Those with generalized anxiety disorder are likely to have overactivation of with anxiety-provoking events: 1. Serotonin
2. The amygdala
3. The hypothalamus
4. Norepinephrine

2

Explanation:

When an individual experiences excessive and continuous worry and anxiety about certain events of life(families,job security} to the extent that this happens uncontrollably in the subject, and difficult to control, such neurological disorder is called generalized anxiety disorder (GAD).

It is caused by over activation or stimulation of the region of the brain(amygdala) that mediate response to fight and flight stimulus and fear.

It is usually diagnosed when the inability to control worries extends  beyond days to months with symptoms like poor concentrations, overthinking ,indecision, inability to relax, continuous taking every event as life threatening and disrupted sleep patterns.

Generally, sensory stimuli of fear or danger in the brain are transmitted by two brain circuits to two regions of the brain, to the peripheral cerebral cortex for processing voluntary decisions about the situation, and the Amygdala for processing involuntary emotional decision.

Physiologically; it is the amygdala that processes how the body reacts to the effects of the stimuli in the immediate environments, the influence of the stimuli on the emotions of the subject, and the involuntary response to the stimuli by the subject.

In response to the sensory stimuli of fear  It stimulates the hypothalamus, which in turn activate the circulatory and breathing centre of the brain.Therefore,hormones(adrenaline) are released into the blood stream to increase blood pressure, heartbeat, breathing rate, muscle contractions and other involuntary response to anxiety. This gives a fast response compare to the cerebral cortex which takes time to relay response.

Amygdala, generally stores memories of all emotions, fear, and anxiety. In GAD patients, their Amygdala is sensitive and had been adapted to the storage of fear and anxiety to the extent that every slight normal event which does would not portend danger  is over reacted to with  fear or flight response which triggers the two brain circuits described above to give anxiety-provoking events.

Intake of drugs, psychotherapy are the mode of treatments.

the answer is "a.) well–developed vascular system."

explanation: