There are three main types of volcano-composite or strato, shield and dome. Composite Volcanoes. Composite volcanoes, sometimes known as strato volcanoes, are steep sided cones formed from layers of ash and [lava] flows. The eruptions from these volcanoes may be a pyroclastic flow rather than a flow of lava.
A vagal episode or vasovagal response or vasovagal attack (also called neurocardiogenic syncope) is a malaise mediated by the vagus nerve. When it leads to fainting, also known as a syncope, it is called a vasovagal syncope, which is the most common type of fainting.
HIV can cause changes in the brain that increase the risk of behavior changes. Yawning excessively may also occur in the presence of a heart defect or disease. The vagus nerve acting on blood vessels can stimulate excessive yawning. This is called a vasovagal reaction and may be an indicator that you have a heart problem.