All articles tagged with #optogenetics
Stanford neuroscientist Karl Deisseroth leads the Human Neural Circuitry program, using millisecond-precision brain recordings and optogenetics to link neural activity with emotions and to develop treatments targeted at specific neural circuits for neuropsychiatric conditions.
Nagoya University researchers show orexin neurons are a necessary gate for sustained, goal-directed effort: their activity scales with the required effort, suppression lowers motivation, and boosting activity beyond natural levels does not increase motivation. Using a novel orexin-Cre rat model, chemogenetics raised breakpoints on progressive-ratio tasks while fiber photometry showed anticipation-linked orexin activity that intensifies with effort; optogenetic inhibition reduced motivation, but excitation beyond baseline did not boost it. The findings illuminate how reward prediction drives action and suggest targets for motivational deficits in mental illness, with future work on the surrounding circuitry.
University of Tokyo researchers identify a hippocampus–amygdala circuit that binds the memory of a familiar mouse to fear, causing avoidance after aggressive encounters; using optogenetics they could strengthen or erase this aversion, with the nucleus accumbens helping translate memory and fear into avoidance. While demonstrated in mice, the findings offer clues about how social memory and negative emotions interact, with potential relevance for anxiety and depression in humans.
HD mice exhibit reduced activity in VIP inhibitory neurons and corticostriatal neurons in the motor cortex, correlating with motor deficits. Optogenetic activation of VIP interneurons normalizes their activity and rescues downstream corticostriatal neuron function, producing lasting improvements in movement that persist for days, suggesting cortical inhibition modulation as a potential therapeutic strategy for HD.
A Neurobiology of Disease study finds that aging-related memory decline may be driven by an excess of inhibitory synapses in the prefrontal cortex. In aged mice, researchers identified two groups—cognitively susceptible and resilient—with the susceptible group showing higher levels of inhibitory markers (Gephyrin, VGAT) and denser inhibitory synapses in the prefrontal cortex. Using optogenetics, activating inhibitory neurons in young mice reproduced memory and exploration deficits, while similar stimulation in aged impaired mice had no additional effect, suggesting a chronic, structure‑level inhibitory load contributes to cognitive decline. The study warns that treatments increasing inhibition could worsen age-related cognitive deficits and notes limitations, including all-male subjects and the artificial nature of the manipulation.
A Nagoya City University study shows slow, spontaneous fluctuations in histamine neurons bias moment-to-moment memory accessibility in mice: higher histamine activity before a cue improves memory-guided responses, while lower activity reduces them. Using real-time cues and optogenetics, researchers confirm a priming-state mechanism that prepares memory circuits, with the basolateral amygdala acting downstream, suggesting memory lapses can arise from brain state rather than memory decay.
A new mouse study links serotonin to tinnitus by triggering a dedicated brain circuit that connects to the auditory system; increasing serotonin worsens tinnitus-like behaviors, while silencing that circuit reduces them, suggesting future treatments could separate mood benefits from tinnitus side effects caused by serotonin-boosting drugs like SSRIs.
New research shows dragonflies see red light at around 720 nm—beyond human vision—via a red opsin, a trait evolved in parallel with humans. This deeper red sensitivity could let optogenetic tools reach deeper tissues noninvasively, potentially aiding neurological research and therapies; male dragonflies may use red cues to tell sexes in flight.
A small, wireless implant uses LED light and genetic modification to communicate directly with the brain's neurons in mice, enabling new ways to study and potentially treat neurological conditions without invasive procedures or external wires.
Researchers discovered unique blue cryorhodopsins in cold-environment microbes that can sense UV light and control cellular activity, offering potential for advanced optogenetic tools and insights into microbial adaptation to UV exposure in icy habitats.
A rat study suggests that stimulating the brain region involved in sound and emotion processing, the inferior colliculus, may help alleviate motor symptoms of Parkinson's disease without affecting emotional responses, potentially opening new avenues for treatment beyond traditional basal ganglia targets.
Researchers have discovered that progesterone-responsive neurons in the anterior ventromedial hypothalamus (VMH) of female mice toggle between sexual receptivity and rejection based on fertility. These neurons are active during rejection behaviors outside the fertile phase and receive inhibitory signals during fertility, reducing their activity and allowing mating. Using optogenetics, the study confirmed these neurons act as a neural switch for rejection, offering insights into human sexual behavior and related disorders.
Researchers at UC Davis have identified distinct neural circuits responsible for the anti-anxiety effects of psychedelics, separate from those causing hallucinations. Using the psychedelic DOI in mice, they found that anxiety reduction persists after hallucinatory effects fade. By mapping and reactivating specific neurons in the prefrontal cortex, they demonstrated potential for developing psychedelics-based treatments that alleviate anxiety without inducing hallucinations. This study highlights the complexity of psychedelic effects, involving both direct and downstream neural networks.
Researchers at Tohoku University have discovered that astrocytes, cells surrounding neurons, play a crucial role in determining which memories are retained or forgotten. By using optogenetics to manipulate astrocytes in mice, they found that acidifying these cells after a traumatic event leads to memory loss, while alkalinizing them preserves memories long-term. This finding challenges the traditional view that short- and long-term memories form sequentially, suggesting they may develop in parallel. The study could inform new treatments for PTSD by targeting astrocyte functions.
Researchers at OIST and Keio University have discovered that stimulating the brain's dorsal raphe nucleus (DRN), the main source of serotonin, activates areas responsible for behavior and motivation in awake mice. Using opto-functional MRI, they observed that DRN serotonin activation stimulates the cerebral cortex and basal ganglia, providing insights into serotonin's role in mood regulation and cognitive functions. This study could advance understanding of mood disorders and behavioral adaptations.