The effects of skill focused instructions on walking performance depend on movement constraints in Parkinson's disease.

Previous research has shown that skill focused attention may be beneficial for the performance of complicated motor tasks in individuals with Parkinson's disease (PD). The objective of this study was to assess the impact of skill focused attention instructions on gait under temporal movement constraints that may reflect common challenges experienced in daily life. Eighteen patients with PD walked a straight pathway under two different attention focus conditions (no instruction, skill focused instruction) and two different walking speeds (preferred pace, as fast as possible). In the no instruction condition, patients were not told "where" attention should be directed. In the skill focused instruction condition, patients were told to focus on the foot contacting the floor with each step. Spatial and temporal gait measures, as well as, trunk sway were used to quantify walking performance. The results showed that when walking at a preferred pace, skill focused instructions benefited gait performance (e.g., increased gait velocity, larger steps, more trunk sway). However, when walking as fast as possible, skill focused instructions had the opposite effect on gait performance (e.g., decreased gait velocity, smaller steps, and less trunk sway). This study demonstrates that skill focused instructions may contribute to the prioritization of stability under imposed temporal movement constraints. Clinicians should be aware of the processes involved in prioritization of movement components versus task goals in PD and the potential application of an attention based instructional set in altering priorities in this population.

Directional effects of biofeedback on trunk sway during stance tasks in healthy young adults.

Biofeedback has been shown to improve balance in a number of different populations. As certain clinical populations have a tendency to fall in one direction, the provision of biofeedback in the impaired direction may improve balance in that direction but not in others. The purpose of this study was to determine the effects of uni-directional biofeedback on stance tasks in healthy young adults. Trunk sway was measured in 40 healthy young adults as they performed nine stance tasks with and without biofeedback. Participants received biofeedback about their trunk sway in either the anterior-posterior (AP) or medial-lateral (ML) direction using a multi-modal head-mounted biofeedback device. An overall effect of reduced sway angle and increased sway angular velocity was noted with biofeedback. Some of the effects of biofeedback were dependent on the direction in which biofeedback was given and whether vision was present during the stance task. These effects were strongest in the pitch direction for AP biofeedback with vision present. This study showed direction specific effects of biofeedback are greatest in the sagittal plane. These results are important clinically as the use of biofeedback during stance tasks, similar to gait tasks, appears to work best in the AP direction when vision is present.

Alexithymia and pain in three chronic pain samples: comparing Caucasians and African Americans.

OBJECTIVE: African Americans often report greater pain than do Caucasians, but the factors responsible for this discrepancy are not known. We examined whether alexithymia-the trait of difficulty identifying and describing one's feelings and lacking introspection-may contribute to this ethnic group difference. We tested whether the mean level of alexithymia is higher, and whether alexithymia and pain are more highly correlated, among African Americans than among Caucasians in patients with chronic pain disorders. DESIGN: Three cross-sectional, correlational studies were conducted on three separate samples of patients with chronic pain. Analyses examined the full sample and then Caucasians and African Americans separately. SETTING AND PATIENTS: Patients were recruited primarily from treatment settings. Samples were patients with rheumatoid arthritis (N = 155), migraine headaches (N = 160), or systemic lupus erythematosus (N = 123), and each sample included only Caucasians or African Americans. MEASURES: The Toronto Alexithymia Scale-20 assessed global alexithymia and three alexithymia facets. Pain severity, functional disability, or symptoms were also measured on each sample. RESULTS: Similar findings occurred across all three samples. African Americans had only slightly higher mean alexithymia levels than did Caucasians, and this was partly accounted for by socioeconomic differences between groups. More importantly, alexithymia correlated only weakly with pain or symptom severity for each full sample, but the two ethnic groups showed different patterns. Alexithymia correlated positively with pain severity among African Americans, but was uncorrelated with pain among Caucasians, even after covarying for various socioeconomic variables. CONCLUSIONS: Alexithymia is more correlated with pain severity among African Americans with chronic pain disorders than among Caucasians, potentially contributing to the higher pain reports among African Americans.

Do others really know us better? Predicting migraine activity from self- and other-ratings of negative emotion.

OBJECTIVE: The validity of self-reported negative emotion to predict health status is limited by response biases, introspection limitations, and methodological confounds. The reports of significant others about the patients' negative emotion may circumvent these limitations. This study sought to compare the validity of self- versus other-reported negative emotion as a correlate of migraine headache activity. METHODS: On 89 patients with migraine headache (74 women and 15 men), we correlated self-ratings and significant-other-ratings of patients' negative emotion with patients' report of migraine frequency and severity, which were assessed both cross-sectionally and prospectively, 3 months later. RESULTS: Other-reported negative emotion correlated with migraine activity better than did self-reported negative emotion, both cross-sectionally and prospectively. Patterns were different for women and men, however. Among women, other-reported negative emotion was positively associated with migraine activity. Among men, other-reported negative emotion was inversely associated with migraine frequency and severity. CONCLUSION: The results suggest that it may be valuable to obtain significant-other-ratings when assessing negative emotion in patients and that the genders may differ in how others' ratings are related to the patients' health.

School performance, race, and other correlates of sleep-disordered breathing in children.

OBJECTIVES: Childhood sleep-disordered breathing (SDB) has been associated with poor school performance. Both problems are common among African-American (AA) children, but potential confounders such as low socioeconomic status (SES) and obesity have not been well studied. METHODS: Children in second and fifth grades at six urban elementary schools were evaluated by teachers' ratings and year-end reading and math assessments. Risk for SDB was assessed with the validated parental Pediatric Sleep Questionnaire, and SES by qualification for school lunch assistance. RESULTS: Among 146 children whose parents completed surveys, risk for SDB was associated with AA race, low SES, and poor teacher ratings (P<0.01), but not assessment scores (P>0.1). In multiple regression models, poor school performance was consistently and independently predicted by low SES (P<0.01) but not by AA race or SDB risk. Risk for SDB was associated with low SES before, but not after body mass index (BMI) was taken into account. CONCLUSIONS: The SDB symptoms, AA race, and low SES all vary to some extent with poor school performance, but the only consistent and independent covariate of performance is SES. Risk for SDB is associated with low SES, perhaps because of a third variable, namely high BMI.