Temporal kinetics of prefrontal modulation of the extrastriate cortex during visual attention

Single-unit, event-related potential (ERP), and neuroimaging studies have implicated the prefrontal cortex (PFC) in top-down control of attention and working memory. We conducted an experiment in patients with unilateral PFC damage (n=8) to assess the temporal kinetics of PFC-extrastriate interactions during visual attention. Subjects alternated attention between the left and the right hemifields in successive runs while they detected target stimuli embedded in streams of repetitive task-irrelevant stimuli (standards). The design enabled us to examine tonic (spatial selection) and phasic (feature selection) PFC-extrastriate interactions. PFC damage impaired performance in the visual field contralateral to lesions, as manifested by both larger reaction times and error rates. Assessment of the extrastriate P1 ERP revealed that the PFC exerts a tonic (spatial selection) excitatory input to the ipsilateral extrastriate cortex as early as 100 msec post stimulus delivery. The PFC exerts a second phasic (feature selection) excitatory extrastriate modulation from 180 to 300 msec, as evidenced by reductions in selection negativity after damage. Finally, reductions of the N2 ERP to target stimuli supports the notion that the PFC exerts a third phasic (target selection) signal necessary for successful template matching during postselection analysis of target features. The results provide electrophysiological evidence of three distinct tonic and phasic PFC inputs to the extrastriate cortex in the initial few hundred milliseconds of stimulus processing. Damage to this network appears to underlie the pervasive deficits in attention observed in patients with prefrontal lesions.     

The effect of manipulated sympathy and anger on left and right frontal cortical activity

The present research extended past research demonstrating that approach-motivated anger is associated with greater left than right frontal cortical activity. Because past research had examined difference scores between left and right frontal activity, it was unable to test whether approach-motivated anger increased left activity, decreased right activity, or both. In addition, the present research examined a potential moderator of the effect of insult on left frontal activity. That is, it tested whether sympathy for an insulting person would reduce the left frontal activity that occurs following being insulted. Results indicated that left frontal activity was increased and right frontal activity was decreased by the insult. Moreover, these effects were inhibited when high levels of sympathy were first aroused.     

Career benefits associated with mentoring for protégeé: a meta-analysis

Meta-analysis was used to review and synthesize existing empirical research concerning the career benefits associated with mentoring for the protégé. Both objective (e.g., compensation) and subjective (e.g., career satisfaction) career outcomes were examined. Comparisons of mentored versus nonmemored groups were included, along with relationships between mentoring provided and outcomes. The findings were generally supportive of the benefits associated with mentoring, but effect sizes associated with objective outcomes were small. There was also some indication that the outcomes studied differed in the magnitude of their relationship with the type of mentoring provided (i.e. career or psychosocial).     

The use of a distractor-assigned response slows later responding in a location negative priming task

Responding to a target's location takes longer when that location has recently contained a distractor event (ignored-repetition [IR] trial) relative to when it has been unoccupied (control trial). This is known as the location negative priming (NP) effect. We aimed to determine whether the elevated reaction time observed for IR trials was due to the reuse of a distractor location (location locus) and/or to the need to execute a (just inhibited) distractor response (response locus). We isolated these loci latency effects by using many-to-one and one-to-many location-response assignments. Our results showed that reusing a distractor location hastened target processing at that position (facilitative location locus), whereas the production of a distractor response was associated with a time cost (interfering response locus). Accordingly, part of the latency elevation seen with IR trials results from the need on these occasions to execute ajust inhibited (distractor) response, and, hence, the location NP effect has a response locus.     

Competitive martial arts and aggressiveness: a 2-yr. longitudinal study among young boys

This study is a follow-up study of Reynes and Lorant's studies assessing the effect of one year of judo and karate training on aggressiveness scores among young boys. The data reported here were obtained after a second year of practice, 14 judoka, 9 karateka, and 20 control participants who filled out the Buss-Perry Aggression Questionnaire three times, 1 year apart. At the first assessment, all participants, born the same year, were 8 yr. old and at the third they were 10 yr. old. Analysis indicated that after two years of practice, karate training seemed to have neither positive nor negative effects on aggressiveness scores, while judo training seemed to have a negative effect on anger scores. However, the results suggested the importance of kata or meditation in training sessions on self-control acquisition for such young boys.     

Effects of redundant visual stimuli on temporal order judgments

Four experiments were conducted in order to compare the effects of stimulus redundancy on temporal order judgments (TOJs) and reaction times (RTs). In Experiments 1 and 2, participants were presented in each trial with a tone and either a single visual stimulus or two redundant visual stimuli. They were asked to judge whether the tone or the visual display was presented first. Judgments of the relative onset times of the visual and the auditory stimuli were virtually unaffected by the presentation of redundant, rather than single, visual stimuli. Experiments 3 and 4 used simple RT tasks with the same stimuli, and responses were much faster to redundant than to single visual stimuli. It appears that the traditional speedup of RT associated with redundant visual stimuli arises after the stimulus detection processes to which TOJs are sensitive.     

Australian lawyers' views on competency issues in older adults

Lawyers are often called upon by their older clients to draft contracts, make up wills or powers of attorney, or provide other forms of legal advice or service. With the increasing numbers of older people in the population, the numbers of older clients for legal practitioners is likely to increase. Older people are also at increased risk for impaired cognitive processes that can affect their ability to make reasoned judgements in civil contracts and other legal arrangements. Here we report on the results of a survey of 302 Australian solicitors as to their experience and practices in determining the capacity of older clients to make legal decisions. The responses, reflecting a 20.7% return rate, showed a wide range of experience in conducting capacity assessments, with a mean of 15.7 years (SD = 10.59). There was a very wide range of practices in determining capacity with no consensus. The most frequent form of questions older clients were asked related to personal and family history. Less than one-quarter asked for the rationale of the decision: the most appropriate form of question in the literature. The results suggest a need for further training of solicitors in the assessment of the capacity of older clients to make legal decisions.