Challenge point: a framework for conceptualizing the effects of various practice conditions in motor learning

The authors describe the effects of practice conditions in motor learning (e.g., contextual interference, knowledge of results) within the constraints of 2 experimental variables: skill level and task difficulty. They use a research framework to conceptualize the interaction of those variables on the basis of concepts from information theory and information processing. The fundamental idea is that motor tasks represent different challenges for performers of different abilities. The authors propose that learning is related to the information arising from performance, which should be optimized along functions relating the difficulty of the task to the skill level of the performer. Specific testable hypotheses arising from the framework are also described.     

Prepared movements are elicited early by startle

A startle stimulus has been shown to elicit a ballistic response in a reaction time (RT) task at very short latencies without involvement of the cerebral cortex (J. Valls-Sole, J. C. Rothwell, F. Gooulard, G. Cossu, & E. Munoz, 1999). The present authors examined the nature of the startle response. A simple RT task was used in which 8 participants performed arm extension movements to 3 target distances (20 degrees, 40 degrees, and 60 degrees ) in a blocked design. An unpredictable startling acoustic stimulus (124 dB) replaced the imperative stimulus in certain trials. The authors verified the presence of a startle response independent from the prepared response by observing electromyographic (EMG) activity in sternocleidomastoid and orbicularis oculi muscles. Findings indicated that when the participant was startled, the intended voluntary response was produced at significantly shorter response latencies. Furthermore, the kinematic variables of the observed response during startle trials for all 3 target distances were mostly unchanged. The EMG characteristics of the responses were not modified, indicating that the response produced was indeed the prepared and intended response.     

Correlates of aggression in African American and Puerto Rican children

The authors examined a cross-sectional interrelationship of psychosocial domains as they relate to aggression in a group of African American and English-speaking Puerto Rican children living in New York City. The population included 80 biological children of African American and Puerto Rican young adults who had been participating in the authors' ongoing longitudinal study, and 77 mothers or mother substitutes (rearing mothers) of those children. The authors performed hierarchical multiple regression analysis. The results indicated that (a) the child's personality and maternal attributes were significantly related to the child's aggression, despite control on all of the other domains and (b) the ethnic identification and discrimination domain was no longer related to the child's aggression with control on the mother-child relationship domain or on the child's personality domain. The findings have implications for clinical practice and public policy.     

A six-factor structure of personality-descriptive adjectives: solutions from psycholexical studies in seven languages

Standard psycholexical studies of personality structure have produced a similar 6-factor solution in 7 languages (Dutch, French, German, Hungarian, Italian, Korean, Polish). The authors report the content of these personality dimensions and interpret them as follows: (a) a variant of Extraversion, defined by sociability and liveliness (though not by bravery and toughness); (b) a variant of Agreeableness, defined by gentleness, patience, and agreeableness (but also including anger and ill temper at its negative pole); (c) Conscientiousness (emphasizing organization and discipline rather than moral conscience); (d) Emotionality (containing anxiety, vulnerability, sentimentality, lack of bravery, and lack of toughness, but not anger or ill temper); (e) Honesty-Humility; (f) Intellect/Imagination/Unconventionality. A potential reorganization of the Big Five factor structure is discussed.     

Discrete emotions and persuasion: the role of emotion-induced expectancies

The authors argue that specific emotions can alter the persuasive impact of messages as a function of the emotional framing of persuasive appeals. Because specific emotions inflate expectancies for events possessing matching emotional overtones (D. DeSteno, R. E. Petty, D. T. Wegener, & D. D. Rucker, 2000), the authors predicted that attempts at persuasion would be more successful when messages were framed with emotional overtones matching the emotional state of the receiver and that these changes would be mediated by emotion-induced biases involving expectancies attached to arguments contained in the messages. Two studies manipulating discrete negative emotional states and message frames (i.e., sadness and anger) confirmed these predictions. The functioning of this emotion-matching bias in parallel with emotion-induced processing differences and the limitations of a valence-based approach to the study of attitude change are also considered.     

The effect of daily stress, personality, and age on daily negative affect

The current study examined whether stress reactivity becomes stronger or weaker with age. Daily stress and daily negative affect were modeled using 1,012 subjects from the National Study of Daily Events (NSDE), an 8-day daily diary study. Age ranged from 25 to 74. Data were modeled using within-person HLM techniques. Daily stress and neuroticism interacted in their effect on daily negative affect. There was a stronger association between daily stress and negative affect for persons high in neuroticism as compared to those low on the trait. In addition, daily stress and age interacted in their effect on daily negative affect. There was a stronger association between daily stress and negative affect for older as compared to younger adults. Results suggest heightened reactivity to stressors in older adulthood, perhaps due to kindling effects. Changes in the aging brain may explain this effect. Our investigations illuminate the complexities that characterize the set of associations among negative affect, stress, personality, and age, and point to potential aging or cohort effects.     

Hostility and facial affect recognition: effects of a cold pressor stressor on accuracy and cardiovascular reactivity

The effects of hostility and a cold pressor stressor on the accuracy of facial affect perception were examined in the present experiment. A mechanism whereby physiological arousal level is mediated by systems which also mediate accuracy of an individual’s interpretation of affective cues is described. Right-handed participants were classified as high hostile (N=28) or low hostile (N=28) using the Cook Medley Hostility Scale. The high-hostile group met joint selection criteria. Only high-hostile participants who showed cardiovascular reactivity to the cold pressor, with systolic BP change exceeding the group mean were included. Groups were further subdivided into cold pressor and non-cold pressor test conditions. It was predicted that high-hostile men, relative to low-hostile men, would show decreased perceptual accuracy when presented with happy, angry, and neutral facial configurations within the left visual field (LVF). Results indicated that high-hostile men were less accurate than low-hostile men in the LVF. Further, pre-stress accuracy scores in the high-hostile men were similar to the post-stress accuracy scores of the low-hostile men. The lateralization of affective function and the role of physiological arousal in affective facial perception are discussed.     

Using recall to reduce false recognition: diagnostic and disqualifying monitoring

Whether recall of studied words (e.g., parsley, rosemary, thyme) could reduce false recognition of related lures (e.g., basil) was investigated. Subjects studied words from several categories for a final recognition memory test. Half of the subjects were given standard test instructions, and half were instructed to use recall to reduce false recognition. Manipulation checks indicated that the latter instructions did elicit a recall-to-reject strategy. However, false recognition was selectively reduced only when all the words from a category could be recalled (Experiment 1). When longer categories were used, thereby minimizing exhaustive recall, a recall-to-reject strategy was ineffective at reducing false recognition (Experiment 2). It is suggested that exhaustively recalling a category allowed subjects to disqualify the lure as having occurred, analogous to recall-to-reject demonstrations in other tasks. In contrast, partially recalling a category did not help to diagnose the lure as nonstudied. These findings constrain theories of recall-based monitoring processes.     

Intentional control and implicit sequence learning

Sequence knowledge acquired by repeated exposure to targets in a speeded localization task was studied in 3 experiments that sought to test A. Destrebecqz and A. Cleeremans's (2001, 2003) claim that, under certain circumstances, the expression of such sequence knowledge cannot be brought under intentional control. In Experiment 1 participants were trained on either a deterministic or a probabilistic sequence and then performed a free-generation test under either inclusion or exclusion instructions. Participants were found to be capable of both expressing (inclusion) and avoiding expressing (exclusion) sequence knowledge. These results were confirmed in Experiment 2 with a more exact replication of Destrebecqz and Cleeremans's methodology. In Experiment 3 participants performed a trial-by-trial generation test under both inclusion and exclusion conditions after a much longer period of training. All the findings are consistent with the proposal that information acquired during sequence learning is explicit in nature.     

Inconsistency in serial choice decision and motor reaction times dissociate in younger and older adults

Intraindividual variability (inconsistency) in reaction time (RT) latencies was investigated in a group of younger (M=25.46 years) and older (M=69.29 years) men. Both groups performed 300 trials in 2-, 4-, and 8-choice RT conditions where RTs for decision and motor components of the task were recorded separately. A dissociation was evident in that inconsistency was greater in older adults for decision RTs when task demands relating to the number of choices and fatigue arising from time-on-task were high. For younger persons, a weak trend toward greater inconsistency in motor RTs was evident. The results are consistent with accounts suggesting that inconsistency in neurobiological mechanisms increases with age, and that attentional lapses or fluctuations in executive control contribute to RT inconsistency.