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Purpose: Few studies have assessed listening effort (LE)--the cognitive resources required to perceive speech--among populations with intact hearing but reduced availability of cognitive resources. Attention/deficit/hyperactivity disorder (ADHD) is theorized to restrict attention span, possibly making speech perception in adverse conditions more challenging. This study examined the effect of ADHD on LE among adults using a behavioral dual-task paradigm (DTP). Method: Thirty-nine normal-hearing adults (aged 21-27 years) participated: 19 with ADHD (ADHD group) and 20 without ADHD (control group). Baseline group differences were measured in visual and auditory attention as well as speech perception. LE using DTP was assessed as the performance difference on a visual-motor task versus a simultaneous auditory and visual-motor task. Results: Group differences in attention were confirmed by differences in visual attention (larger reaction times between congruent and incongruent conditions) and auditory attention (lower accuracy in the presence of distractors) among the ADHD group, compared to the controls. LE was greater among the ADHD group than the control group. Nevertheless, no group differences were found in speech perception. Conclusions: LE is increased among those with ADHD. As a DTP assumes limited cognitive capacity to allocate attentional resources, LE among those with ADHD may be increased because higher level cognitive processes are more taxed in this population. Studies on LE using a DTP should take into consideration mechanisms of selective and divided attention. Among young adults who need to continuously process great volumes of auditory and visual information, much more effort may be expended by those with ADHD than those without it. As a result, those with ADHD may be more prone to fatigue and irritability, similar to those who are engaged in more outwardly demanding tasks.

Background and purpose: Whereas motor skills of the untrained upper limb (UL) can improve following practice with the other UL, it has yet to be determined if an UL motor skill can improve following practice of that skill with the lower limb (LL). Methods: Forty-five healthy subjects randomly participated in a 10-minute single-session intervention of (1) practicing 50 reaching movement (RM) sequences with the non-dominant left LL toward light switches (LL group); or (2) observing the identical 50 light switches sequences (Switches Observation (SO) group); or (3) observing nature films (Nature Observation (NO) group). RM sequence performance with the left UL toward the light switches was tested before and immediately after the intervention and retested after 24 h. Results: Reaching response time improved in the LL group more than in the SO and NO groups in the posttest (pBonferroni = 0.038 and pBonferroni < 0.001, respectively), and improved in the LL group more than in the NO group in the retest (pBonferroni = 0.004). Percentage of fails did not differ between groups across the timepoints. Conclusions: It appears that the actual practice of the RM sequence skill with the UL together with the cognitive element embedded in the observation of the RM sequences contributes to ipsilateral transfer from LL to UL. [ABSTRACT FROM AUTHOR]

Context: Decreased scapular upward rotation (UR) and diminished activation of the serratus anterior (SA) and lower trapezius (LT) are often observed among patients with subacromial impingement syndrome. Maintaining the elbow fully flexed during shoulder flexion may limit glenohumeral motion due to passive insufficiency of the triceps brachii and therefore facilitate greater scapular UR and increased scapular muscle activation. Objectives: To compare scapular UR, SA, upper trapezius (UT), middle trapezius, and LT activation levels between shoulder flexion with the elbow extended (Flexion-EE) to shoulder flexion with the elbow fully flexed (Flexion-EF). This study hypothesized that Flexion-EF would result in greater scapular UR, greater SA and LT activation, and a lower UT/SA and UT/LT activation ratio compared with Flexion-EE. Design: Cross-sectional study. Setting: A clinical biomechanics laboratory. Participants: Twenty-two healthy individuals. Main Outcome Measures: Scapular UR and electromyography signal of the SA, UT, middle trapezius, and LT, as well as UT/SA and UT/LT activation ratio were measured during Flexion-EE and Flexion-EF. Results: Flexion-EF resulted in greater scapular UR compared with Flexion-EE (P < .001). Flexion-EF resulted in greater S A activation, lower UT activation, and a lower UT/SA activation ratio compared with Flexion-EE (P< .001). Conclusions: Fully flexing the elbow during shoulder flexion leads to increased scapular UR primarily through greater activation of the SA. This exercise may be of value in circumstances involving diminished scapular UR, decreased activation of the SA, and an overly active UT such as among patients with subacromial impingement syndrome. [ABSTRACT FROM AUTHOR]

Background: Little information exists to guide the choice of exercise for regaining shoulder range of motion (ROM). The purpose of this study was to compare the maximal ROM reached, pain and difficulty associated with 4 commonly prescribed exercises. Methods: Forty (9 females) patients with various shoulder disorders and a limited flexion ROM performed 4 exercises for regaining shoulder flexion ROM in a randomized order. Exercises included the self-assisted flexion, forward bow, table slide and rope-and-pulley. Participants were videotaped while performing all exercises and the maximal flexion angle reached during each exercise was recorded using Kinovea motion analysis freeware (Kinovea 0.8.15). Pain intensity and the perceived level of difficulty associated with each exercise were also recorded. Results: The forward bow and table slide generated significantly greater ROM compared with the self-assisted flexion and rope-and-pulley (P ≤ 0.005). The self-assisted flexion was associated with a greater pain intensity compared with the table slide and rope-and-pulley (P = 0.002) and a greater perceived level of difficulty compared with the table slide (P = 0.006). Conclusions: Due to the greater ROM allowed, and similar or even lower level of pain or difficulty, clinicians may wish to initially recommend the forward bow and table slide for regaining shoulder flexion ROM. [ABSTRACT FROM AUTHOR]