Alcohol, sexual arousal, and self-control

The effects of alcohol on self-regulation were investigated using delay of gratification for viewing time for an erotic film as the primary dependent measure. Other measures included reflection--impulsivity, locus of control, sexual-guilt scores, and continuous recording of subject's penile tumescence. Using a balanced placebo design, subjects were led to believe that they had consumed an alcoholic or a nonalcoholic beverage, and half of each of these two groups received either alcohol or tonic water. In addition, the effects of three doses of alcohol (placebo, low dose, high dose) were investigated. Instructional set, regardless of drink content, resulted in longer delay times and increased thoughts with sexual content. Although there was no significant relation between increasing dose of alcohol and delay time, there was an interaction between locus-of-control scores and alcohol dose. Externalizers showed an inverse linear relation between increasing dose of alcohol and delay time. Internalizers showed the opposite trend. Implications for the self-regulation of sexual behavior under the influence of alcohol are discussed.     

Discriminant validity of the MMPI for borderline personality disorder

This study explores the discriminant validity of the MMPI in relationship to the DSM-III and the Diagnostic Interview for Borderlines (DIB) constructs of Borderline Personality Disorder (BPD). A two-way analysis of variance model assessed differences between inpatients (n = 42) and outpatients (n = 42) and between BPD and nonBPD patients. We compare the best discriminant model for the current samples with previous BPD discriminant functions. The present study assesses a wider range of psychopathology in which the MMPI appears to be relatively insensitive to the BPD construct while retaining the high specificity reported in previous studies. Implications for the use of the MMPI as a diagnostic instrument are discussed.     

Does audiovisual speech offer a fountain of youth for old ears? An event-related brain potential study of age differences in audiovisual speech perception

The current study addressed the question whether audiovisual (AV) speech can improve speech perception in older and younger adults in a noisy environment. Event-related potentials (ERPs) were recorded to investigate age-related differences in the processes underlying AV speech perception. Participants performed an object categorization task in three conditions, namely auditory-only (A), visual-only (V), and AVspeech. Both age groups revealed an equivalent behavioral AVspeech benefit over unisensory trials. ERP analyses revealed an amplitude reduction of the auditory P1 and N1 on AVspeech trials relative to the summed unisensory (A + V) response in both age groups. These amplitude reductions are interpreted as an indication of multisensory efficiency as fewer neural resources were recruited to achieve better performance. Of interest, the observed P1 amplitude reduction was larger in older adults. Younger and older adults also showed an earlier auditory N1 in AVspeech relative to A and A + V trials, an effect that was again greater in the older adults. The degree of multisensory latency shift was predicted by basic auditory functioning (i.e., higher hearing thresholds were associated with larger latency shifts) in both age groups. Together, the results show that AV speech processing is not only intact in older adults, but that the facilitation of neural responses occurs earlier in and to a greater extent than in younger adults. Thus, older adults appear to benefit more from additional visual speech cues than younger adults, possibly to compensate for more impoverished unisensory inputs because of sensory aging.     

The GROOP effect: groups mimic group actions

Research on perception–action links has focused on an interpersonal level, demonstrating effects of observing individual actions on performance. The present study investigated perception–action matching at an inter-group level. Pairs of participants responded to hand movements that were performed by two individuals who used one hand each or they responded to hand movements performed by an individual who used both hands. Apart from the difference in the number of observed agents, the observed hand movements were identical. If co-actors form action plans that specify the actions to be performed jointly, then participants should have a stronger tendency to mimic group actions than individual actions. Confirming this prediction, the results showed larger mimicry effects when groups responded to group actions than when groups responded to otherwise identical individual actions. This suggests that representations of joint tasks modulate automatic perception–action links and facilitate mimicry at an inter-group level.     

Hand proximity—not arm posture—alters vision near the hands

Recent research has revealed remarkable changes in vision and cognition when participants place their hands near the stimuli that they are evaluating. In this paradigm, participants perform a task both with their hands on the sides of the monitor (near) and with their hands on their laps (far). However, that experimental setup has typically confounded hand position with body posture: When participants had their hands near the stimuli, they also always had their hands up around shoulder height. Thus, it is possible that the reported changes “near the hands” are instead artifacts of this posture. In the present study, participants performed a visual search task with their hands near and far from the stimuli. However, in the hands-near condition, participants rested their hands on a table, and in the hands-far condition, they had their arms raised. After eliminating the postural confound, we still found evidence for slower search rates near the hands—replicating earlier results and indicating that the hands’ proximity to the stimuli is truly what affects vision.     

Does effort influence inequity aversion in cotton-top tamarins (Saguinus oedipus)?

The human sense of fairness entails sensitivity not just to equality, the equal division of resources, but also to merit, the relationship between an individual’s share of resources and how hard they worked for their share. Recent evidence suggests that our sensitivity to equality has deep phylogenetic roots: several nonhuman animal species show an aversion to unequal reward distributions. However, the extent to which nonhuman animals share sensitivity to merit remains poorly understood, largely because previous studies have failed to properly manipulate work effort in inequity aversion tasks. Here, we tested whether cotton-top tamarins (Saguinus oedipus) would exhibit a differential response to inequity when acquiring rewards was either (1) effortful or (2) effortless. Subjects engaged in a pulling task in which they had an opportunity to deliver a disadvantageously unequal distribution of food to themselves and a partner (one piece for self, four pieces for partner). We made delivery effortful by adding a weight to the pulling handle. Critically, effort was calibrated to each individual. Results show that individuals varied markedly in their response to effort, highlighting the importance of manipulating work effort at the individual level. Overall, subjects showed little aversion to inequity. However, subjects were slightly less likely to accept inequity when doing so was effortful, although this effect was pronounced in only one individual. Our findings suggest a new method for capturing individual variation in effort and for studying the roots of the concept of merit in nonhuman animals.     

Using movement and intentions to understand human activity

During perception, people segment continuous activity into discrete events. They do so in part by monitoring changes in features of an ongoing activity. Characterizing these features is important for theories of event perception and may be helpful for designing information systems. The three experiments reported here asked whether the body movements of an actor predict when viewers will perceive event boundaries. Body movements were recorded using a magnetic motion tracking system and compared with viewers’ segmentation of his activity into events. Changes in movement features were strongly associated with segmentation. This was more true for fine-grained than for coarse-grained boundaries, and was strengthened when the stimulus displays were reduced from live-action movies to simplified animations. These results suggest that movement variables play an important role in the process of segmenting activity into meaningful events, and that the influence of movement on segmentation depends on the availability of other information sources.     

The onset of receding motion captures attention: comment on Franconeri and Simons (2003)

Franconeri & Simons (2003) reported that some but not all types of motion capture attention in a visual search task, ostensibly because some types of motion are behaviorally significant. In the present article, we argue that a more parsimonious explanation of their results is that the onset of motion, but not motion per se, captures attention. This conclusion helps to resolve inconsistencies between the Franconeri and Simons findings and earlier reports from other investigators and is consistent with results that we have recently reported (Abrams & Christ, 2003). The Franconeri and Simons interpretation rests largely on their failure to find attentional capture by one type of motion-simulated receding motion. We report here the results of two experiments that demonstrate that the onset of receding motion does indeed capture attention when the motion is produced using stereo depth cues. As we have argued elsewhere, the capture of attention in displays containing motion appears to be dependent on the onset of the motion, rather than on the mere presence of specific types of motion as suggested by Franconeri and Simons. One possible explanation is that the onset of motion captures attention because it serves as a strong cue to animacy--and the detection of nearby animals can have important consequences for survival.