Human bilateral deficit during a dynamic multi-joint leg press movement

Bilateral deficit has been used to describe the phenomenon of a reduction in performance during synchronous bilateral movements when compared to the sum of identical unilateral movements. The study of bilateral deficit in humans under isometric, and to a lesser extent, dynamic conditions has shown bilateral decreases in force and muscle activation, and delayed reaction time. Results are equivocal, however, and biomechanical analyses of dynamic conditions, i.e., movements, are lacking. Our purpose was to determine, through an analysis of kinematic, kinetic, and electromyographic (EMG) data, whether or not bilateral deficit was present during a dynamic multi-joint movement under conditions where the external load was relatively equal for unilateral and bilateral efforts. Five male participants performed repeated unilateral and bilateral maximal horizontal leg press jumps under 100% (1BW) and 200% (2BW) relative body weight loads. Significant bilateral deficits in resultant ground reaction impulse of 27.7% and 13.0% were present in 1BW and 2BW, respectively. Maximum joint power at the hip exhibited significant deficits in both 1BW and 2BW of 35.6% and 25.1%, respectively. In both 1BW and 2BW conditions, ankle (15.5% and 11.5%), knee (10.9% and 5.7%), and hip (38.5% and 30.4%) work was significantly affected. Statistically significant EMG bilateral deficits were found in every muscle in both conditions except for rectus femoris during the 2BW trials. Bilateral deficit values ranged from 9.1% to 20.9% for 1BW, while deficits between 6.1% and 20.7% were found in 2BW. These results indicate that during dynamic leg press, bilateral deficit does exist, but that individual muscle activation levels and joint kinetics are not equally affected.     

Characterizing the ADHD phenotype for genetic studies

The genetic study of ADHD has made considerable progress. Further developments in the field will be reliant in part on identifying the most appropriate phenotypes for genetic analysis. The use of both categorical and dimensional measures of symptoms related to ADHD has been productive. The use of multiple reporters is a valuable feature of the characterization of psychopathology in children. It is argued that the use of aggregated measures to characterize the ADHD phenotype, particularly to establish its pervasiveness, is desirable. The recognition of the multiple comorbidities of ADHD can help to isolate more specific genetic influences. In relation to both reading disability and conduct disorder there is evidence that genes may be involved in the comorbid condition that are different from pure ADHD. To date, progress with the investigation of endophenotypes for ADHD has been disappointing. It is suggested that extending such studies beyond cognitive underpinnings to include physiological and metabolic markers might facilitate progress.     

Psychological factors and use of antiepileptic drugs: pilot work using an objective measure of adherence

Given the current emphasis on the "concordance" prescribing model, a study was designed to determine the influence of patients' beliefs about epilepsy, beliefs about medication and a range of neuroepilepsy variables on drug adherence among a sample of epilepsy patients. A special feature of the study was the use of a credible objective measure of drug adherence. Psychological health was also assessed. Thirty-seven patients were recruited from a local epilepsy clinic. Beliefs about epilepsy (illness representations), beliefs about epilepsy medication, anxiety, depression, neuroepilepsy status and adherence were all measured. Data were collected via clinical interview and questionnaire methods. Adherence with drug treatment was determined by an objective measure using low-dose phenobarbital as an indicator of adherence and, or, measurement of antiepileptic drug levels. Neither illness representations nor beliefs about epilepsy drugs were related to adherence. With the exception of time since last seizure, which was positively related to adherence, neuroepilepsy variables were unrelated to adherence. A number of significant associations between cognitive representations of epilepsy and mood were found.     

Movement adaptations in 7- to 10-year-old typically developing children: evidence for a transition in feedback-based motor control

We used a modified double-step pointing task to study movement adaptations in 7- to 10-year-old typically developing children. We found that the majority (63%) were able to optimally adapt fast, goal-directed visually-guided movements to a late change in target location meeting the requirements of speed and accuracy. A minority (35%) failed to meet the requirement of accuracy resulting in a less optimal adaptation. The results showed that the ability to adapt movements optimally develops before the age of 7 years in typically developing children. Literature proposes a transition in development of motor control around the age of 8 years. The present results replicate and extend this by suggesting that this transition affects the later phases of fast, goal-directed visually-guided movements rather than the early phases, such as movement programming and acceleration. Finally, the results indicate that the optimally adapted movements were the result of a specific strategy in which a specific component of movement execution was slowed on all trials. This suggests that 7- to 10-year-old typically developing children have developed implicit knowledge about which movement components are the most efficient to adapt.     

Selecting Unskilled and Semi‐Skilled Blue‐Collar Workers: The criterion‐related validity of the PDI‐employment inventory1

Two concurrent criterion‐related validity studies were conducted with blue‐collar workers employed in Australia. The first sample consisted of 77 unskilled and semi‐skilled manufacturing employees. The second sample consisted of 243 stockpeople who worked in piggeries. A range of work‐related criteria was used, and this range differed across the two studies. The results showed that Employment Inventory–Performance was a reasonable predictor of some aspects of supervisor ratings of work performance but unrelated to other aspects. A similar pattern of findings emerged with self‐ratings of work performance. Employment Inventory–Tenure was weakly related to turnover intentions and actual turnover.     

When does prior knowledge disproportionately benefit older adults’ memory?

Material consistent with knowledge/experience is generally more memorable than material inconsistent with knowledge/experience – an effect that can be more extreme in older adults. Four experiments investigated knowledge effects on memory with young and older adults. Memory for familiar and unfamiliar proverbs (Experiment 1) and for common and uncommon scenes (Experiment 2) showed similar knowledge effects across age groups. Memory for person-consistent and person-neutral actions (Experiment 3) showed a greater benefit of prior knowledge in older adults. For cued recall of related and unrelated word pairs (Experiment 4), older adults benefited more from prior knowledge only when it provided uniquely useful additional information beyond the episodic association itself. The current data and literature suggest that prior knowledge has the age-dissociable mnemonic properties of (1) improving memory for the episodes themselves (age invariant), and (2) providing conceptual information about the tasks/stimuli extrinsically to the actual episodic memory (particularly aiding older adults).     

Screening for eating disorders in primary care: EDE-Q versus SCOFF

OBJECTIVE AND METHODS: The comparative validity of the Eating Disorder Examination Questionnaire (EDE-Q) (22 items) and SCOFF (five items) in screening for cases of the more commonly occurring eating disorders was examined in a primary care sample of young adult women (n=257). Diagnoses were confirmed in a sub-group of interviewed participants (n=147). RESULTS: Twenty-five cases, primarily variants of bulimia nervosa (BN) not meeting formal diagnostic criteria, were identified in the interviewed sample. An EDE-Q global score of >or= 2.80 yielded the optimal trade-off between sensitivity (Se) (0.80) and specificity (Sp) (0.80) (positive predictive value (PPV)=0.44), whereas a score of two or more positive responses on the SCOFF was optimal (Se=0.72, Sp=0.73, PPV=0.35). Validity coefficients for both measures varied as a function of participants' age and body weight, although these effects were more pronounced for the SCOFF. CONCLUSIONS: Both measures performed well in terms of their ability to detect cases and to exclude non-cases of the more commonly occurring eating disorders in a primary care setting. The EDE-Q performed somewhat better than the SCOFF and was more robust to effects on validity of age and weight. These findings need to be weighed against the advantage of the SCOFF in terms of its brevity.