After the release of chest pressure during phase 4 of the Va

After the release of chest pressure during phase 4 of the Valsalva maneuver, was the glossopharyngeal nerve (cranial nerve IX) increasing or decreasing frequency of action potentials into the brainstem?

After the release of chest pressure during phase 4 of the Valsalva maneuver, was sympathetic innervation to the heart increasing or decreasing?

After the release of chest pressure during phase 4 of the Valsalva maneuver, was parasympathetic innervation to the heart via cranial nerve X (vagus) increasing or decreasing?

Solution

After the release of chest pressure during phase 4 of the Valsalva maneuver, the frequency of action potentials of glossopharyngeal nerve (cranial nerve IX) into the brainstem is decreased.

After the release of chest pressure during phase 4 of the Valsalva maneuver, sympathetic innervation to the heart is increased.

After the release of chest pressure during phase 4 of the Valsalva maneuver, parasympathetic innervation to the heart via cranial nerve X (vagus) is also increased.