Iris dilator muscle the superior orbital fissure. From there, they travel with the nasociliary nerve and then the long ciliary nerve. They then pierce the sclera, travel between sclera and choroid to reach the iris dilator muscle. They will also pass through ciliary ganglion and travel in short ciliary nerves to reach the iris dilator muscle. The pupillary dilator acts to increase the size of the pupil to allow more light to enter the eye. It works in opposition to the pupillary constrictor. Pupil dilation occurs when there is insufficient light for the normal function of the eye, and during heightened sympathetic activity,
Muscle coactivation ground. It is also believed to be important for postural control by stabilizing the spine. Muscle coactivation is absolutely necessary for learning a fine motor skill or for any activity involving stability. In order for muscle coactivation to occur, it must inhibit reciprocal innervation, which occurs when a muscle contracts and the synergist muscle relaxes. For muscle coactivation to occur, both the muscle and synergist muscle need to contract. Muscle coactivation is measured using a technique called electromyography(EMG). This is performed by using surface EMG that responds to electrical activity of the muscle through the skin. Electrical activity is only