Previous studies have shown that AgRP neurons in the arcuate nucleus (ARC) respond to energy deficits and play a key role in the control of feeding behavior and metabolism. Here, we demonstrate that chronic unpredictable stress, an animal model of depression, decreases spontaneous firing rates, increases firing irregularity and alters the firing properties of AgRP neurons in both male and female mice. These changes are associated with enhanced inhibitory synaptic transmission and reduced intrinsic neuronal excitability. Chemogenetic inhibition of AgRP neurons increases susceptibility to subthreshold unpredictable stress. Conversely, chemogenetic activation of AgRP neurons completely reverses anhedonic and despair behaviors induced by chronic unpredictable stress.

After tracing the origins of schizophrenia to genes expressed in the placenta while in utero, scientists have now zeroed in on the combination of risk factors that could predict which infants are at greatest risk of developing the condition later in life.

The findings reinforce an emerging picture of schizophrenia as a genetic disorder, with a fate determined by complications that can arise during pregnancy.

Researchers from the Lieber Institute for Brain Development at Johns Hopkins University and the University of North Carolina in the US analysed the relationship between key genes and cognitive development in the first few years after birth.

Although wireless optogenetic technologies enable brain circuit investigation in freely moving animals, existing devices have limited their full potential, requiring special power setups. Here, the authors report fully implantable optogenetic systems that allow intervention-free wireless charging and controls for operation in any environment.