Children's recall and source monitoring of a repeated event using a timeline as an interview aid

Investigators sometimes use timelines (visual depictions of time) to help children identify temporal information from experienced events or details from a particular instance of a repeated event. However, little is actually known about the efficacy of this visual aid on children's memories. Six‐ to 9‐year‐olds participated in four occurrences of a repeated event and were later interviewed with or without the use of a timeline. Children in the timeline condition were less accurate and made more source‐monitoring errors than those in the control condition. For items that appeared consistently throughout the events, a suggestibility effect was more evident for older children who used the timeline than those who did not. Overall, there was no clear evidence in support of the visual aid. Despite its popularity, our findings suggest that timelines should be further examined to establish whether, and under what circumstances, they might be used in investigative contexts.     

A computer system for processing eye-movement records

A computer system using the LINC-8 computer was developed to process eye-movement records from two 16-mm cine film input sources : the Mackworth stand camera and the Mackworth wide-angle camera. Data reduction was accomplished by projecting the films onto an X-Y plotting table. An operator marked, using a cursor, either the eyespot, in the case of the stand camera, or the pupil and display center, in the case of the wide-angle camera, in order to digitize the locus of the gaze. This information was normalized and stored on magnetic tape as: ordinal fixation number, fixation duration, and fixation coordinates (X and Y). A software library was created to analyze the three eye-movement measures. One program calculates interfixation distance, fixation time, and dispersion of fixations about a point. A second program operates on data matrices to: calculate area covered by a fixation pattern, frequency of redundant fixations in a fixation pattern, and distribution of fixations over features of the visual display. Data are displayed on either scope or the Calcomp plotter.     

Helping behaviour among people who use drugs: Altruism and mutual aid in a harm reduction program

People who use drugs, and particularly people experiencing addiction, are rarely afforded the opportunity to have their voices heard when it comes to drug treatment or drug policy or even when attempting to define themselves and their life experiences. Of course, there is much more to a person than one area of their behaviour. The current study seeks to capture and understand the lived experiences of people who use drugs, with a focus on their relationships and helping behaviour. We interviewed 32 participants in a harm reduction program seeking to provide understanding beyond stigmatizing and criminalizing drug narratives, by exploring their motivation and context for helping behaviours. Grounded theory methodology was used to understand the patterns of helping behaviour, along with the contexts in which help is or is not given. We particularly focus on participants' distribution of syringes and carrying medicine to reverse overdose (naloxone). Participants shared stories of altruism and mutual aid, along with barriers and disincentives to helping others. We situate these behaviours within contrasting environments of a free harm reduction program and the competitive market system of the U.S. society. Implications for practice and public policy are discussed.     

Activation of human motion processing areas during event perception

Observers are able to segment continuous everyday activity into meaningful parts. This ability may be related to processing low-level visual cues, such as changes in motion. To address this issue, the present study combined measurement of evoked responses to event boundaries with functional identification of the extrastriate motion complex (MT+) and the frontal eye field (FEF), two regions related to motion perception and eye movements. The results provided strong evidence that MT+ is activated by event boundaries: Individuals' MT+ regions showed strong responses to event boundaries, and MT+ was collocated with a lateral posterior region that responded at event boundaries. The evidence regarding the FEF was less conclusive: The FEF showed reliable but relatively reduced responses to event boundaries, but the FEF was medial and superior to a frontal area that responded at event boundaries. These results suggest that motion cues, and possibly eye movements, may play key roles in event structure perception.     

Individual differences in the selective processing of threatening information, and emotional responses to a stressful life event.

Previous research has established that high levels of trait anxiety commonly are associated with an automatic pattern of encoding selectivity, operating to favour the processing of emotionally threatening information. It has been suggested that this processing bias may play a functional role in mediating emotional vulnerability by moderating affective responses to stressful real life events. The current experiment employs a longitudinal design, capable of addressing the central predictions arising from this theoretical position. Thirty-one women awaiting colposcopy investigation were screened on both traditional questionnaire measures of emotional vulnerability, and on a modified emotional Stroop task that provided objective indices of their automatic and strategic patterns of processing selectivity. Subsequently, those 15 women who later received a diagnosis of cervical pathology reported the degree to which this diagnosis had impaired their level of emotional functioning. The results confirm that, at the initial test time, trait anxiety was indeed associated with an apparently automatic tendency to selectively process threat related distractor information. Furthermore, an index of this initial pattern of automatic processing selectivity was consistently the best predictor of the intensity of emotional distress elicited by the subsequent diagnosis of cervical pathology. None of our conventional questionnaire measures were capable of significantly predicting this later emotional response. We suggest that these findings offer empirical support for the hypotheses that patterns of automatic processing selectivity may moderate individuals' emotional responses to stressful life events.     

Adult age comparisons in the processing of event frequency information

The usual superiority in frequency-of-occurrence judgments of younger vs. older subjects was hypothesized to result from greater strategic encoding of the materials conveying frequency information. A subject-paced, visual search task was designed to control nontarget word encoding. Relative frequency judgments for the nontarget word pairs were equally accurate for younger and older subjects, and performance of both groups was above chance. Results suggest that strategic cover-task encoding can induce age differences in incidental frequency processing. Consistent with a nonoptimal as opposed to an optimal view, automatic processes require only minimal capacity for above-chance performance, but additional strategic resources can increase performance. When such additional resources are used more by younger than by older subjects, the former are better in frequency performance.     

Effects of time and event uncertainty upon sequential information processing

Two experiments were conducted to investigate the psychological refractory period (PRP), a delay induced into the second of two reaction times (RT) when the interstimulus interval (ISI) is short. In Experiment1, time and event uncertainty were factorially varied by providing or not providing S with foreknowledge of the ISI and the order in which the two events would occur, respectively. ISIs of0, 50, 100, 200, and400 msec were used. Time and event uncertainty produced independent degradation of both RTs. Also, the second RT (RT ₂ ) was delayed at50 msec ISI when both time and event certainty were present. Experiment 2 attempted to replicate this latter finding using ISIs of0, 25, 50, 75, and100 msec. Delays in RT ₂ were found for the middle three values of ISI. These results were interpreted as supporting a modified single channel theory of the PRP.     

PROJECT__X: A PL/1 program for processing acyclic digraphs

A PL/I program for constructing and processing acyclic digraphs is described. As an aid to exposition, an application of the program to the study of epistomological structure in human memory is discussed.     

Appletree: A multinomial processing tree modeling program for macintosh computers

Multinomial processing tree (MPT) models are statistical models that allow for the prediction of categorical frequency data by sets of unobservable (cognitive) states. In MPT models, the probability that an event belongs to a certain category is a sum of products of state probabilities. AppleTree is a computer program for Macintosh for testing user-defined MPT models. It can fit model parameters to empirical frequency data, provide confidence intervals for the parameters, generate tree graphs for the models, and perform identifiability checks. In this article, the algorithms used by AppleTree and the handling of the program are described.     

The implications of processing event sequences for theories of analogical reasoning

Sternberg (1977a, 1977b) has proposed a componential theory of information processing on analogies. The current study attempts convergent validation of the basic findings in verbal analogies by a method that is based on different underlying assumptions. Although the data were generally consistent with Sternberg’s theory, the data indicated thatapplication is better described by two separate events. Furthermore, the extent of individual differences in strategy models was so substantial that a higher level processing operation, such as control strategies, should be postulated, rather than to support a single-strategy model as characterizing Analogy solving.     

The relation between event processing and the duration of emotional experience

An emotional experience can last for only a couple of seconds up to several hours or even longer. In the present study, we examine to which extent covert intrapersonal actions (cognitions both related and unrelated to the emotion-eliciting stimulus) as well as overt interpersonal actions (social sharing) account for this variability in emotion duration. Participants were asked to report the duration of their anger, sadness, joy, and gratitude episodes on a daily basis during five days. Furthermore, information was collected with regard to their cognitions during the episodes and their social sharing behavior. Discrete-time survival analyses revealed that for three of the four emotions under study, stimulus-related cognitions with the same valence as the emotion lead to a prolongation of the episode; in contrast, both stimulus-related and stimulus-unrelated cognitions with a valence opposite to the emotion lead to a shortening. Finally, for the four emotions under study, social sharing was associated with a prolongation. The findings are discussed in terms of a possible process basis underlying the time dynamics of negative as well as positive emotions.     

Speech event related potentials reflect linguistic content and processing level

Amplitude changes in the auditory event related response reflect differences in linguistic content and the level of processing of spoken sentences. Thus, the neurophysiology of the cognitive processes underlying speech perception can be evaluated by noninvasive techniques. Semantically correct, semantically incorrect, and grammatically incorrect sentences were processed either semantically or syntactically by 25 subjects while their EEGs were recorded. The amplitude of the P250 component to each word varied with processing level. A slow positive wave appeared after semantically correct sentences regardless of the linguistic processing level. N480 and P780 components were observed following words which made the sentences incorrect.     

Cognition of the relation between an event and a circumstance understood to explain the event

A model is advanced for the process of explanation, according to which (a) an event to be explained is understood to be a value on a particular dimension of variation; (b) a circumstance believed to explain the event is understood to be a value on another dimension of variation; (c) the two dimensions are understood to be related such that the dimension whose value is to be explained is more likely to take that value when the dimension of circumstance takes its obtaining value than when the dimension of circumstance takes an alternative value. Evidence for the model is reported from a study in which Ss made two judgments about a human action-wchich of two statements of circumstance specifying alternative values for a certain dimension was the better explanation for the action, and which of the same two statements described the case in which the action, or for certain items the opposite action, was more likely to occur. For each of five different actions, the judgments were significantly related as required by the model.     

HMMTree: A computer program for latent-class hierarchical multinomial processing tree models

Latent-class hierarchical multinomial models are an important extension of the widely used family of multinomial processing tree models, in that they allow for testing the parameter homogeneity assumption and provide a framework for modeling parameter heterogeneity. In this article, the computer program HMMTree is introduced as a means of implementing latent-class hierarchical multinomial processing tree models. HMMTree computes parameter estimates, confidence intervals, and goodness-of-fit statistics for such models, as well as the Fisher information, expected category means and variances, and posterior probabilities for class membership. A brief guide to using the program is provided.     

multiTree: A computer program for the analysis of multinomial processing tree models

Multinomial processing tree (MPT) models are a family of stochastic models for psychology and related sciences that can be used to model observed categorical frequencies as a function of a sequence of latent states. For the analysis of such models, the present article presents a platform-independent computer program called multiTree, which simplifies the creation and the analysis of MPT models. This makes them more convenient to implement and analyze. Also, multiTree offers advanced modeling features. It provides estimates of the parameters and their variability, goodness-of-fit statistics, hypothesis testing, checks for identifiability, parametric and nonparametric bootstrapping, and power analyses. In this article, the algorithms underlying multiTree are given, and a user guide is provided. The multiTree program can be downloaded from http://psycho3.uni-mannheim.de/multitree.     

Relationship between rate of preparation for, and processing of, an event requiring a choice response

It is known that alcohol increases the time taken to identify signals and to make responses to them, but it is not known whether it also slows the rate of preparation for such events. These two performance parameters are not necessarily related, as age affects the former but not the latter. Twenty subjects participated in a 4-choice reaction time experiment in which they received no alcohol (NA) in the first session and either no alcohol (10 subjects) or 0.8 ml alcohol (A) per kg body weight (10 subjects) in the second session. In each session there were 300 practice trials, followed by 400 experimental trials at each one of five Response-Stimulus Intervals (RSI: 50, 100, 200, 400, and 800 msec). There was a significant effect of alcohol such that the reduction in response time from the first to the second session was 39 msec larger for the NA/NA group than for the NA/A group. Response time decreased significantly with increasing RSI, but there was no interaction between the effect of alcohol and RSI. Thus, alcohol slows the processing of an event requiring a choice response; however, like age and individual differences, but unlike practice, alcohol has no effect on the rate of preparation for that event. In addition, an analysis of what happened before and after an error revealed that practice and increasing RSI produce real improvements in performance rather than shifts in the tradeoff between speed and accuracy, whereas alcohol produces a real impairment. It is concluded that the relationship between the rate of preparation for, and processing of, a stimulus is not simple, as one factor (practice) influences both rates, whereas other factors (alcohol, individual differences, and age) influence the rate of processing only.     

Reaction to trauma: a cognitive processing model.

We integrated existing cognitive processing models of posttrauma reactions into a longitudinal model. Data were obtained after a multiple shooting in a city office block. The subject group comprised 158 office workers who were in the building at the time of the shootings. The methodology of this research was a repeated measures survey, with data collection at 4, 8, and 14 months posttrauma. Measures included the Impact of Events Scale (IES) and the Symptom Checklist-90-Revised. A path analysis was performed with the IES as an indication of cognitive processing. Intrusion and avoidance were shown to mediate between exposure to trauma and symptom development. Intrusion was also found to be negatively related to subsequent symptom levels. The findings provide provisional support for a cognitive processing model.     

Imageability and semantic association in the representation and processing of event verbs

This study examined the relative salience of imageability (the degree to which a word evokes mental imagery) versus semantic association (the density of semantic network in which a word is embedded) in the representation and processing of four types of event verbs: sensory, cognitive, speech, and motor verbs. ERP responses were recorded, while 34 university students performed on a lexical decision task. Analysis focused primarily on amplitude differences across verb conditions within the N400 time window where activities are considered representing meaning activation. Variation in N400 amplitude across four types of verbs was found significantly associated with the level of imageability, but not the level of semantic association. The findings suggest imageability as a more salient factor relative to semantic association in the processing of these verbs. The role of semantic association and the representation of speech verbs are also discussed.     

Repeated testing in eyewitness memory: a means to improve recall of a negative emotional event

Participants viewed either a violent, arousing film or a non-violent, control version of the same film. After viewing the film, they made three successive attempts to recall details of the event. Participants who were exposed to the negative emotional event were better than control participants at recalling details of the event itself, but they were worse at recalling details that preceded or followed the violence. Both groups of participants recalled significantly more information over successive recall attempts, suggesting that memory impairment due to arousal can be alleviated by repeated testing. Repeated testing was also associated with a small but reliable increase in memory intrusions. The implications of these findings for research on hypermnesia and on the relationship between arousal and memory are discussed. © 1998 John Wiley & Sons, Ltd.     

Children's false memories: easier to elicit for a negative than for a neutral event

The present study examined the role of valence in the development of children's implanted false memories. Seventy-six 7-year-old children listened to two true and one false narrative. The false narrative was either neutral ("moving to another classroom") or emotional negative ("being accused by the teacher for copying off your neighbor"). In addition, half of the children were presented with their class photograph while listening to the narratives. During two interviews, children recalled as many details as possible from the true and false events. Results showed that the negative event elicited more false memories than the neutral event. The presentation of a true photograph did not promote the development of false memories.