Volume 9 Issue 12, December 2006

Exogenous cannabinoid receptor agonists impair hippocampus-dependent learning and decrease the power of hippocampal electroencephalographic activity. A new paper shows that cannabinoids desynchronize neuronal assemblies without affecting average firing rates, and that this effect correlates with memory deficits in individuals.

Microglia, the brain's intrinsic immune cells, rapidly sense brain injury and help clear cellular debris. Haynes et al. now show that P2Y₁₂ receptors are critical for activating microglia and directing them to the site of injury.

Opioids are commonly thought of as compounds that alleviate pain. A new study finds that elevated levels of the opioid dynorphin can unexpectedly activate bradykinin receptors, contributing to the maintenance of neuropathic pain.

Sensory systems are thought to use an internal copy of motor commands to determine which sensations are caused by the self versus the world. A new paper proves that an identified pathway performs this function for eye movements.