Mental Fatigue Reduces the Benefits of Self-Controlled Feedback on Learning a Force Production Task.

This study investigated the impact of mental fatigue and self-controlled versus yoked feedback on learning a force production task. We randomly assigned 44 non-athlete male students (Mage = 21.4, SD = 1.4 years) to four groups; (a) MF&SCF = mental fatigue & self-controlled feedback, (b) MF&Y = mental fatigue & yoked, (c) NMF&SCF = no mental fatigue & self-controlled feedback, and (d) NMF&Y = no mental fatigue & yoked). SCF group participants were provided feedback whenever they requested it, while YK group participants received feedback according to a schedule created by their SCF counterparts. To induce mental fatigue, participants performed a Stroop color-word task for one hour. During the acquisition (practice) phase, participants were asked to produce a given percentage of their maximum force (20%) in 12 blocks of six trials. We recorded the participants' absolute error at the end of the acquisition phase, the immediate retention test, the first transfer test, and the second transfer test (after 24 hours and without any further mental fatigue). The acquisition phase data were analyzed in a 2 (feedback) × 2 (mental fatigue) × 12 (block) ANOVA with repeated measures on the last factor, while the retention and transfer data were analyzed in 2 (feedback) × 2 (mental fatigue) ANOVAs. We found that all four groups made significant progress during practice (p < .001), but there were no significant group differences during this phase (p>.05). There was a significant interaction effect of self-controlled feedback and mental fatigue at retention (p = .018) and transfer testing (p < .001). In the mental fatigue condition, participants in the self-controlled group had poorer learning compared to participants in the yoked group; but when not mentally fatigued, participants in the self-controlled group had better learning than those in the yoked group. These findings suggest that mental fatigue reduces typical advantages of self-controlled feedback in motor learning.

Effect of 4 weeks of frankincense consumption on explicit motor memory and serum BDNF in elderly men

Background/aim: Memory is a mechanism for coding, storing, and recalling information. Weak memory and learning disability are common psychological problems in the elderly. The aim of this study was to investigate the effect of 4 weeks of frankincense consumption on explicit motor memory and serum BDNF in the elderly. Materials and methods: Twenty elderly men (mean age of 60.2 ± 1.7 years) were randomly divided into two groups: experimental (n = 12) and placebo (n = 8). The first blood samples were collected 24 h before the pretest. Then both groups participated in a 4-week exercise program based on the protocol of exercising motor memory. During this period, the experimental group received 500-mg frankincense pills two times a day. The second blood sample collection and acquisition test were conducted following the last session of the exercise program. A retention test and a third blood sampling were performed 2 weeks after the last training session. Mixed analysis of variance (2 × 3) for repeated measures was used to analyze the data. Results: Intergroup comparisons showed that frankincense had a significant effect on the acquisition and retention of explicit motor memory. No difference was observed in serum BDNF between the experimental and placebo groups. Conclusion: This study revealed that 4 weeks of frankincense consumption facilitates the acquisition and retention of motor memory in older men with moderate mental status.