Question

Generally, its true that nervous systems can be functionally divided in categories basing on sensation, response and integration. However, I just has a question in relation to this topic, when someone is dreaming, there are a times when someone wakes up tired, and sweating very much if it was a horrifying thing, therefore, which nerve serves for this response? Or its not related to anything of the body? If there is, how can the situation in such a manner be regulated?

Answer 1

Before getting to know, a brief definition for few concepts are needed to interconnect:

REM:

Rapid eye movement REM sleep is discontinuous chunked sleep of 4-5 periods which together make 20% of the slumber. During this period, there is a rapid eye movement, irregular heartbeat, increased rates of respiration and the irregular heartbeat, and increased rates of respiration during when the nightmares tend to happen if REM interval lengthens. When we awake, the memories of the dream begin to integrate and consolidate make us to to feel as we emerge from REM sleep because of the remembrance of images and events that we had in dream.

Amygdala:

Amygdala is a paired organ and a part of limbic system, a collection of cells near the base of brain. This region is responsible for emotional remembrance, correlation of events and memories attached to them and where the emotions are given meaning. It is a master to process all kinds of emotions such as fear and pleasure.

During threats or feeling of threatened, amygdala automatically activates the sympathetic nervous system SNS for the fight-or-flight response.

Frontal lobes:

Frontal lobes are in front part of the brain which is responsible for logical reasoning and processing of the emotions. Unlike autonomic response by amygdala, frontal lobe render the conscious response.

When there is a threat, amygdala rapidly activate SNS, simultaneously frontal lobe process the depth of danger. If the threat is moderate, frontal lobe override amygdala and when it is strong the reverse happens. But the nightmare cause the amygdala hijack which leads to over acting amygdala. This would results in hyper activity of SNS results in sweating and irregular heart beat after waking up from the nightmare.

A study revealed that nightmare affect the network dysfunction, which shows decreased activity of medial prefrontal cortex, and increased function of amygdala, hippocampus, and anterior cingulate cortex. These cerebral alterations account for the evaluation of the nightmare.