The role of the cerebellar cortex in motor learning was investigated by comparing the paramedian lobule of adult rats given difficult acrobatic training to that of rats that had been given extensive physical exercise or had been inactive. The paramedian lobule is activated during limb movements used in both acrobatic training and physical exercise. Acrobatic animals had greater numbers ofsynapses per Purkin e cell than animals from the exercise or inactive groups. No significant difference in synapse number or size between the exercised and inactive groups was found. This indicates that motor learning required of the acrobatic animals, and not repetitive use of synapses during physical exercise, generates new synapses in cerebellar cortex. In contrast, exercise animals had a greater density ,f blood vessels in the molecular layer than did either the acrobatic or inactive animals, suggesting that increased Synaptic activity elicited compensatory angiogenesis.Although many aspects of experience can alter synaptic connectivity (1-5), it has-been difficult'to relate unequivocally these changes to learning and memory because the morphological effects of leaning could not be isolated from those of behaviors. required to perform the task. For example, maze training (3) and forelimb reach-training (5) can alter neuronal morpholoy, but substantia trepetition of movements is required fo arning these, tasks'. Thus it is not possible to ascrib~e te morphological effects to learning per se.The cerebellar cortex may be particularly appropriate for testing hypotheses about synaptic plasticity because empirical evidence has implicated cerebellar cortex in motor skill learning (6,7,36), and there is some indication that synapse formation underlies cerebellar cortical learning, as suggested by dendritic-field changes in Purkinje cells of rodents and monkeys exposed to challenging. sensory-motor environments (8-10). Synaptogenesis in adult rat cerebellar cortex also occurs when afferents are cut (11,12). Furthermore, theorists have noted the suitability of cerebellar cortex for motor learning, with its convergence of two afferent systems conveying extensive somatic and cerebral state information upon the Purkinje cell, a single-output neuron that modulates motor activity (13)(14)(15)(16)(17).The results of the present study show that learning, as opposed to the motor activity necessary for learning a complex motor task, is responsible for synapse formation in the cerebellar cortex. We report a dissociation oflearning and motor activity, in which animals provided with complex visuomotor learning and minimal motor activity (acrobatic training)-form substantial numbers of new synapses in cerebellar cortex, whereas animals given extensive locomotor exercise with minimal opportunities for learning (repetitive exercise) formed new blood vessels but formed no more new synapses than animals in an inactive control group. MATERIAL AND METHODSAnimals and Training. Thirty-eight adult Long-Evans hooded female rats, kept in small groups...

This study compared the morphology of cerebellar cortex in adult female rats exposed for 1 month to repetitive exercise, motor learning, or an inactive condition. In the exercise conditions, rats that were run on a treadmill or housed with access to a running wheel had a shorter diffusion distance from blood vessels in the molecular layer of the paramedian lobule when compared to rats housed individually or rats that participated in a motor skill learning task. Rats taught complex motor skills substantially increased the volume of the molecular layer per Purkinje neuron and increased blood vessel number sufficiently to maintain the diffusion distance. These results dissociate angiogenesis associated with increased neuropil volume (as seen in the motor learning group) from angiogenesis associated with increased metabolic demands (as seen in the exercise groups). While the volume fraction of mitochondria did not differ among groups, the mitochondrial volume fraction per Purkinje cell was significantly increased in the motor skill rats. This appears to parallel the previously reported increase in synapses and associated neuropil volume change.

Objectives:The prevalence of opioid use disorder (OUD) during pregnancy is increasing. Practical recommendations will help providers treat pregnant women with OUD and reduce potentially negative health consequences for mother, fetus, and child. This article summarizes the literature review conducted using the RAND/University of California, Los Angeles Appropriateness Method project completed by the US Department of Health and Human Services Substance Abuse and Mental Health Services Administration to obtain current evidence on treatment approaches for pregnant and parenting women with OUD and their infants and children.Methods:Three separate search methods were employed to identify peer-reviewed journal articles providing evidence on treatment methods for women with OUD who are pregnant or parenting, and for their children. Identified articles were reviewed for inclusion per study guidelines and relevant information was abstracted and summarized.Results:Of the 1697 articles identified, 75 were included in the literature review. The perinatal use of medication for addiction treatment (MAT, also known as medication-assisted treatment), either methadone or buprenorphine, within comprehensive treatment is the most accepted clinical practice, as withdrawal or detoxification risks relapse and treatment dropout. Medication increases may be needed with advancing pregnancy, and are not associated with more severe neonatal abstinence syndrome (NAS). Switching medication prenatally is usually not recommended as it can destabilize opioid abstinence. Postnatally, breastfeeding is seen as beneficial for the infant for women who are maintained on a stable dose of opioid agonist medication. Less is known about ideal pain management and postpartum dosing regimens. NAS appears generally less severe following prenatal exposure to buprenorphine versus methadone. Frontline NAS medication treatments include protocol-driven methadone and morphine dosing in the context of nonpharmacological supports.Conclusions:Women with OUD can be treated with methadone or buprenorphine during pregnancy. NAS is an expected and manageable condition. Although research has substantially advanced, opportunities to guide future research to improve maternal and infant outcomes are provided.