Not looking yourself: The cost of self‐selecting photographs for identity verification

Photo‐identification is based on the premise that photographs are representative of facial appearance. However, previous studies show that ratings of likeness vary across different photographs of the same face, suggesting that some images capture identity better than others. Two experiments were designed to examine the relationship between likeness judgments and face matching accuracy. In Experiment 1, we compared unfamiliar face matching accuracy for self‐selected and other‐selected high‐likeness images. Surprisingly, images selected by previously unfamiliar viewers – after very limited exposure to a target face – were more accurately matched than self‐selected images chosen by the target identity themselves. Results also revealed extremely low inter‐rater agreement in ratings of likeness across participants, suggesting that perceptions of image resemblance are inherently unstable. In Experiment 2, we test whether the cost of self‐selection can be explained by this general disagreement in likeness judgments between individual raters. We find that averaging across rankings by multiple raters produces image selections that provide superior identification accuracy. However, benefit of other‐selection persisted for single raters, suggesting that inaccurate representations of self interfere with our ability to judge which images faithfully represent our current appearance.     

Behavioral pharmacology of the odor span task: Effects of flunitrazepam,ketamine, methamphetamine and methylphenidate

The Odor Span Task is an incrementing non‐matching‐to‐sample procedure that permits the study of behavior under the control of multiple stimuli. Rats are exposed to a series of odor stimuli and selection of new stimuli is reinforced. Successful performance thus requires remembering which stimuli have previously been presented during a given session. This procedure has been frequently used in neurobiological studies as a rodent model of working memory; however, only a few studies have examined the effects of drugs on performance in this task. The present experiments explored the behavioral pharmacology of a modified version of the Odor Span Task by determining the effects of stimulant drugs methylphenidate and methamphetamine, NMDA antagonist ketamine, and positive GABA_A modulator flunitrazepam. All four drugs produced dose‐dependent impairment of performances on the Odor Span Task, but for methylphenidate and methamphetamine, these occurred only at doses that had similar effects on performance of a simple odor discrimination. Generally, these disruptions were based on omission of responding at the effective doses. The effects of ketamine and flunitrazepam were more selective in some rats. That is, some rats tested under flunitrazepam and ketamine showed decreases in accuracy on the Odor Span Task at doses that did not affect simple discrimination performance. These selective effects indicate disruption of within‐session stimulus control. Overall, these findings support the potential of the Odor Span Task as a baseline for the behavioral pharmacological analysis of remembering.     

There are at least two kinds of probability matching: evidence from a secondary task

Probability matching is a suboptimal behavior that often plagues human decision-making in simple repeated choice tasks. Despite decades of research, recent studies cannot find agreement on what choice strategies lead to probability matching. We propose a solution, showing that two distinct local choice strategies—which make different demands on executive resources—both result in probability-matching behavior on a global level. By placing participants in a simple binary prediction task under dual- versus single-task conditions, we find that individuals with compromised executive resources are driven away from a one-trial-back strategy (utilized by participants with intact executive resources) and towards a strategy that integrates a longer window of past outcomes into the current prediction. Crucially, both groups of participants exhibited probability-matching behavior to the same extent at a global level of analysis. We suggest that these two forms of probability matching are byproducts of the operation of explicit versus implicit systems.     

Nodal structure and stimulus relatedness in equivalence classes: post-class formation preference tests

Three experiments used postclass formation within-class preference test performances to evaluate the effects of nodal distance on the relatedness of stimuli in equivalence classes. In Experiment 1, two 2-node four-member equivalence classes were established using the simultaneous protocol in which all of the baseline relations were trained together, after which all emergent relations probes were presented together. All training and testing was done using match-to-sample trials that contained two comparisons. After class formation, the effects of nodal distance were evaluated using within-class preference tests that contained samples and both comparisons from the same class. These tests yielded inconsistent performances for most participants. Experiment 2 replicated Experiment 1, but a third null comparison was used on all trials during class formation. Thereafter, virtually all of the within-class probes, for all participants, evoked performances that were consistent with the predicted effects of nodal distance, that is, the selection of comparisons that were nodally closer to the samples. It appears, then, that the establishment of the equivalence classes with a third null comparison induced control by nodal structure of the classes. Experiment 3 demonstrated the generality of these findings with larger classes that contained more nodal separations, that is, three-node five-member classes. Emergent-relations tests conducted immediately after the within-class tests showed the classes to be intact. Thus, the differential relatedness of stimuli in a class or their interchangeability depended on the content of a test trial: within-class probes occasioned responding indicative of differential strength among the stimuli in the class, while cross-class tests occasioned responding indicative of interchangeability of stimuli in the same class.     

Cross-domain analogies as relating derived relations among two separate relational networks

Contemporary behavior analytic research is making headway in analyzing analogy as the establishment of a relation of coordination among common types of trained or derived relations. Previous studies have been focused on within-domain analogy. The current study expands previous research by analyzing cross-domain analogy as relating relations among separate relational networks and by correlating participants' performance with a standard measure of analogical reasoning. In two experiments, adult participants first completed general intelligence and analogical reasoning tests. Subsequently, they were exposed to a computerized conditional discrimination training procedure designed to create two relational networks, each consisting of two 3-member equivalence classes. The critical test was a two-part analogical test in which participants had to relate combinatorial relations of coordination and distinction between the two relational networks. In Experiment 1, combinatorial relations for each network were individually tested prior to analogical testing, but in Experiment 2 they were not. Across both experiments, 65% of participants passed the analogical test on the first attempt. Moreover, results from the training procedure were strongly correlated with the standard measure of analogical reasoning.     

Reversing the Signaled Magnitude Effect in Delayed Matching to Sample: Delay-specific Remembering

Pigeons performed a delayed matching‐to‐sample task in which large or small reinforcers for correct remembering were signaled during the retention interval. Accuracy was low when small reinforcers were signaled, and high when large reinforcers were signaled (the signaled magnitude effect). When the reinforcer‐size cue was switched from small to large partway through the retention interval, accuracy accordingly changed from low to high. The opposite happened when the cue was switched from large to small. This dissociation of forgetting from the passage of time raises the possibility that remembering is delay‐specific. The reversal of the signaled magnitude effect during the retention interval is consistent with an attentional account in which the stimulus control of remembering is influenced by extraneous events.     

USING A BLOCKED-TRIALS PROCEDURE TO TEACH IDENTITY MATCHING TO A CHILD WITH AUTISM

Children with autism may struggle in developing conditional discrimination repertoires. Saunders and Spradlin (1989 , 1990 , 1993 ) arranged “blocked” teaching trials in which they presented the same sample stimulus repeatedly across trials (in lieu of randomly alternating targets across trials) and then faded the number of trials in each block. We replicated the effects of this blocked‐trials procedure in teaching identity matching to a child with autism and evaluated the necessity of fading. Arranging blocked trials facilitated the acquisition of identity matching, but fading the block size was not necessary to maintain discriminated performance.     

How a Group Goal May Reduce Social Matching in Group Performance: Shifts in Standards for Determining a Fair Contribution of Effort

Abstract

The authors investigated whether the presence of a specific group goal would reduce social matching (i.e., matching one's own performance to the performance expected from others) by serving as an alternative standard. As predicted, when there was no specific goal, the participants matched their own performance to the performance expected from other group members. When there was a specific group goal, the women no longer engaged in social matching, although that effect did not emerge among the men. Instead, the women's mean personal performance was close to the performance level representing an equal share of the group goal. Moreover, the participants' perceptions of a fair contribution mediated the performance of the men and the women, both in the presence and in the absence of a goal.