Lesson 3 - The Brain

• The Central Nervous System consists of the brain and the spinal cord
• The Central Nervous System communicates with the rest of the body via the Peripheral Nervous System
• The Peripheral Nervous System is composed of bundles of axons between the spinal cord and the rest of the body
• The Somatic Nervous System is made up of the peripheral nerves that communicate with the skin and muscles
• The Autonomic Nervous System controls the involuntary actions of the heart, stomach, and other organs.
• The hemispheres of the brain communicate with each other through a thick bundle of axons crossing between them, called the corpus callosum
• cerebral cortex - outer covering of the forebrain
• The occipital lobe is at the rear of the head, and contains many specialized areas for interpreting visual sensory information
• The parietal lobe is directly in front of the occipital lobe
• Parietal lobe contains the primary somatosensory cortex, the area of the brain that is specialized for body senses and awareness of the location of body parts
• The temporal lobes are located on the sides of the head, near the ears
• The left temporal lobe contains important areas for language processing and comprehension
• The hypothalamus helps to regulate emotional and motivated behavior
• Other structures that lie under or near the temporal lobe include the hypothalamus, amygdala, and hippocampus
• The amygdala, an almond-shaped structure that is crucial for emotional processing, is deep inside the temporal lobes
• The hippocampus is a vital structure for memory processing
• The frontal lobes are at the front of the brain
• Frontal lobe contain the primary motor cortex, and area that is important for control of fine movements
• The foremost part of the frontal lobes, the prefrontal cortex, is responsible for organization, planning of action, and aspects of memory
• The medulla, pons, and midbrain contain the reticular system (or reticular formation)
• The cerebellum is important for coordination and timing
• Cerebellum is also in charge of tasks that require shifting of attention and discrimination between stimuli
• The medulla oblongata and the pons are two important structures in the hindbrain
• axons - control breathing and heart rate
• medulla oblongata and pons - contains axons; in charge of relaying sensory information from the head and sending motor messages back to it
• Both reflex and voluntary responses are conducted through the spinal cord
• A reflex is a rapid, automatic response to a stimulus. The spinal cord is usually the origination point of these responses
• The spinal cord communicates with the body below the head by means of sensory and motor neurons
• The sensory neurons carry information received by the senses from the extremities of the body to the spinal cord
• The motor neurons transmit messages from the central nervous system to the muscles and glands
• autonomic nervous system - division of the peripheral nervous system that is closely associated with the spinal cord; the individual has very little control over the responses in this division, thus the name.
• The Sympathetic Nervous System is the crisis management center of the autonomic nervous system
• sympathetic nervous system - It increases heart and respiration rate and prepares the body for fight or flight
• The Parasympathetic Nervous System is in charge of long-term survival related functions, nutrition, and energy conservation
• parasympathetic nervous system - decreases heart rate, increases digestive activities and promotes processes in the body that take place during rest; it is controlled by neurons at the upper and lower levels of the spinal cord
• supply the missing items

  A) increases heart rate

  B) raises blood pressure

  C) diverts blood flow to working muscles

  D) releases sugars/fats into bloodstream

  E) inhibits digestion

  F) reduces appetite

  G) dilates pupils

  H) slows down heart rate

  I) decreases blood pressure

  J) dilates blood vessels

  K) promotes energy storage

  L) stimulates digestion

  M) increases appetite

  N) constricts pupils

  
• The Endocrine System is under the control of the Nervous System; system of glands that release hormones into the bloodstream
• Hormones are chemicals that affect mood, behavior, and even anatomy
• Some neurotransmitters act as hormones when released into the bloodstream

  An example of one of these is Epinephrine, which is also called Adrenalin when it is acting as a hormone
• hypothalamus - brain region controlling the pituitary gland