Using objective measures to examine the effect of suspect-filler similarity on eyewitness identification performance.

When selecting fillers to include in a police lineup, one must consider the level of similarity between the suspect and potential fillers. In order to reduce misidentifications, an innocent suspect should not stand out. Therefore, it is important that the fillers share some degree of similarity. Importantly, increasing suspect-filler similarity too much will render the task too difficult reducing correct identifications of a guilty suspect. Determining how much similarity yields optimal identification performance is the focus of the proposed study. Extant research on lineup construction has provided somewhat mixed results. In part, this is likely due to the subjective nature of similarity, which forces researchers to define similarity in relative terms. In the current study, we manipulate suspect-filler similarity via a multidimensional scaling model constructed using objective facial measurements. In doing so, we test the "propitious heterogeneity" and the diagnostic-feature-detection hypotheses which predict an advantage of lineups with low-similarity fillers in terms of discriminability. We found that filler similarity did not affect discriminability. We discuss limitations and future directions.

Metamnemonic predictions of lineup identification.

After a crime is committed, investigators may query witnesses about whether they believe they will be to identify the perpetrator. However, we know little about how such metacognitive judgments are related to performance on a subsequent lineup identification task. The extant research has found the strength of this relationship to be small or nonexistent, which conflicts with the large body of literature indicating a moderate relationship between predictions and performance on memory tasks. In Studies 1-3, we induce variation in encoding quality by having participants watch a mock crime video with either low, medium, or high exposure quality, and then assess their future lineup performance. Calibration analysis revealed that assessments of future lineup performance were predictive of identification accuracy. This relationship was driven primarily by poor performance following low assessments. Studies 4 and 5 showed that these predictions are not based on a witness's evaluation of their encoding experience, nor on a contemporaneous assessment of memory strength. These results reinforce the argument that variation in memory quality is needed to obtain reliable relationships between predictions and performance. An unexpected finding is that witnesses who made a prediction shortly after encoding evinced superior memory compared to those who made a prediction later.

How does searching for faces among similar-looking distractors affect distractor memory?

Prior research has shown that searching for multiple targets in a visual search task enhances distractor memory in a subsequent recognition test. Three non-mutually exclusive accounts have been offered to explain this phenomenon. The mental comparison hypothesis states that searching for multiple targets requires participants to make more mental comparisons between the targets and the distractors, which enhances distractor memory. The attention allocation hypothesis states that participants allocate more attention to distractors because a multiple-target search cue leads them to expect a more difficult search. Finally, the partial match hypothesis states that searching for multiple targets increases the amount of featural overlap between targets and distractors, which necessitates greater attention in order to reject each distractor. In two experiments, we examined these hypotheses by manipulating visual working memory (VWM) load and target-distractor similarity of AI-generated faces in a visual search (i.e., RSVP) task. Distractor similarity was manipulated using a multidimensional scaling model constructed from facial landmarks and other metadata of each face. In both experiments, distractors from multiple-target searches were recognized better than distractors from single-target searches. Experiment 2 additionally revealed that increased target-distractor similarity during search improved distractor recognition memory, consistent with the partial match hypothesis.

Using objective measures to examine the effect of suspect-filler similarity on eyewitness identification performance.

When selecting fillers to include in a police lineup, one must consider the level of similarity between the suspect and potential fillers. In order to reduce misidentifications, an innocent suspect should not stand out. Therefore, it is important that the fillers share some degree of similarity. Importantly, increasing suspect-filler similarity too much will render the task too difficult reducing correct identifications of a guilty suspect. Determining how much similarity yields optimal identification performance is the focus of the proposed study. Extant research on lineup construction has provided somewhat mixed results. In part, this is likely because similarity is often defined in relative terms due to the subjective nature of similarity. In the current study, we propose an experiment in which we manipulate suspect-filler similarity via a multidimensional scaling model constructed using objective facial measurements. In doing so, we test the "propitious heterogeneity" and the diagnostic-feature-detection hypotheses which predict an advantage of lineups with low similarity fillers in terms of discriminability.

The role of metacognitive uncertainty in the delayed retrieval shift of older adults.

Strategic choice behavior of older adults in many skill acquisition tasks can be characterized as a delayed and/or incomplete shift to a more efficient retrieval-based strategy, even when older adults possess the requisite knowledge to use it successfully. The noun-pair lookup task (NPLT) requires verification of whether a centrally presented word pair matches one of a set of pairs displayed at the top of the screen. Because the pairings do not change, verification can be made from memory as the associations are learned. This study examines the role of metacognitive uncertainty in explaining older adults' delayed retrieval shift in the NPLT. Older and younger adults participated in a NPLT with previously learned items and new items. For each trial, the look-up table was shown only if the scanning strategy was selected. Some participants were given a precue informing whether the item had been previously learned. Retrieval strategy choice was low for older adults but precueing increased its frequency. Older adults' retrieval choices had minimal costs on NPLT accuracy, suggesting that the delayed retrieval shift can be exacerbated by metacognitive uncertainty that was reduced by precueing. The role of metacognitive uncertainty in older adults' retrieval avoidance was supported by a robust item-level regression effect of retrospective confidence judgments during prelearning tests and later NPLT retrieval strategy choices for older adults.

The role of retrieval during study: Evidence of reminding from self-paced study time.

The reminding effect (Tullis, Benjamin, & Ross, Journal of Experimental Psychology: General, 143[4], 1526-1540, 2014) describes the increase in recall of a studied word when a related word is presented later in the study list. However, because the process of reminding is thought to occur during study, measures of test performance are indirect indicators of the process of reminding and are subject to influences that arise during testing. The present research seeks evidence of reminding during encoding. In two experiments, self-paced study times were used to index the online process of reminding. In Experiment 1, pairs of repeated words, related words, and unrelated words were included in a study list. Study times were shorter for words related to prior words in the list, but only when the lag between those two words was short. Relatedness affected study time by inspiring a reduction in the threshold for termination of study for related words under massed conditions. Experiment 2 replicated the reduction in study time for related words and further showed that the study time allotted to an associate of an earlier item predicted better memory for that earlier word on a cued-recall test. In this experiment, an advantage in memory was observed for related words, and self-paced study time of one word during encoding was predictive of later memory for a related word. These results suggest a link between the action of reminding at study, as indexed by changes in the distribution of study time, and later benefits to remembering, as revealed by the reminding effect.

Memory for conversation and the development of common ground.

Efficient conversation is guided by the mutual knowledge, or common ground, that interlocutors form as a conversation progresses. Characterized from the perspective of commonly used measures of memory, efficient conversation should be closely associated with item memory-what was said-and context memory-who said what to whom. However, few studies have explicitly probed memory to evaluate what type of information is maintained following a communicative exchange. The current study examined how item and context memory relate to the development of common ground over the course of a conversation, and how these forms of memory vary as a function of one's role in a conversation as speaker or listener. The process of developing common ground was positively related to both item and context memory. In addition, content that was spoken was remembered better than content that was heard. Our findings illustrate how memory assessments can complement language measures by revealing the impact that basic conversational processes have on memory for what has been discussed. By taking this approach, we show that not only does the process of forming common ground facilitate communication in the present, but it also promotes an enduring record of that event, facilitating conversation into the future.