Explore the vast range of titles available.

The basolateral amygdala (BLA) complex receives dense cholinergic projections from the nucleus basalis of Meynert (NBM) and the horizontal limb of the diagonal band of Broca (HDB). The present experiments examined whether these projections regulate the formation, extinction, and renewal of fear memories. This was achieved by employing a Pavlovian fear conditioning protocol and optogenetics in transgenic rats. Silencing NBM projections during fear conditioning weakened the fear memory produced by that conditioning and abolished its renewal after extinction. By contrast, silencing HDB projections during fear conditioning had no effect. Silencing NBM or HDB projections during extinction enhanced the loss of fear produced by extinction, but only HDB silencing prevented renewal. Next, we found that systemic blockade of nicotinic acetylcholine receptors during fear conditioning mimicked the effects produced by silencing NBM projections during fear conditioning. However, this blockade had no effect when given during extinction. These findings indicate that basal forebrain cholinergic signaling in the BLA plays a critical role in fear regulation by promoting strength and durability of fear memories. We concluded that cholinergic compounds may improve treatments for post-traumatic stress disorder by durably stripping fear memories from their fear-eliciting capacity.

To reduce such ignitions, electrical grid power shutoffs are used during windy weather.36 However, this approach can disrupt local economics (e.g., agriculture and healthcare) and livelihoods, with disproportionately high impacts on rural and overburdened communities.37 Wildfire smoke can be transported thousands of miles, causing significant environmental, public health, and socioeconomic impacts across the country (KMs 14.1,19.1, 25.1).38 39 Smoke from burning vegetation and built structures contains fine particulate matter (PM25), ozone precursors, and other toxic components (KM 14.2).40 Although the annual average level of PM25 has declined over recent decades due to air quality policies, the frequency and severity of smoke events in the western US make wildfire the largest contributor to PM2 5 in this region, offsetting some of those improvements (KM 14.1). Exposure to wildfire smoke is associated with adverse cardiovascular and respiratory outcomes (KM 15.1), as well as increased risks of COVID-19 mortality (Focus on COVID-19 and Climate Change).4142 Wildfire smoke may also affect neonatal human health, such as lower birthweights or pregnancy loss.43 44 Projected changes in wildfire are expected to result in a significant health burden, especially for at-risk populations.45 Susceptibility to wildfire smoke exposure can be exacerbated by age, preexisting health conditions, socioeconomic status, occupation, and housing status (e.g., people who are unhoused experience constant exposure). Efforts to strategically reduce the number of human-caused ignitions and investments in home hardening are important adaptation measures in some areas.720 Fireproofing structures and other design and construction efforts can reduce the likelihood of structure ignition, lessening wildfire risk to communities.48 Land and community planning practices-including zoning, ordinances, and building codes-influence wildfire risks to homes in wildfire-prone regions.49 Additional measures for protecting communities involve improvements in data access and usability, emergency response planning, healthcare system preparedness, and early-warning systems for evacuation and timely communication of health impacts to the public, especially for at-risk populations and outdoor workers (KMs 14.1,19.3). Traceable Accounts Description of Evidence Base and Research Gaps This focus box examines observed and projected wildfire trends for western North America and the impacts of wildfire nationally.3'38'50 This includes research that has used remotely sensed and modeled data, alongside field-based experimental and observational data, to demonstrate that the influence of climate change on current and future wildfire is through warming temperatures, which have reduced fuel moisture content and made the fuels more flammable.111214'22 Research demonstrates that roughly half of the increase in area burned is due to increases in fuel flammability as a result of anthropogenic climate change (KMs 3.5, 7.1).12 Warming, lowered humidity, and atmospheric drying (i.e., higher vapor pressure deficit) have facilitated increases in the frequency of fire-conducive weather as well as of annual area burned and the proportion burned at high severity by wildfire (KM 2.2).1416 Similar methods have also been used to elucidate factors influencing wildfire smoke pollutant mixture and the effects on human health.38'39 42 There is strong and building evidence that reducing forest fuels and lowering the density of trees in forests lessens the impact of climate-mediated stress and disturbance.4 Greater resistance and resilience to wildfire can be achieved through mechanical vegetation treatments with the use of prescribed fire and managed wildfire (KMs 7.3, 28.5).