The pulse: transient fMRI signal increases in subcortical arousal systems during transitions in attention.

Studies of attention emphasize cortical circuits for salience monitoring and top-down control. However, subcortical arousal systems have a major influence on dynamic cortical state. We hypothesize that task-related increases in attention begin with a "pulse" in subcortical arousal and cortical attention networks, which are reflected indirectly through transient fMRI signals. We conducted general linear model and model-free analyses of fMRI data from two cohorts and tasks with mixed block and event-related design. 46 adolescent subjects at our center and 362 normal adults from the Human Connectome Project participated. We identified a core shared network of transient fMRI increases in subcortical arousal and cortical salience/attention networks across cohorts and tasks. Specifically, we observed a transient pulse of fMRI increases both at task block onset and with individual task events in subcortical arousal areas including midbrain tegmentum, thalamus, nucleus basalis and striatum; cortical-subcortical salience network regions including the anterior insula/claustrum and anterior cingulate cortex/supplementary motor area; in dorsal attention network regions including dorsolateral frontal cortex and inferior parietal lobule; as well as in motor regions including cerebellum, and left hemisphere hand primary motor cortex. The transient pulse of fMRI increases in subcortical and cortical arousal and attention networks was consistent across tasks and study populations, whereas sustained activity in these same networks was more variable. The function of the transient pulse in these networks is unknown. However, given its anatomical distribution, it could participate in a neuromodulatory surge of activity in multiple parallel neurotransmitter systems facilitating dynamic changes in conscious attention.

Clinical uses of cannabis and cannabinoids in the United States.

The role of cannabis in medicine is rapidly evolving. Medical cannabis is now legal in a majority of states, and THC and CBD, the prominent cannabinoids found in cannabis, have both been utilized in the development of FDA-approved drugs. Due to the complicated legal status of cannabis and cannabinoids, as well as regulations that vary from state to state, the appropriate use of these substances for both patients as well as clinicians is often unclear. Advancements in the understanding of the pharmacology of cannabis have led to numerous proposed uses of these drugs, including as antidepressant or analgesic agents. However, clinical trial data for these substances suggests that many purported indications of cannabis and cannabinoids are not supported by good clinical data. Furthermore, cannabis and several cannabinoid-based medications have potentially concerning side effect profiles that may limit their use in certain patient populations. As the legal status and clinical database of these medications continue to evolve, physicians will need to continue to balance the real potential of these compounds with their limitations and adverse effects.

Trends and factors affecting the US adult hematology workforce: a mixed methods study.

The current demand for adult hematologists in the United States is projected to exceed the existing supply. However, no national study has systematically evaluated factors affecting the adult hematology workforce. In collaboration with the American Society of Hematology (ASH), we performed a mixed methods study consisting of surveys from the annual ASH In-Service Exam for adult hematology/oncology fellows from 2010 to 2016 (8789 participants); interviews with graduating or recently graduated adult hematology/oncology fellows in a single training program (8 participants); and 3 separate focus groups for hematology/oncology fellowship program directors (12 participants), fellows (12 participants), and clinicians (10 participants) at the 2016 ASH annual meeting. In surveys, the majority of fellows favored careers combining hematology and oncology, with more fellows identifying oncology, rather than hematology, as their primary focus. In interviews with advanced-year fellows, mentorship emerged as the single most important career determinant, with mentorship opportunities arising serendipitously, and oncology faculty perceived as having greater availability for mentorship than hematology faculty. In focus group discussions, hematology, particularly benign hematology, was viewed as having poorer income potential, research funding, job availability, and job security than oncology. Focus group participants invariably agreed that the demand for clinical care in hematology, particularly benign hematology, exceeded the current workforce supply. Single-subspecialty fellowship training in hematology and the creation of new clinical care models were offered as potential solutions to these workforce problems. As a next step, ASH is conducting a national, longitudinal study of the adult hematology workforce to improve recruitment and retention in the field.