levels of accuracy and an insensitivity to variables that normally influence recall performance

Holistic face processing can inhibit recognition of forensic facial composites.

“…The composite systems require witnesses to select features, or judge likeness within the context of whole faces (e.g. Davies & Christie, 1982;Tanaka & Sengco, 1997). It would be useful to determine whether holistic face processing is beneficial, or whether features should be selected before generating the composite likeness.…”

Whole-face procedures for recovering facial images from memory

“…Each technique involves an overall or holistic procedure, which is why recognition-itself a holistic process (e.g. Davies & Christie, 1982;Tanaka & Farah, 1993)-increased with each one. The techniques are likely to enhance recognition in different ways.…”

Aplicación de la psicología al estudio de los procedimientos policiales de recuerdo de personas

“…Otras variables estudiadas son: la posible interferencia al ver distintas formas de las mismas características faciales (por ejemplo, 20 tipos de ojos) y tener que escoger sólo una, que parece no afectar significativamente a la imagen final (Davies y Christie, 1982); el modo de presentación, por medio de fotos o de dibujos, donde parece que ciertas rayas de los retratos-robot disminuyen la calidad de la imagen final, y los retoques son imprescindibles (Davies, 1982); la representatividad de las características faciales con que cuenta el sistema, donde el Photofit aventaja a los otros sistemas (Davies, 1982); la importancia de la restauración del contexto en que ocurrió el suceso durante el interrogatorio en la comisaría, para guiar la memoria del testigo y mejorar, así, la calidad de su recuerdo (Davies y Milne, 1985); el tener presente estudios anteriores que llaman la atención sobre la posibilidad de presiones, sobre los testigos, para que se produzca una respuesta, para poder llevar adelante el trabajo policial (Buckhout, 1974); y la posibilidad, íntimamente unida a la anterior, de que una vez formada la imagen del sospechoso -y aunque no sea la correcta-el testigo se autoconvenza de la autenticidad de su recuerdo y malogre el trabajo policial (Loftus, 1976;Mauldin y Laughery, 1981).…”

“…Con respé'cto a la construcción de los sistemas de retrato-robot, una importantísima limitación es, precisamente, que estos sistemas entienden que la cara de una persona debe componerse sumándose las diferentes características faciales aisladas, no interpretándose como un todo (Davies y Christie, 1982). Sin embargo, parece que la percepción y la memoria humanas se adecúan mejor a una interpretación global del todo (Christie y Ellis, 1981;Clifford y Bull, 1978).…”