The motor system of the brain is responsible for producing and controlling motion. The generated movement is transmitted from the brain to the motor neurons of the body through nerves, thus controlling the muscles. Corticospinal tract transmits motion information from brain and spinal cord to trunk and limbs. Brain-god transmits action information to eyes, mouth and facial areas.
Large-scale sports (such as sports and arm and leg movements) occur in the motor cortex, which is divided into three parts: the primary motor cortex of the prefrontal gyrus, which is responsible for the movement of different body parts. These movements are supported and regulated by two other areas located in front of the main motor cortex: the anterior motor area and the auxiliary motor area. In the motor cortex, the area of hands and mouth is larger than that of other body parts, which makes it possible to perform finer movements. Cerebellum and basal ganglia play a role in fine, complex and coordinated muscle movements. The connection between cortex and basal ganglia controls muscle tension, posture and motor initiation, which is called extrapyramidal system? [3]。
feel
Sensory nervous system involves the reception and processing of sensory information. This information is transmitted to the brain through the reception of specific sensory organs (vision, smell, hearing and taste).
The brain receives information about touch, pressure, pain, vibration and temperature from the skin. Information about the joint position is received from the joint. Sensory cortex is located near motor cortex. Like the motor cortex, it also has regions corresponding to different body parts. Sensory information collected by sensory receptors on the skin is converted into neural signals and transmitted to the brain through a bundle of neurons in the spinal cord. Neurons extend upward from the back of the spinal cord to the back of the medulla oblongata, where they connect with "secondary" neurons. Then, these neurons move upward, connect with the "tertiary" neurons in the thalamus and enter the sensory cortex. The spinal cord conveys information about pain, temperature and total tactile sensation. Neurons travel on the spinal cord, contact with the second-order neurons in the reticular structure of the brain stem, feel pain and temperature, and also touch the peritoneal complex of the medulla oblongata.
Vision is first stimulated by external light from the retina, accepted by cone cells and rod cells and converted into nerve signals, and finally sent to the visual cortex of occipital lobe. The vision of the left visual field falls on the right side of the retina (and vice versa) and is transmitted to the lateral geniculate body through the optic nerve, thus projecting all the information on one side of the visual field to the opposite cerebral visual cortex.
Hearing and balance are produced in the inner ear. The sense of balance is produced by the fluid movement in the inner ear, and the transmission vibration produced by the small bone is responsible for transmitting sound information. They generate neural signals through vestibulocochlear nerves. The nerve signal passes through the cochlear nucleus, the olivary nucleus of the upper pole, the medial geniculate nucleus and finally reaches the auditory cortex.
The sense of smell is produced by receptor cells in the olfactory mucosa epithelium in the nasal cavity. This information reaches the olfactory nerve through the relatively permeable part of the skull. This nerve transmits information to the olfactory cortex. It is worth mentioning that among all sensory information, only olfactory information is directly transmitted to the cerebral cortex without passing through the nucleus on the thalamus.
Taste is produced by receptors on the tongue and introduced into the brain stem along the facial and throat nerves. Some sensory information in the oral cavity is also introduced into this area from the pharynx through the vagus nerve. And then transmit the information from here through the thalamus to the taste cortex? [4]。
language
Although it is traditionally believed that language functions are located in Wernicke and Bullokar, it is generally believed that a wider cortical Broca contributes to the use of language. How the brain represents, processes and acquires language is a problem being studied in the fields of psychology and neuroscience.
mood
It is still controversial to try to connect some basic emotions such as emotions in some brain regions, and some studies have not found a specific position corresponding to emotions. The amygdala, orbitofrontal cortex, insula and lateral prefrontal cortex seem to be related to emotional processing.
Executive function
Executive function is the general name of a group of cognitive processes needed to allow cognitive control behavior: it is responsible for selecting and successfully monitoring behaviors that promote the realization of selected goals. Executive function filters useless information and reduces stimuli unrelated to inhibition through attentional control and cognitive inhibition, processes and manipulates information stored in working memory, thinks about multiple concepts at the same time, switches tasks with cognitive flexibility, and inhibits impulsive behavior. [98]
The prefrontal cortex plays an important role in regulating executive function. Neuroimaging studies show that the cortical maturation of prefrontal cortex is related to children's executive function when performing cognitive control tasks such as stroop tasks. Planning ability involves dorsolateral prefrontal cortex (DLPFC), anterior cingulate cortex, right prefrontal cortex and superior marginal gyrus. Working memory operation involves dorsolateral prefrontal cortex, inferior frontal gyrus and parietal cortex.