Answer:
The main neurotransmitter is acetylcholine. From a functional point of view, this system is related to: memory and learning, motivations, perceptions, attention, regulation of organic functions, motor functions and movement, and some pathologies such as Alzheimer's.
Explanation:
Acetylcholine is the substance responsible for the transmission of nerve impulses from preganglionic to postganglionic neurons, in the ganglia of the autonomic nervous system. At the level of the parasympathetic nervous system, it also mediates the transmission between the postganglionic neuron and the effector organ. In addition, it is the mediator of nerve transmission of the terminal motor plate. The cholinergic pathways project from the Meynert basal nuclei, located in the pale, to the cortex (mainly frontal and parietal), and to the thalamus, amygdala, and hippocampus. The cholinergic receptors are divided into nicotinic and muscarinic. Nicotinic receptors bind to ion channels, are faster and generally excitatory, are blocked by curare, and are stimulated by nicotine and acetylcholine. Muscarinic receptors bind to the G protein, are slower, are excitatory or inhibitory, are blocked by atropine and stimulated by muscarin, pilocarpine, and acetylcholine. Acetylcholine is also widely distributed in the brain and is a key neurotransmitter in the regulation of vigilance levels and in the operation of large areas of association. Acetylcholine has been considered a mediator of learning and memory processes in the central nervous system. It has been linked to cognitive processes such as attention and learning. At the neuroendocrine level, acetylcholine increases vasopressin secretion by stimulating the posterior lobe of the pituitary. It also decreases the secretion of prolactin from the posterior pituitary. At the parasympathetic level, it contributes to intervening in food intake and digestion, anabolic processes and physical rest, increases blood flow to the gastrointestinal tract, gastrointestinal muscle tone and gastrointestinal endocrine secretions. The heart rate decreases. At the sensory level, the cerebral cholinergic neurons form a large ascending system whose origin is in the brain stem and innervates large areas of the cerebral cortex and is probably identical to the reticular activating system, in addition to maintaining consciousness they seem to intervene in the transmission of visual information, both in the superior colliculus and in the occipital cortex.
