The role of eyebrows in face recognition

A fundamental challenge in face recognition lies in determining which facial characteristics are important in the identification of faces. Several studies have indicated the significance of certain facial features in this regard, particularly internal ones such as the eyes and mouth. Surprisingly, however, one rather prominent facial feature has received little attention in this domain: the eyebrows. Past work has examined the role of eyebrows in emotional expression and nonverbal communication, as well as in facial aesthetics and sexual dimorphism. However, it has not been made clear whether the eyebrows play an important role in the identification of faces. Here, we report experimental results which suggest that for face recognition the eyebrows may be at least as influential as the eyes. Specifically, we find that the absence of eyebrows in familiar faces leads to a very large and significant disruption in recognition performance. In fact, a significantly greater decrement in face recognition is observed in the absence of eyebrows than in the absence of eyes. These results may have important implications for our understanding of the mechanisms of face recognition in humans as well as for the development of artificial face-recognition systems.     

Is temporal spacing of tests helpful even when it inflates error rates?

The occurrence of errors is often thought to impede associative learning. This was tested in 2 studies, each of which involved 2 sessions. In Session 1, subjects learned foreign vocabulary (Experiment 1) or obscure English words (Experiment 2) and received 2 tests (each with corrective feedback) separated by a variable lag. Greater lags drastically reduced performance on the 2nd test. However, they dramatically improved performance in a Session-2 test given 1 day (Experiment 1) or 1 week later (Experiment 2). This pattern held even for items that elicited errors on the 1st test of Day 1. Evidently, the benefit of spacing overwhelms any possible harmful effect of producing errors. The results have clear and nonobvious implications for computer-aided instruction.     

Masked repetition and phonological priming within and across modalities

Lexical decision latencies to word targets presented either visually or auditorily were faster when directly preceded by a briefly presented (53-ms) pattern-masked visual prime that was the same word as the target (repetition primes), compared with different word primes. Primes that were pseudohomophones of target words did not significantly influence target processing compared with unrelated primes (Experiments 1-2) but did produce robust priming effects with slightly longer prime exposures (67 ms) in Experiment 3. Like repetition priming, these pseudohomophone priming effects did not interact with target modality. Experiments 4 and 5 replicated this general pattern of effects while introducing a different measure of prime visibility and an orthographic priming condition. Results are interpreted within the framework of a bimodal interactive activation model.     

Unique transitions between stimuli and responses in SRT tasks: Evidence for the primacy of response predictions

The present experiments aimed at separating the impact stimulus and response predictions have on serial learning and performance in SRT tasks. In Experiment 1, a unique transition between two of four responses in an otherwise random response sequence was triggered by ambiguous stimulus transitions, allowing local response predictions but no stimulus predictions. The data indicated explicit transition knowledge and strong performance benefits. In Experiments 2 and 3, unique transitions between two of four stimuli in otherwise random stimulus sequences allowed local stimulus predictions under conditions of ambiguous response transitions. The data indicated fragmentary explicit transition knowledge but no performance effects. Experiments 4a and 4b reveal that the inefficacy of the unique stimulus transitions in Experiments 2 and 3 was presumably due to the fact that the stimuli differed with respect to conjunctions of response relevant and response irrelevant features which participants did not have to attend. However, although in Experiments 4a and 4b unique transitions between response relevant stimuli were applied, substantial explicit transition knowledge but only marginal performance effects resulted. It is argued i) that in SRT tasks learning mechanisms are addressed that primarily strive for reliable predictions of forthcoming responses and ii) that for these mechanisms to work the predictors have to be attended. Response transitions are easily learned and used because both criteria are fulfilled. In contrast, pure stimulus transitions are learned only if the predictive stimuli are attended, and learned stimulus transitions become effective only to the extent that the predicted stimuli specify the required responses.     

Visual discrimination of number without counting

Observers in this study judged which of two fields contained the greater number of spots. Spots had difference-of-Gaussian luminance profiles and could differ in contrast polarity or were of uniform luminance and could differ in size. Weber fractions for all observers except one varied little except when spots varied in size. It is suggested that the results of this and previous studies might be explained by the existence of neurons tuned for number.     

The effects of different aperture-viewing conditions on the recognition of novel objects

The process of learning the structure of novel objects involves the selective use of information available in the distal stimulus. By allowing participants to explore the object within a limited field of view, we were able to examine more rigorously what regions of the object are actually selected in the learning process. Participants explored objects either by moving a circular aperture over a stationary novel object (the aperture-movement condition), or by moving the object behind a stationary aperture (the object-movement condition). Given the differences in how the spatial layout of object parts is revealed in the two study conditions, we expected that exploration would be more systematic in the aperture-movement condition than it would be in the object-movement condition, and would lead to better object recognition. We show evidence that in the aperture-movement condition exploration patterns were more related to the structure of the object and, as a consequence, the aperture-movement condition resulted in more accurate recognition in a later old--new discrimination test.     

Affective, behavioral, and cognitive functioning in adolescents with multiple suicide attempts

The purpose of this study was to examine affective, behavioral, and cognitive functioning in adolescents with multiple suicide attempts. Forty-seven adolescents with a history of multiple suicide attempts (MA) were compared to 74 single suicide attempters (SA) on psychiatric diagnosis, depressive symptoms, affect regulation, self-mutilation, alcohol use, and hopelessness. Results revealed that the MA group was more likely to be diagnosed with a mood disorder, and reported more severe depressive symptoms and anger, in comparison to the SA group. Behaviorally, the MA group had higher rates of disruptive behavior disorders and higher levels of affect dysregulation and serious self-mutilation than the SA group. Further, greater levels of hopelessness were reported by the MA than the SA group. After controlling for a mood disorder diagnosis, only differences in anger, affect dysregulation, and serious self-mutilation remained significant. Overall, results suggest that treatment with adolescent suicide attempters might specifically target anger and affect dysregulation to reduce risk for future suicidal behavior.     

Perspectives on probation and mandated mental health treatment in specialized and traditional probation departments

Despite the prevalence of mentally ill probationers, and probation officers' (POs') central role in their supervision, this is the first reported study to investigate how POs implement mandates to participate in psychiatric treatment. Five focus groups were conducted in major cities with 32 POs and 20 probationers representing a mix of traditional and "specialty" probation agencies. Three key findings resulted. First, there were considerable differences between POs in specialty and traditional agencies in the nature, range, and timing of strategies applied to monitor and enforce treatment compliance. Second, the quality of PO-probationer relationships colored POs' use of these strategies and was perceived as central to probationer outcomes. Relationships characterized by a respectful, personal, approach were perceived as more effective in achieving desired outcomes than those that were more authoritarian. Third, specialty agencies strongly emphasized offender rehabilitation whereas traditional agencies focused more exclusively on community safety. These agencies differed in how well probationers with mental illness "fit" their standard operating procedure. Implications for future research and directions for probation practice are discussed.     

Dogs (Canis familiaris) learn from their owners via observation in a manipulation task

Eighty-seven pet dogs (Canis familiaris) were involved in an experiment in which they had to solve a task to obtain a ball. After witnessing a full demonstration by their owner (10 times pushing the handle of the box, which released a ball), most dogs preferred to touch the handle sooner and more frequently in comparison with other parts of the box, and they used the handle to get the ball. In contrast, dogs in 3 control groups developed their own respective methods. The lack of emergence of the ball and playing after the demonstration did not affect the learning performance strongly. This suggests that in dogs the outcome of a demonstration plays only a restricted role in the manifestation of social learning.