Changes in the incidental context impacts search but not loading of the motor buffer

During a retention test, a change in the nature of the incidental contextual information present during training can have a deleterious impact on response selection by not activating particular subsets of information in memory that help direct the retrieval process. The present experiment addressed whether a change in the incidental context also impacted the completion of processes associated with loading and searching the motor buffer during motor programming. A self-select paradigm was used to describe the planning and execution of one- and four-element sequences that consisted of short and long duration key-presses. During a test phase following training, changes in the incidental contextual information impeded the search of the motor buffer. However, loading specific timing information into the motor buffer was unaffected by shifts in contexts. These data support the contention that contextual information plays a fundamental role in a broad array of movement-planning operations that involve search and retrieval type activity.     

“All I remember is the black eye”: A distinctive facial feature harms eyewitness identification

Many crimes occur in which a perpetrator has a distinctive facial feature, such as a tattoo or black eye, but few eyewitness identification (ID) studies have involved such a feature. We conducted an experiment to determine how eyewitness ID performance is impacted by a distinctive facial feature, and how police could deal with this issue. Participants (N = 4,218) studied a target face with or without a black eye, and later viewed a simultaneous photo lineup either containing the target or not. For those who saw a target with a black eye, this feature was either replicated among all lineup members or was removed. The black eye harmed empirical discriminability regardless of replication or removal, which did not differ. However, participants responded more conservatively when the black eye was removed, compared to replication. Lastly, immediate confidence was consistently indicative of accuracy.     

A computational approach to modeling population differences

Four experiments were conducted to determine whether the Hyperspace Analogue to Language (HAL) model of semantic memory could differentiate between two different populations. An analysis of the differences in densities (or average distances between word neighbors in semantic space) in HAL matrices—generated from text corpora derived from younger and older adults—confirmed that HAL was able to distinguish between the two age groups. This difference was again detected when structured interview data were used to build the corpora. A third experiment, designed to test the specificity of HAL in detecting differences between groups, did not detect any difference in the densities of the memory representations when older adults generated both the test corpora. The final experiment, conducted on the language of adults with Alzheimer’s and normal adults, again demonstrated that HAL could discriminate between the two populations. These results suggest that HAL is capable of modeling, on the basis of changes in mean density, some of the differences between populations without modifying the model itself but, rather, by changing the text corpus from which the model creates its representations in semantic space.     

Weapons and Eye Contact as Instigators or Inhibitors of Aggressive Arousal in Police-Citizen Interaction1

A field experiment was conducted with police officers during the normal course of their traffic patrol duties. The purpose was to determine whether the presence of holstered weapons and mirror sunglasses affected the degree of aggressiveness expressed nonverbally, and reported on a mood scale by citizens halted for an information check (neutral condition) or in order to be given a traffic ticket (negative condition). Results indicated that subjects in the negative condition both expressed and reported more aggressivity when the police officer wore a weapon than when no weapon was visible. The use of sunglasses had no effect on aggressivity but resulted in the officer's being perceived more negatively, though he was not perceived more negatively when he wore a weapon. No sex differences in expressed or reported aggressivity were obtained, although some sex differences on measures of secondary interest did occur. The implications of these findings for research on the “weapons effect” and on policy regarding the visibility of police weapons and the wearing of sunglasses by police officers are discussed.     

Readability of prescription drug labels by older and younger adults

This experiment investigated the readability of medication labels using various combinations of fonts, sizes, and weights of print. Older and younger adult reading speeds and error rates for different print types were compared for both bottle and flat labels. Findings of the study indicated significant differences in reading speed, error rates, and subjective evaluations for print characteristics investigated. Furthermore, the effects of these print characteristics varied for different age groups. Implications of these findings for the design of medication labels for older adults are discussed.     

Racial differences in birth outcomes: the role of general, pregnancy, and racism stress.

OBJECTIVE: This study examined the role of psychosocial stress in racial differences in birth outcomes. DESIGN: Maternal health, sociodemographic factors, and 3 forms of stress (general stress, pregnancy stress, and perceived racism) were assessed prospectively in a sample of 51 African American and 73 non-Hispanic White pregnant women. MAIN OUTCOME MEASURES: The outcomes of interest were birth weight and gestational age at delivery. Only predictive models of birth weight were tested as the groups did not differ significantly in gestational age. RESULTS: Perceived racism and indicators of general stress were correlated with birth weight and tested in regression analyses. In the sample as a whole, lifetime and childhood indicators of perceived racism predicted birth weight and attenuated racial differences, independent of medical and sociodemographic control variables. Models within each race group showed that perceived racism was a significant predictor of birth weight in African Americans, but not in non-Hispanic Whites. CONCLUSIONS: These findings provide further evidence that racism may play an important role in birth outcome disparities, and they are among the first to indicate the significance of psychosocial factors that occur early in the life course for these specific health outcomes.     

A method for increasing empirical discriminability and eliminating top‐row preference in photo arrays

It is important to consider the two parameters of signal detection theory, discriminability and response bias, when evaluating eyewitness identification from simultaneous lineups. On the basis of the diagnostic feature‐detection hypothesis, we tested a method for increasing discriminability that encourages eyewitnesses to carefully rank each lineup member based on match to their memory for a perpetrator. This procedure increased empirical discriminability and also eliminated a response bias that is largely overlooked in the literature: Participants were biased to choose from the top row of the six‐pack (2 × 3) lineup commonly used in the United States. We argue that suspect position in the simultaneous lineup is an important variable to consider for researchers and the criminal justice system. We also encourage researchers to test the ranking procedure to determine if such a simple set of instructions could be utilized by police to help eyewitnesses correctly sort innocent versus guilty suspects.     

Theoretical and methodological implications of language experience and vocabulary skill: priming of strongly and weakly associated words

The effect of second language experience and vocabulary ability was investigated in a semantic priming experiment with weakly related English word pairs (e.g., city-grass). Participants made lexical decisions to targets preceded by unrelated or weakly related primes or to nonword targets preceded by words. Reliable priming was found for monolingual participants; participants who had acquired a second language showed either marginal or nonreliable effects. A similar pattern of results was found with the analysis of vocabulary ability. Only participants with the greater vocabulary ability showed a priming effect. Although previous research has shown that participants with a broad range of linguistic backgrounds demonstrate the typical semantic priming effect (e.g., green-grass) with strongly associated word pairs, weaker relationships seem to require an extensive contextual history for retrieval.