Exercise has emerged as an intervention that may mitigate age-related resting state functional connectivity and sensorimotor decline. Here, 42 healthy older adults rested or completed 3 sets of high-intensity interval exercise for a total of 23 min, then immediately practiced an implicit motor task with their non-dominant hand across five separate sessions. Participants completed resting state functional MRI before the first and after the fifth day of practice; they also returned 24-h and 35-days later to assess short- and long-term retention. Independent component analysis of resting state functional MRI revealed increased connectivity in the frontoparietal, the dorsal attentional, and cerebellar networks in the exercise group relative to the rest group. Seed-based analysis showed strengthened connectivity between the limbic system and right cerebellum, and between the right cerebellum and bilateral middle temporal gyri in the exercise group. There was no motor learning advantage for the exercise group. Our data suggest that exercise paired with an implicit motor learning task in older adults can augment resting state functional connectivity without enhancing behaviour beyond that stimulated by skilled motor practice.

Introduction The use of medicinal cannabis in the paediatric age group is increasing despite the lack of evidence for its efficacy or safety. Objective To map the available evidence on the efficacy and safety of medicinal cannabis in children and adolescents. Methods We conducted a scoping review and searched six electronic databases and grey literature. A study was eligible for inclusion when it investigated the efficacy or safety of medicinal cannabis for any condition, more than half of the participants were 0 to 18 years old, and had any study design except single case reports. Results We included 36 studies in our final analysis, 32 of which investigated the efficacy or safety of cannabis in treatment-resistant epilepsy. The remaining 4 studies examined patients with cancer, dysautonomia, Epidermolysis Bullosa, and motor disorders. Conclusions There is a lack of evidence on the efficacy and safety of medicinal cannabis in most paediatric conditions.

Introduction: Acute exercise can modulate the excitability of the nonexercised upper limb representation in the primary motor cortex (M1). Measures of M1 excitability using transcranial magnetic stimulation (TMS) are modulated after various forms of acute exercise in young adults, including high-intensity interval training (HIIT). However, the impact of HIIT on M1 excitability in older adults is currently unknown. Therefore, the purpose of the current study was to investigate the effects of lower limb cycling HIIT on bilateral upper limb M1 excitability in older adults. Methods: We assessed the impact of acute lower limb HIIT or rest on bilateral corticospinal excitability, intracortical inhibition and facilitation, and interhemispheric inhibition of the nonexercised upper limb muscle in healthy older adults (mean age 66 ± 8 yr). We used single and pairedpulse TMS to assess motor evoked potentials, short-interval intracortical inhibition, intracortical facilitation, and the ipsilateral silent period. Two groups of healthy older adults completed either HIIT exercise or seated rest for 23 min, with TMS measures performed before (T0), immediately after (T1), and 30 min after (T2) HIIT/rest. Results: Motor evoked potentials were significantly increased after HIIT exercise at T2 compared with T0 in the dominant upper limb. Contrary to our hypothesis, we did not find any significant change in short-interval intracortical inhibition, intracortical facilitation, or ipsilateral silent period after HIIT. Conclusions: Our findings demonstrate that corticospinal excitability of the nonexercised upper limb is increased after HIIT in healthy older adults. Our results indicate that acute HIIT exercise impacts corticospinal excitability in older adults, without affecting intracortical or interhemispheric circuitry. These findings have implications for the development of exercise strategies to potentiate neuroplasticity in healthy older and clinical populations.

Older adults show both age-related decreases in resting state functional connectivity and diminished sensorimotor function. Exercise has emerged as an intervention that may mitigate or even reverse these age-related declines. Here we sought to understand whether exercise impacts resting state functional connectivity, and motor acquisition and learning in older adults. Forty-two healthy older adults rested or completed 3 sets of high-intensity interval exercise (3 minutes at 75% maximal power output and 3 minutes light intensity) for a total of 23 minutes, then immediately practiced a complex, implicit motor task with their non-dominant hand across five separate sessions. Participants completed resting stage functional MRI before the first and after the fifth day of practice; they also returned 24-hours and 35-days following their fifth day of practice to complete short- and long-term retention tests to assess motor learning. Independent component analysis of resting state functional MRI revealed increased connectivity in the frontoparietal, the dorsal attentional, and cerebellar networks in the exercise group relative to the rest group. Seed-based analysis showed strengthened connectivity between the limbic system and right cerebellum, and between the right cerebellum and bilateral middle temporal gyri. There was no motor learning advantage for the exercise group; both rest and exercise groups demonstrated motor learning as measured at the short- and long-term retention tests. Our data suggest that exercise paired with a challenging implicit motor learning task in older adults can augment resting state functional connectivity without enhancing behaviour beyond that stimulated by skilled motor practice.