Brain&Nervous System

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Nervous System: Nervous system is messages relayed by nerves. Nerves collect information from stimulus and relay messages to the brain where it can be interpreted and used. A neuron receives a message, if it is important enough, the stimulus will fire. The neuron will not fire if the message is not important enough. Depending on the severity or importance of the message, it can be fired faster or slower, but always with the same strength. these messages go to nerve fibers where they turn to electric signals and hit the next neuron via synapses'. Receptors receive these messages, which are sent to the brain, interpreted then sent to effectors to make a judgement based on the receptors findings.

SNS (Somatic Nervous System) is the term used to describe the part of our nervous system responsible for voluntary actions. This includes walking, talking, typing, typing and typing...

ANS (Autonomic Nervous System) is the term used to to describe the part of our nervous system responsible for invountary actions.

This includes heartrate, sweating, digesting etc. This system is broken down further to two parts, sympathetic and parasympathetic. Sypathetic prepares the body for emergencies and adjusts our functions to accomate our activities. Our parasympathetic fixes the damage done by the sympathetic, reducing heart rate, reducing temperature, steadying breathing etc.

Our actual physical system can be broken down into two parts. The first is the CNS (central nervous system), this is composed of our brain and spinal cord. The second part is PNS (peripheral nervous system) which is a compilation of nerves stretching out all through the body. The PNS is used to gather information then send it to the CNS. That is called input. Then the CNS interprets it, allows us to make our decision, then is send back to PNS. That is called central processing. The PNS then relays the signal to the part of the body responsible to take care of the situation and the appendage acts on that doing whatever is needed. That is output.

Brain: The brain is a large ganglion, composed of billions of neurones. It is composed of three parts: Hindbrain, midbrain and the forebrain. There are breakdowns of these parts as well. These parts are also split in half forming to hemispheres of brain. The hindbrain is located at the rear base of the skull.

Located in the hindbrain are the medulla and the pons. The medulla controls activities such as breathing, heartbeat, blinking and other repetitive tasks we rarely or never control using our somatic nervous system. The pons is more concerned with balancing, hearing, or other functions that are along those lines. The cerebellum, also part of our hindbrain, is used for posture and balance. The occipital lobe, for interpreting vision, is also located in the hindbrain.

In our midbrain, we basically relay messages. We relay from one hemisphere to another, we relay upwards and even, using the RAS, warns the brain of incoming messages. We also hold in here our somatocensory cortex, which has our body sensations.

The forebrain has thalamus, used to integrate sensory input and the hypothalamus, which controls emotions, sleep and other bodily processes. In our forebrain, as well, is the cerebral cortex. Much like a peach and its core, the cerebrum is surrounded by the half-inch thick cortex that controls our conscious thinking processes. The cerebrum inside learns, reads, understands, stores info and basically anything human and some things that animals do as well. As well, there is our motor cortex, which controls movement.