The effects of different instructions for preparatory muscle tension on simple reaction time

The effects of preparatory weak muscular contraction (pre-tension) have been investigated in a number of previous studies using tasks with either simple or choice responses to measure the reaction time (RT). These studies suggested that optimal pre-tension performed prior to a motor response tends to shorten the RTs. Using a simple RT task in which participants performed a grip response to a visual stimulus, the present study compared the RTs between two pre-tension conditions (self-selection and constraint) to investigate the effects of different instructions for pre-tension. Under the self-selection condition, participants were asked to determine their optimal pre-tension levels while attempting to give responses as fast as possible. Under the constraint condition, the participants developed a pre-tension at a target force determined by the experimenter. The target force was set at the same level as the pre-tension level maintained under the self-selection. Despite the fact that the pre-tension level manipulated was the same for both conditions, the RTs were significantly shorter under self-selection than under constraint. Moreover, the present study showed a positive correlation coefficient between the proportion of shortening in RT and the variation of pre-tension level. This indicated a performance trade-off between the stability of pre-tension and RTs. The result suggests that shorter RTs that occur under self-selection are primarily mediated by mental factors, such as attention allocation, rather than by the effects of peripheral muscular preparation.     

Timing of finger tapping to frequency modulated acoustic stimuli

This study examined the timing of synchronous finger tapping to continuous frequency modulation (FM) and to click trains. Tapping to click trains was found to statistically significantly anticipate the acoustic stimulus. Tapping to continuous FM occurred before the instantaneous frequency rose through its mean value (i.e. at zero phase of the sinusoidal FM). The anticipation of zero phase of the FM was similar in magnitude to the anticipation of the click stimuli. However, there was a systematic departure from this timing when the FM depth was varied, the cause of which is unclear. The perceived timing of acoustic stimuli will influence the timing of motor responses to the stimuli. These results may therefore be relevant to the timing of perceptual centres of acoustic stimuli including speech.     

Cross-Sectional and Longitudinal Relations Among Children's Trust Beliefs,Psychological Maladjustment and Social Relationships: Are Very High as Well as Very Low Trusting Children at Risk?

Four hundred and thirty-four children enrolled in school years 5 and 6 in the United Kingdom were administered measures of trust beliefs in peers/best friends and psychosocial functioning (internalized maladjustment, self-perceived social acceptance, social preference, and social exclusion) across an 8-month period (mean age = 9 years − 9 months at Time 1). The relation between children's trust beliefs in peers or trust beliefs within best friend dyads and measures of psychosocial functioning conformed to a quadratic pattern. Compared to children in the middle range of trust beliefs, children with very low trust beliefs and those with very high trust beliefs in peers and/or within best friend dyads displayed higher internalized maladjustment, lower self-perceived social acceptance, higher social exclusion, and lower social preference. The relation between the trust beliefs and internalized maladjustment was asymmetrical, with children who held very low trust beliefs being comparatively more disadvantaged.     

A primitive memory system for the deployment of transient attention

When transient attention is summoned by the sudden appearance of a large cue, it can be deployed to a small portion of the cue where a target appeared on previous trials (Kristjánsson, Mackeben, & Nakayama, 2001). This result runs counter to the view that transient, or exogenous, attention is summoned automatically and indiscriminately to abruptly appearing stimuli. To further characterize the short-term learning mediating this phenomenon, we report the following results. (1) When there was a consistent relationship between a small identifying portion of the cue and the target, learning occurred rapidly. Thus, transient attention can be summoned to a distinctively colored or distinctively shaped portion of the cue as a consequence of repeated pairing (Experiments 1 and 2). (2) When there was a consistent relation between a given position on the object and its overall color or shape, no learning occurred (Experiments 3 and 4). Thus, transient attention cannot learn a complex relation between target position and shape or color. (3) We confirmed the fast object-centered learning of position shown in Kristjánsson et al. (2001). (4) Explicit knowledge of the cue-target relationship had no effect on the performance of the task. The results provide evidence for the existence of a primitive object-centered learning mechanism beneficial for the rapid deployment of transient attention. The possible role of such a mechanism in the maintenance of representations of the visual environment is discussed.     

Normal recognition of emotion in a prosopagnosic

In the leading model of face perception, facial identity and facial expressions of emotion are recognized by separate mechanisms. In this report, we provide evidence supporting the independence of these processes by documenting an individual with severely impaired recognition of facial identity yet normal recognition of facial expressions of emotion. NM, a 40-year-old prosopagnosic, showed severely impaired performance on five of six tests of facial identity recognition. In contrast, she performed in the normal range on four different tests of emotion recognition. Because the tests of identity recognition and emotion recognition assessed her abilities in a variety of ways, these results provide solid support for models in which identity recognition and emotion recognition are performed by separate processes.     

Beliefs and sentences in the head

It is argued thatde dicto andde re beliefs are attitudes towards syntactically structured entities (sentences) in the head. In order to identify the content of ade dicto orde re belief, we must be able to match causal relations of belief states to natural language inferences. Such match-ups provide sufficient empirical justification for regarding those causal relations as syntactic transformations, that is, inferences. But only syntactically structured entities are capable of enjoying such inferential relations. Hence,de dicto andde re beliefs must be syntactically structured. Given that beliefs are also brain states, it follows that they are sentences in the brain. The argument presented here is shown to be an improvement over similar arguments advanced by Harman and Fodor.Thanks to George Schlesinger, Ann MacKenzie, Vic Tennant and an anonymous referee forSynthese for helpful comments on an earlier draft of this paper.     

The figurative and literal senses of idioms,or all idioms are not used equally

Two groups of college students (40 and 56) gave what they felt to be the literal and figurative interpretation of 30 different idiomatic expressions and rated their interpretations for frequency of use and for familiarity. Ratings were done on 7-point scales where 1=never and 7=very often. Subjects gave higher ratings to figurative interpretations than to literal interpretations and higher ratings of frequency than familiarity. Nevertheless, there was a high correlation between ratings of frequency and familiarity. It was also found that figurative ratings were independent of literal ratings. In the main, figurative ratings were found to be high (5–7) irrespective of their literal ratings. A small subgroup of idioms, however, had relatively low ratings on both scales. The differences noted between idioms may help to account for certain discrepancies that have appeared in recent experimental studies on idiom processing.     

An Investigation of the Structural Validity of Loevinger's Model and Measure of Ego Development

This study demonstrates the use of structural equation modeling for investigating a hierarchical model of personality based on Loevinger's (1976) conceptualization. This model was constructed to have a multifactorial and hierarchical structure in which the ego development construct served as the source of covariation for specific personality constructs of impulse control, interpersonal style, conscious preoccupations, and cognitive style. This model and three other conceivable models were investigated to determine which structure best represented the relations among specific personality constructs and ego development. The specific personality constructs were identified by measures chosen from the available pool of measures that were compatible with Loevinger's conceptualization. The four conceivable models were fitted to sample data from 267 adult subjects using confirmatory factor analysis and were compared with indices of model fit and methods for comparison of nested models. Results suggested that the four specific personality constructs and ego development are part of the same process. Although a hierarchical structure appeared tenable for this process, the role of ego development perhaps is not as dominant as envisioned by Loevinger. These results must be considered tentative due to measurement limitations.