Stimulus and response repetition effects in the detection of sounds: evidence of obligatory retrieval and use of a prior event

Three experiments were performed to examine the extent to which the time required to detect a probe sound is determined by the acoustic characteristics of a preceding prime sound and by the nature of the response made to the prime. The results of Experiment 1 revealed that the effect of frequency repetition was facilitative when a response was made to the occurrence of both the prime and the probe, but was inhibitory when a response was made only to the probe. In contrast, there was no significant effect of location repetition when responses were made to both prime and probe but there was a strongly inhibitory effect when a response was required only to the probe. These results suggest that the acoustic characteristics of the prime along with information about any response made to it, are used in preparing and executing a response to the probe. Experiment 2 was designed to disrupt the temporal link between prime and probe as a way to discourage such retrieval. The results of the experiment revealed that although a response was required to both the prime and probe, no significant effect of frequency repetition was apparent but a robust inhibitory effect of location repetition emerged. In the third experiment repetition effects both within a trial (i.e., prime to probe) and between trials (i.e., probe to prime) were examined. A facilitative effect of frequency repetition was apparent when the interval between sounds was brief, and an inhibitory effect of location repetition was apparent when the interval between sounds was relatively lengthy. Taken together these results suggest that even simple perceptual judgments may be influenced by retrieval of information about a previous processing episode and that effects of frequency repetition and location repetition may be mediated by different mechanisms.     

Anchoring effects on performance judgments

Three studies were conducted investigating the effects of irrelevant anchors on performance judgments. Both a lab and field study demonstrated that an alternative anchoring manipulation that did not involve an explicit comparative question had effects on performance judgments similar to a traditional anchoring manipulation. The final study examined whether the anchoring effects were more likely when the anchor was highly applicable to the final judgment. The results indicated that both highly applicable and low applicable anchors produced an anchoring effect, but the highly applicable anchors had a larger effect on performance judgments. Evidence was also found for asymmetrical anchoring effects. In two of the three studies, high anchors increased performance judgments relative to the control group, whereas low anchors were not significantly different from the control group.     

The Effects of a Diversity Learning Experience on Positive and Negative Diversity Perceptions

Using a pretest-posttest research paradigm, we administered the Reaction-To-Diversity Inventory to students enrolled in a workplace diversity course at a regional Midwestern university. Our results show that the diversity experience produced an increase in the number of positive and negative perceptions students associated with workplace diversity. Gender also played a significant role in determining diversity perceptions. We discuss the implications of our findings for the design, implementation, and evaluation of diversity learning experiences in academic and corporate settings.     

Emergent Processes in Group Behavior

ABSTRACT— Just as neurons interconnect in networks that create structured thoughts beyond the ken of any individual neuron, so people spontaneously organize themselves into groups to create emergent organizations that no individual may intend, comprehend, or even perceive. Recent technological advances have provided us with unprecedented opportunities for conducting controlled laboratory experiments on human collective behavior. We describe two experimental paradigms in which we attempt to build predictive bridges between the beliefs, goals, and cognitive capacities of individuals and patterns of behavior at the group level, showing how the members of a group dynamically allocate themselves to resources and how innovations diffuse through a social network. Agent-based computational models have provided useful explanatory and predictive accounts. Together, the models and experiments point to tradeoffs between exploration and exploitation—that is, compromises between individuals using their own innovations and using innovations obtained from their peers—and the emergence of group-level organizations such as population waves, bandwagon effects, and spontaneous specialization.     

Statistical Power Analysis in Psychological Research

Reviews of the psychological literature suggest that many studies lack sufficient statistical power to detect effects of interest. Increased attention to statistical power by journal editors, reviewers, and funding agencies has led to a need for researchers to consider power carefully when designing studies. Our goal is to present an overview of issues that influence statistical power in the context of traditional research designs and analytic methods. We then extend the discussion of statistical power to complex designs and analyses providing readers with sources useful for evaluating power in the design stage of conducting research. Finally, we advocate the use of simulation and Monte Carlo methods as a flexible general strategy for designing research studies with adequate statistical power.     

Proximal Norms,Selected Sociodemographics,and Drinking Behavior Among University Student Athletes

Few studies have examined social norm theory with subpopulations of college students. In this study, the authors examined the relationships between social norms and student‐athlete drinking. Results suggest drinking is a function of proximal norms, particularly related to teammates. Implications for counselor interventions are discussed.     

The role of valence and frequency in the emotional Stroop task

People are generally slower to name the color of emotion-laden words than they are to name that of emotionally neutral words. However, an analysis of this emotional Stroop effect (Larsen, Mercer, & Balota, 2006) indicates that the emotion-laden words used are sometimes longer, have lower frequencies, and have smaller orthographic neighborhoods than the emotionally neutral words. This difference in word characteristics raises the possibility that the emotional Stroop effect is partly caused by lexical rather than by emotional aspects of the stimuli-a conclusion supported by the finding that reaction times to name the color of low-frequency words are longer than those for high-frequency words (Burt, 2002). To examine the relative contributions of valence and frequency in color naming, we had 64 participants complete an experiment in which each of these variables was manipulated in a 3 x 2 factorial design; length, orthographic neighborhood density, and arousal were balanced. The data indicate that valence and word frequency interact in contributing to the emotional Stroop effect.     

The role of local context in autoshaping

Three experiments used an autoshaping procedure with pigeons to examine the effects of nonreinforced, nontarget stimuli (ITI-fillers) during the intertrial interval on responding to a reinforced target CS. Experiment 1 replicated a previous demonstration that an ITI-filler that occupied a substantial portion of the ITI attenuated responding to the target CS relative to a group trained with a similar ITI but lacking the ITI-filler. Experiment 2 found that the superiority of responding typically found with a long ITI relative to a short ITI, that is, the trial-spacing effect, can be reversed by imposing a filler stimulus during the ITI in the former condition. Experiment 3, using a within-subject design, found that when one background stimulus condition occupied a majority of the interreinforcement interval, pairings of one target CS with reinforcement that were embedded within this background condition, that is, a long duration local context occurred for this CS, yielded better performance that a second, reinforced, target CS paired with reinforcement in the shorter duration background condition. These results confirmed predictions derived from a local context view of cycle time. Comparator theories of classical conditioning require incorporation of this notion into their conceptualization of effective cycle time in order to explain the present findings.