The measurement of response force during a lever-press shock-escape procedure in rats

Three albino rats were given extensive exposure to an escape procedure in which shocks were scheduled to occur 30 sec apart. The amount of downward force exerted on the lever was continuously recorded and compared with traditional discrete measurement in which only responses above an arbitrary force threshold were recorded. Subjects typically remained in contact with the lever throughout the shock-free intertrial interval. Shock onset reliably occasioned a brief lurch from and return to the lever, which resulted in a lever-press escape response being recorded. Lever contact, which occupied an average of 90% of session time, showed great stability in force after a brief (e.g., 5-sec) period of instability after each shock terminated. In general, continuous measurement revealed considerably different results than discrete measurements of on-lever behavior. For example, continuous lever contact fluctuating near response threshold was often recorded as discrete responding, and sustained lever contact occurring below response threshold was omitted from discrete measurement.     

Perceptual priming is not a necessary consequence of semantic classification of pictures

Four experiments investigated how repetition priming of object recognition is affected by the task performed in the prime and test phases. In Experiment 1 object recognition was tested using both vocal naming and two different semantic decision tasks (whether or not objects were manufactured, and whether or not they would be found inside the house). Some aspects of the data were inconsistent with contemporary models of object recognition. Specifically, object priming was eliminated with some combinations of prime and test tasks, and there was no evidence of perceptual (as opposed to conceptual or response) priming in either semantic classification task, even though perceptual identification of the objects is required for at least one of these tasks. Experiment 2 showed that even when perceptual demands were increased by brief presentation, the inside task showed no perceptual priming. Experiment 3 showed that the inside task did not appear to be based on conceptual priming either, as it was not primed significantly when the prime decisions were made to object labels. Experiment 4 showed that visual sensitivity could be restored to the inside task following practice on the task, supporting the suggestion that a critical factor is whether the semantic category is preformed or must be computed. The results show that the visual representational processes revealed by object priming depend crucially on the task chosen.     

Categorical perception of nonspeech sounds by 2-month-old infants

According to recent investigations, adult listeners perceive rise-time differences in both speech and nonspeech stimuli in a categorical manner (Cutting & Rosner, 1974). Adults labeled sawtooth-wave stimuli as either plucked or bowed. The present study uses the high-amplitude sucking technique to explore the 2-month-old infant’s perception of rise-time differences for sawtooth stimuli. Infants discriminated rise-time differences which marked off the different nonspeech categories, but did not discriminate equal differences within either category. Thus, the present study shows that infants, like adults, can perceive nonspeech stimuli in a categorical manner.     

Consumer Motivations for Pursuing Genetic Testing and their Preferences for the Provision of Genetic Services for Hearing Loss

Genetic services for deafness are being increasingly sought due to the introduction of early hearing detection and intervention programs, as well as the rapid progress in the identification of deafness genes. This study aimed to assess the motivations of consumers for pursuing genetic testing as well as their preferences for provision of these services. We conducted 5 focus groups consisting of hearing parents of deaf children, deaf parents, and unmarried deaf adults. Motivations for pursuing genetic testing included determining the etiology, helping to alleviate the guilt associated with the diagnosis of hearing loss in a child, and acquiring information to help them and other family members prepare for the future. Most participants thought that a genetic counselor/geneticist would be the most appropriate professional to provide genetics services. For culturally Deaf individuals, the communication method was seen as more important than the type of professional. Parents preferred that genetic evaluation, including testing, occur either immediately at or a few months after the audiologic diagnosis of hearing loss.     

Tolerance for distorted faces: Challenges to a configural processing account of familiar face recognition

Face recognition is widely held to rely on ‘configural processing’, an analysis of spatial relations between facial features. We present three experiments in which viewers were shown distorted faces, and asked to resize these to their correct shape. Based on configural theories appealing to metric distances between features, we reason that this should be an easier task for familiar than unfamiliar faces (whose subtle arrangements of features are unknown). In fact, participants were inaccurate at this task, making between 8% and 13% errors across experiments. Importantly, we observed no advantage for familiar faces: in one experiment participants were more accurate with unfamiliars, and in two experiments there was no difference. These findings were not due to general task difficulty – participants were able to resize blocks of colour to target shapes (squares) more accurately. We also found an advantage of familiarity for resizing other stimuli (brand logos). If configural processing does underlie face recognition, these results place constraints on the definition of ‘configural’. Alternatively, familiar face recognition might rely on more complex criteria – based on tolerance to within-person variation rather than highly specific measurement.     

Faces retain attention

In the present study, we investigated whether faces have an advantage in retaining attention over other stimulus categories. In three experiments, subjects were asked to focus on a central go/no-go signal before classifying a concurrently presented peripheral line target. In Experiment 1, the go/no-go signal could be superimposed on photographs of upright famous faces, matching inverted faces, or meaningful objects. Experiments 2 and 3 tested upright and inverted unfamiliar faces, printed names, and another class of meaningful objects in an identical design. A fourth experiment provided a replication of Experiment 1, but with a 1,000-msec stimulus onset asynchrony between the onset of the central face/nonface stimuli and the peripheral targets. In all the experiments, the presence of an upright face significantly delayed target response times, in comparison with each of the other stimulus categories. These results suggest a general attentional bias, so that it is particularly difficult to disengage processing resources from faces.     

Dissociating positive and negative influences of verbal processing on the recognition of pictures of faces and objects

Four experiments investigated the role of verbal processing in the recognition of pictures of faces and objects. We used (a) a stimulus-encoding task where participants learned sequentially presented pictures in control, articulatory suppression, and describe conditions and then engaged in an old-new picture recognition test and (b) a poststimulus-encoding task where participants learned the stimuli without any secondary task and then either described or not a single item from memory before the recognition test. The main findings were as follows: First, verbalization influenced picture recognition. Second, there were contrasting influences of verbalization on the recognition of faces, compared with objects, that were driven by (a) the stage of processing during which verbalization took place (as assessed by the stimulus-encoding and poststimulus-encoding tasks), (b) whether verbalization was subvocal (whereby one goes through the motions of speaking but without making any sound) or overt, and (c) stimulus familiarity. During stimulus encoding there was a double dissociation whereby subvocal verbalization interfered with the recognition of faces but not objects, while overt verbalization benefited the recognition of objects but not faces. In addition, stimulus familiarity provided an independent and beneficial influence on performance. Post stimulus encoding, overt verbalization interfered with the recognition of both faces and objects, and this interference was apparent for unfamiliar but not familiar stimuli. Together these findings extend work on verbalization to picture recognition and place important parameters on stimulus and task constraints that contribute to contrasting beneficial and detrimental effects of verbalization on recognition memory.     

Aggressive reactions to abusive supervision: the role of interactional justice and narcissism

In this study, we explore personality and situational conditions in which negative leadership - specifically, abusive supervision - is associated with aggressive behavior in subordinates. That is, we examine the role that interactional justice and narcissism play in an employee's decision to respond aggressively to an abusive supervisor. We demonstrate that interactional justice mediates the relationship between perceptions of abusive supervision and subsequent employee aggression. In addition, we demonstrate that narcissism interacts with interactional justice perceptions to predict workplace aggression. We find that individuals with high levels of narcissism are the employees who are most likely to respond aggressively when they interpret their leader's behavior as abusive.