Optogenetic Manipulation of Neural Circuits for the Sleep-to-Wakefulness Transition in Mice

Secure an anesthetized mouse with an exposed skull in a stereotaxic frame.

The brain's bed nucleus of the stria terminalis (BNST) contains virally transduced neurons expressing light-sensitive cation channels.

Drill holes in the skull, insert optic fibers, and secure them with supporting screws and dental cement.

Drill additional holes to position an assembly containing electroencephalography (EEG) and electromyography (EMG) electrodes and secure it with adhesive.

Expose the neck muscles to insert the EMG electrode wires, then allow recovery.

Connect the mouse to a recording system, place it in an experimental chamber, and allow it to sleep.

Deliver light through the optic fiber to activate the light-sensitive cation channels, triggering cation influx that generates action potentials.

The signals propagate to sleep-regulatory regions and promote wakefulness.

Record the EEG signals to monitor brain activity and EMG signals to detect muscle activity to observe the sleep-to-wakefulness transition.

For electroencephalogram, or EEG, and electromyogram, or EMG, electrode implantation, first solder two stainless steel wires from which one millimeter of insulation has been stripped from both ends t