Elvira García-Bajos

Script knowledge modulates retrieval-induced forgetting for eyewitness events

To determine the influence of knowledge schemata on inhibitory processes we analysed how the typicality of the actions of an event modulated retrieval-induced forgetting (RIF). Participants were presented with a realistic videotape of a bank robbery. Based on a normative study, high- and low-typicality actions of the event were determined. After watching the video, participants practised retrieving either half of the high- or half of the low-typicality actions, and their performance was compared against a no-practice control group. Tests given immediately after the event and after a 1-week retention interval demonstrated significant RIF for low-typicality actions exclusively when low-typicality actions were practised, but a comparable forgetting effect did not emerge for highly schematic actions. These findings confirm that highly integrated script knowledge protects high-typicality actions of an event from inhibitory processes, and demonstrate that RIFs effects last far longer than has been previously found.

Recall, recognition, and confidence patterns in eyewitness testimony

The diversity of methods, contents and tests used in the study of eyewitness memory may have contributed to discrepancies in results in this field. In this experiment, using incidental or intentional learning, we examine the recall and recognition of actions and details concerning the central and peripheral information of a kidnapping. A similar pattern emerges in free recall, hits and recognition confidence: scores are much higher in actions than in central details and there are almost no differences between peripheral actions and details, showing that the distribution of attentional resources is different for actions and details in central than in peripheral information. Although in recall the degree of error was low, in recognition false alarms, especially those in central actions, reduced the level of accuracy to even lower than chance performance in both incidental and intentional groups, also showing that subjects accept false but plausible contents with a high level of confidence. Copyright

False memories for script actions in a mugging account

Why do subjects accept information that is typical but false? The present study analyses the effects of scripts on the creation of these false memories. Based on script information established in a normative data study, a brief narrative account of a mock mugging was elaborated with high- and low-typicality contents. Free recall turned out to be a synthesis of the event, centred more on typical actions than on low-typicality ones, and although there were few errors, they were actually script-consistent contents. In recognition the typicality of the sentences was systematically manipulated. There were more hits in high-typicality actions, but the accuracy rate was greater in low than in high-probability information due to the fact that the subjects accepted nearly half of the unstated typical actions. These false alarms received high confidence scores, showing that for the subjects these false memories represented real recollections. Furthermore, false memories, generated by activating our prior knowledge, were persistent after a weeks delay and resistant even to explicit instructions warning against such errors.

When stereotype knowledge prevents retrieval-induced forgetting

In the present study, we examined the effects of stereotypes and the typicality of traits in retrieval-induced forgetting (RIF). The participants in the experiment practiced half of the high-typicality, low-typicality or control traits associated with the name of a stereotype (athlete, scientist) or with the name of a person (Mikel, Jon). With the person name the high-typicality, low-typicality or control traits produced no evidence of stereotype activation. The traits were processed as independent features and generated RIF both immediately and at a one-week interval. Stereotype activation during encoding facilitated the integration of high-typicality traits, avoiding RIF in immediate and one-week recall. Moreover, both high-typicality and low-typicality traits benefited from stereotypes in one-week recognition. These findings show that previous knowledge contributes to integrate stereotypic traits that would otherwise compete for retrieval, thus producing RIF.

¡Esto es un atraco! Sesgos de la tipicidad en la memoria de testigos

Resumen En este estudio se analizan los efectos de la tipicidad en la memoria de testigos. Si las personas poseen conocimientos previos de los delitos típicos: guiones para las acciones y estereotipos sobre los atracadores, y los usan para comprender y recuperar un suceso, su memoria puede incluir también información típica, pero falsa. En un estudio normativo previo se determinaron las acciones implicadas en el atraco a un banco y las características de los atracadores y, después, se seleccionó una secuencia de un atraco a un banco. Conjugando los datos normativos y los contenidos del atraco, se elaboró una prueba de reconocimiento con acciones del suceso y características de los atracadores verdaderas y falsas, de tipicidad alta y baja. Se reconocieron mejor las acciones y las características de los atracadores de tipicidad alta que baja, pero al mismo tiempo los contenidos con tipicidad alta generaron una gran proporción de falsas alarmas. Así, los conocimientos previos parecen relevantes para el funcionamiento cognitivo, favorecen, pero también pueden sesgar la memoria de los testigos de un suceso.

The Power of Script Knowledge and Selective Retrieval in the Recall of Daily Activities

ABSTRACT In this study we examined the effects of script knowledge and selective retrieval on the recall of daily activities. The participants studied daily activities typically performed over the course of a normal day from morning to bedtime, presented in chronological order or as a random list. Then half of the participants practiced retrieval for part of the activities. The use of the script improved recall in the ordered presentation. The facilitation effect caused by retrieval practice was greater in the random presentation, showing that retrieval is a powerful mnemonic enhancer, especially for nonorganized materials. Script-driven processing in the ordered presentation prevented inhibitory effects derived from selective retrieval practice, whereas retrieval-induced forgetting was observed in the random presentation, which lacked the temporal and causal structure of the script. The results show the power of the script to moderate inhibition and the effectiveness of retrieval practice in the recall of daily activities.

Memory for Actions of an Event: Older and Younger Adults Compared

ABSTRACT Previous studies have shown increased false memory effects in older compared to younger adults. To investigate this phenomenon in event memory, in the present study, the authors presented younger and older adults with a robbery. A distinction was made between verbal and visual actions of the event, and recognition and subjective experience of retrieval (remember/know/guess judgments) were analyzed. Although there were no differences in hits, older adults accepted more false information as true and, consequently, showed less accurate recognition than younger adults. Moreover, older adults were more likely than younger adults to accompany these errors with remember judgments. Young adults accepted fewer false verbal actions than visual ones and awarded fewer remember judgments to their false alarms for verbal than for visual actions. Older adults, however, did not show this effect of type of information. These results suggest that aging is a relevant factor in memory for real-life eyewitness situations.

Differential Retrieval of Past and Future Autobiographical Experiences

Selective retrieval can both impair and enhance memory. In this study we analysed the effects of retrieval practice in the recall of past and future experiences. The participants generated past autobiographical experiences or imagined future experiences using recall cues of typical autobiographical experiences obtained in a previous study. The experiences were presented either in chronological or random order. Regardless of presentation order, retrieval practice produced facilitation in the free recall of practised past and future experiences. No retrieval-induced forgetting was observed for past experiences in the ordered presentation, showing that the temporal organisation of autobiographical experiences prevents the activation of inhibitory processes. Conversely, inhibition was significant in the free recall of future experiences presented in chronological order, possibly because future experiences present less welldefined temporal organisation, impairing the integration that suppresses inhibitory processes. Thus, retrieval-induced forgetting was evident in the random presentation of past and future autobiographical experiences.

Confianza y exactitud en la memoria de testigos vs. conocimientos generales

Resumen El objetivo de este estudio consiste en examinar si los sujetos son capaces de estimar la exactitud de sus respuestas en una prueba de reconocimiento V/F mediante valoraciones de la confianza. Se utilizaron tres tipos de materiales: conocimientos generales, un suceso y un texto expositivo. Además, la mitad de los sujetos recibieron dos tareas de práctica para que aprendieran a calibrar la confianza en función de la exactitud de sus respuestas, informándoles también de la naturaleza de los errores que pueden aparecer y de los sesgos en la confianza al valorar contenidos episódicos y semánticos. La práctica no afectó ni a la exactitud ni a la confianza. Respecto a los materiales, se produjeron dos patrones de respuesta: mientras los sujetos daban mayor confianza a sus respuestas correctas que erróneas, tanto para las frases verdaderas como falsas, en los conocimientos generales y en el texto, para el suceso aceptaron información falsa que no aparecía en el acontecimiento incluso con mayor confianza que sus rechazos correctos.

Falsas memorias en el recuerdo y reconocimiento de palabras

ResumenEn esta investigacion se estudian las falsas memorias en el recuerdo y reconocimiento de listas de palabras fuertemente asociadas a una palabra critica no presentada. Solo la mitad de los sujetos hicieron recuerdo tras la presentacion de cada lista, pero todos ellos respondieron posteriormente a una prueba de reconocimiento que incluia palabras presentadas, criticas y distractoras. Los sujetos recordaron las palabras criticas no presentadas en el 38% de los casos, las reconocieron en mas del 70% de la ocasiones y atribuyeron el origen de sus respuestas a la presencia de las palabras criticas en las listas. Casi todas las palabras criticas producidas en el recuerdo previo fueron posteriormente reconocidas, mientras que las no producidas solo se reconocieron en la mitad de las ocasiones. Se discuten las implicaciones de los resultados y se plantean diversas interpretaciones para el fenomeno de las falsas memorias.