Reconstruction of great auk population dynamics suggests that hunting pressure alone could have been responsible for their extinction, demonstrating that even abundant, widespread species can be vulnerable to intense exploitation.
Prefrontal dopamine regulates inhibition of fear extinction circuits in the infralimbic cortex and disinhibition of fear expression circuits in the amygdala, leading to fear reinstatement.
Dopamine neurons in medial versus lateral VTA encode different signals during fear extinction, yet inhibition of both populations influences fear extinction, at different times.
When the fear-enhancing effects of prior exposure to stress are absent, the expression of fear reflects normal neural activity in the medial prefrontal cortex, not stress-induced hyperactivity in the amygdala.
The inhibition mechanism of fear extinction operates primarily in the early phase of extinction training, and the erasure mechanism takes over after that.
A new open-source computational toolbox for processing in vivo microendoscopic calcium imaging data performs signal demixing and denoising much more accurately than previously available methods, significantly improving the utility of this imaging modality.
Through visualization of directly-labeled RhoGTPase both in vitro and in vivo, RhoGDI is found to spatiotemporally regulate RhoGTPase activity through the extraction of active RhoGTPase.