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Spinal motoneurons contain many ion channels and receptors upon which various cannabinoids are known to act. This scoping review involved the synthesis of evidence from literature published before August 2022 about the effects of cannabinoids on quantifiable measures of motoneuron output. Four databases (MEDLINE, Embase, PsycINFO, and Web of Science CoreCollection) were queried and 4,237 unique articles were retrieved. Twenty-three studies met the inclusion criteria, and the findings from these studies were grouped according to four emergent themes: rhythmic motoneuron output, afferent feedback integration, membrane excitability, and neuromuscular junction transmission. This synthesis of evidence suggests that CB1 agonists can increase the frequency of cyclical patterns of motoneuron output (i.e., fictive locomotion). Furthermore, a majority of the evidence indicates that activating CB1 receptors at motoneuron synapses promotes excitation of motoneurons by enhancing excitatory synaptic transmission and depressing inhibitory synaptic transmission. The collated study results reveal variable effects of cannabinoids on acetylcholine release at the neuromuscular junction, and the influence of cannabinoids in this area requires more work to ensure precision of findings for CB1 agonist and antagonist impact. Altogether, these reports indicate that the endocannabinoid system is integral within the final common pathway and can impact motor output. This review contributes to understanding the effects of endocannabinoids on synaptic integration at the motoneuron and modulation of motor output. [ABSTRACT FROM AUTHOR]

The labor force of Medical Physics is one of the most gender diverse in the field of Physics, as it has attained the proportional achievement of ~30% women worldwide (Tsapaki et al. Phys Medica. 2018;55:33-39). While great strides have been made toward a gender diverse workforce, women still comprise an underrepresented group. Many strategies have been suggested to increase the participation of underrepresented persons by addressing unconscious biases, increasing opportunities, dedicated hiring policies, and providing support networks in science and medicine (Barabino et al. Sci Eng Ethics. 2019; Coe et al. Lancet. 2019), yet the personnel landscape remains largely uniform. Herein, the conditions, strategies, and approaches that facilitated gender diversity in Medical Physics are considered as a means to further the inclusion of other underrepresented groups through exemplars of mentorship, addressing unconscious biases and the implementation of inclusive practices. Furthermore, the potential for gender diversity to act as a catalyst to create an environment that is more accepting of diversity and supports and encourages inclusive practices for the participation and inclusion of other underrepresented groups in Medical Physics is discussed., (© 2020 American Association of Physicists in Medicine.)

Neuromuscular noise is a determining factor in the control of isometric force steadiness (FS), quantified as coefficient of variation (CV) of force around a preestablished target output. In this paper we examine sex-related differences of neural, muscular, and tendon influences on neuromuscular noise to understand FS in females and males. We use evidence from the literature to identify that CV of force is higher in females compared with males in the upper and lower body, with sex-related differences becoming less apparent with increasing age. Evaluation of sex-related physiology in tandem with results from FS studies indicate that differences in fibre type, contractile properties, and number of motor units (MUs) are unlikely contributors to differences in FS between females and males. MU type, behaviour of the population (inclusive of number of active MUs from the population), agonist-antagonist activity, maximal strength, and tendon mechanics are probable contributors to sexually dimorphic behaviour in FS. To clearly determine underlying causes of sex-related differences in FS, further study and reporting between females and males is required. Females and males are included in many studies; however, rich data on sexually dimorphic behaviour is lost when data are collapsed across sex or identified as nonsignificant without supporting values. This poses a challenge to identifying the underlying cause of females having higher CV of force than males. This review provides evidence of sexually dimorphic behaviour in FS and suggests that physiological differences between females and males effect neuromuscular noise, and in-turn contribute to sex-related differences in FS.