Brain activity differentiates face and object processing in 6-month-old infants.

Event-related potentials were used to determine whether infants, like adults, show differences in spatial and temporal characteristics of brain activation during face and object recognition. Three aspects of visual processing were identified: (a) differentiation of face vs. object (P400 at occipital electrode was shorter latency for faces), (b) recognition of familiar identity (Nc, or negative component, at fronto-temporal electrodes [FTEs] was of larger amplitude for familiar stimuli), and (c) encoding novelty (slow wave at FTEs was larger for unfamiliar stimuli). The topography of the Nc was influenced by category type: Effects of familiarity were limited to the midline and right anterior temporal electrodes for faces but extended to all temporal electrodes for objects. Results show that infants' experience with specific examples within categories and their general category knowledge influence the neural correlates of visual processing.     

Task experience and children's working memory performance: a perspective from recall timing

Working memory is an important theoretical construct among children, and measures of its capacity predict a range of cognitive skills and abilities. Data from 9- and 11-year-old children illustrate how a chronometric analysis of recall can complement and elaborate recall accuracy in advancing our understanding of working memory. A reading span task was completed by 130 children, 75 of whom were tested on 2 occasions, with sequence length either increasing or decreasing during test administration. Substantial pauses occur during participants' recall sequences, and they represent consistent performance traits over time, while also varying with recall circumstances and task history. Recall pauses help to predict reading and number skills, alongside as well as separate from levels of recall accuracy. The task demands of working memory change as a function of task experience, with a combination of accuracy and response timing in novel task situations being the strongest predictor of cognitive attainment.     

Risk for suicidal thoughts and behavior after childhood sexual abuse in women and men

Earlier studies have found an elevated risk for psychopathology and suicidal behavior associated with childhood sexual abuse (CSA); however, the degree to which risk is mediated by depression and posttraumatic stress disorder (PTSD) in women and men remains unclear. We examined these issues in data from a family study of childhood maltreatment (N = 2,559). We found significant CSA-associated risk for depression, PTSD, and suicidal behavior for women and men. In survival analyses controlling for these disorders, we observed persistent but somewhat reduced CSA-associated risk for suicidal ideation and suicide attempt. Our findings suggest that these disorders partially mediate CSA-associated risk.     

List composition and the word length effect in immediate recall: A comparison of localist and globalist assumptions

Lists of short words usually are recalled better than lists of longer words in immediate recall tasks. Such word length effects might be explained by localist accounts, in which the length of each word in a list affects the recall of that word only, or by globalist accounts, in which the lengths of at least some words affect the recall of other words (e.g., Baddeley, 1986). In a recent localist account, Neath and Nairne (1995) proposed that the recall of each word depends on the likelihood that features within the word are contaminated within the memory representation. We tested this by presenting not only homogeneous lists of short and long words, but also mixed lists, and by including articulatory suppression on some trials. The short-word advantage depended on the composition of the list, ruling out a strictly localist approach. There appear to be several globalist influences on recall, including distinctiveness factors as well as phonological storage and articulation.     

The interpretation of symptoms of severe dietary restraint

A recent cognitive-behavioural theory of eating disorders proposes that people with eating disorders interpret symptoms of dietary restraint in terms of control. The primary aim of the present study was to test this hypothesis. A second aim was to test the hypothesis derived from clinical observation that people with eating disorders view these symptoms positively. Forty-four participants meeting DSM-IV criteria for a clinical eating disorder and 80 control participants with no history of an eating disorder completed an ambiguous scenario paradigm and self-report measures of eating disorder features and depression. Patients with eating disorders were significantly more likely to interpret symptoms of dietary control in terms of control, providing support for the cognitive-behavioural theory. There was only partial support for the second hypothesis. The implications for the new cognitive-behavioural theory and therapy are discussed.     

The influence of postural emotion cues on implicit trait judgements

Perceptions of others’ traits (e.g., trustworthiness or dominance) are influenced by the emotion displayed on their face. For instance, the same individual appears more trustworthy when they express happiness than when they express anger. This overextension of emotional expressions has been shown with facial expression but whether this phenomenon also occurs when viewing postural expressions was unknown. We sought to examine how expressive behaviour of the body would influence judgements of traits and how sensitivity to this cue develops. In the context of a storybook, adults (N?=?35) and children (5 to 8 years old; N?=?60) selected one of two partners to help face a challenge. The challenges required either a trustworthy or dominant partner. Participants chose between a partner with an emotional (happy/angry) face and neutral body or one with a neutral face and emotional body. As predicted, happy facial expressions were preferred over neutral ones when selecting a trustworthy partner and angry postural expressions were preferred over neutral ones when selecting a dominant partner. Children’s performance was not adult-like on most tasks. The results demonstrate that emotional postural expressions can also influence judgments of others’ traits, but that postural influence on trait judgments develops throughout childhood.

     

When does grouping happen?

Recent research on perceptual grouping is described with particular emphasis on identifying the level(s) at which grouping factors operate. Contrary to the classical view of grouping as an early, two-dimensional, image-based process, recent experimental results show that it is strongly influenced by phenomena related to perceptual constancy, such as binocular depth perception, lightness constancy, amodal completion, and illusory contours. These findings imply that at least some grouping processes operate at the level of phenomenal perception rather than at the level of the retinal image. Preliminary evidence is reported showing that grouping can affect perceptual constancy, suggesting that grouping processes must also operate at an early, preconstancy level. If so, grouping may be a ubiquitous, ongoing aspect of visual organization that occurs for each level of representation rather than as a single stage that can be definitively localized relative to other perceptual processes.     

Allocation of self-paced study time and the "labor-in-vain effect"

This research explored the possibility that a metacognitive control process (namely, the allocation of self-paced study time) might be affected by the output from metacognitive monitoring processes (i.e., ease-of-learning and/or feeling-of-knowing judgments). In three experiments, university undergraduates received instructions that emphasized either accuracy of learning or speed of learning. The major findings were: (a) ease-of-learning judgments and feeling-of-knowing judgments are reliably related to study-time allocation, with more self-paced study time being allocated to the supposedly more difficult items; (b) even when instructed to master every item and when allowed unlimited study time to do so, people terminate study before learning is completed; and (c) large increases in self-paced study time can yield little or no increase in the subsequent likelihood of recall (the "labor-in-vain effect"). Implications are drawn for a model of the interplay between metacognitive monitoring processes and metacognitive control processes.     

Lexical and semantic search in cued recall, fragment completion, perceptual identification, and recognition

Search processes in word-stem cued recall, fragment completion, perceptual identification, and recognition are contrasted. These retention tests involve letters as cues, but the lexical characteristics of these cues vary considerably. In word-stem cued recall, ending letters are presented as recall cues for studied targets (e.g., ONEY as a cue for HONEY). In fragment completion, the test cues consist of letters and spaces (e.g., HO__Y); in perceptual identification, they consist of letter features that survive the mask; and in recognition, they consist of all the letters of the studied word (e.g., HONEY). These differences in retention tests and lexical characteristics were evaluated by manipulating three variables with known effects in cued recall: (a) the presence of study context words emphasizing lexical information, (b) lexical set size corresponding to the number of words that fit the letter cue, and (c) meaning set size corresponding to the number of meaningful associates linked to the studied targets. The results indicated that (a) the presence of study contexts emphasizing lexical information reduced accuracy and response time equally in all tasks, (b) larger lexical set sizes reduced accuracy and response time in all tasks except recognition, and (c) larger meaning set size reduced accuracy in cued recall but not in the other tasks. Lexical search appears to be a significant component process in word-stem cued recall, fragment completion, and identification. Searching through meaning-related concepts encoded during study is a significant component process only in cued recall.