Professor Trevor Robbins describes the noradrenaline system, which is highly involved in arousal.
Transcript:
The noradrenergic system of the brain originates in brain stem structures such as the locus ceruleus, and also behind the locus ceruleus, in an area called the medulla. There are two main branches of the noradrenaline [also known as norepinephrine] system. One is called the dorsal ascending system, which projects all over the forebrain, including the neocortex and the hippocampus. One of the places it does NOT go to is the striatum. We don't know why that is.
The ventral bundle projects mainly to the hypothalamus and to other visceral parts of the brain including the limbic system, which is involved in emotion.
The noradrenaline system, globally speaking, is involved in arousal. It is least active when you're asleep, especially when you are dreaming and it is most active when you are aroused, either moving a lot or thinking a lot, when it will affect your cortical electroencephalogram [EEG]. It is really turned on by novelty. So, novelty will make this system work very fast. Too much stimulation, including too much novelty, may cause stress and that may be linked to anxiety. So, this is the way in which the noradrenaline system may go wrong as well.
The limbic system is a group of brain structures including the amygdala, hippocampus, and hypothalamus that are involved in processing and regulating emotions, memory, and sexual arousal.
Professor Trevor Robbins discusses two functions of the cholinergic (acetylcholine) system. One is involved in arousal and memory, the other in the sleep/waking cycle.
Professor Trevor Robbins explains that the dopamine system is a group of cells originating in the midbrain whose function may be to prepare the brain to think, move, and anticipate rewards.
The brain stem consists of a group of structures, including the pons, medulla oblongata, and midbrain. It controls autonomic functions such as breathing, heart rate, and blood pressure.
Serotonin is the biochemical most commonly associated with depression. Professor Wayne Drevets discusses other systems including norepinephrine, glutamate, and dopamine.