--Low levels of these TWO neurotransmitters are associated with severe depression. Serotonin and Norepinephrine --This neurotransmitter is involved in voluntary movement, learning, emotion, reward, and perception. Dopamine --This neurotransmitter enables involuntary muscle action and is associated with memory. Acetylcholine --This is a major excitatory neurotransmitter. Glutamate --If the brain is flooded with opiates like heroin and morphine the brain may stop producing these natural opiates (pain killers). Endorphins --The pleasure and reward aspect of addiction to drugs such as cocaine and amphetamines is due to the overstimulation of this type of neuron. Dopamine --Anti-anxiety medications stimulate this inhibitory neurotransmitter which has a calming effect. GABA --Prozac and other antidepressants increase the level of these two neurotransmitters in the brain. Serotonin and Norepinephrine --This is a major inhibitory neurotransmitter. GABA --Excess receptor activity of this neurotransmitter has been linked to schizophrenia. Dopamine --An oversupply of this neurotransmitter can over-stimulate the brain and cause migraines or seizures. Glutamate --When neurons that produce this neurotransmitter deteriorate, a person may begin experiencing symptoms of Alzheimer’s disease. Acetylcholine --When the brain is starved of this neurotransmitter, it produces tremors and decreased mobility associated with Parkinson’s disease. Dopamine --Some substances that affect the action of this neurotransmitter by impacting involuntary muscles are nicotine, Botox, curare poison, and black widow spider venom. Acetylcholine ------Subdivision of the PNS that controls voluntary activities such as the activation of skeletal muscles. Somatic --"Rest and Digest" is this subdivision's mantra. Parasympathetic Nervous System (PNS) --Subdivision of the PNS that regulates the activity of the heart and smooth muscle, and of the glands. Autonomic Nervous System -- Pupil dilation, increased heart rate and decreased digestion are all controlled by which nervous system subdivision? Sympathetic Nervous System --A major subdivision of the nervous system that interprets incoming information and issues orders. Central Nervous System (CNS) --A major subdivision of the nervous system that serves as communication lines, linking all parts of the body to the CNS. Peripheral Nervous System --If your perspiration decreases, your digestion increases and blood flow to your sex organs is allowed, this subdivision of the nervous system is doing its job. Parasympathetic Nervous System Sensory neurons are the nerve cells that are activated by sensory input from the environment Motor neurons of the spinal cord are part of the central nervous system (CNS) and connect to muscles, glands and organs throughout the body. Interneurons are the ones in between - they connect spinal motor and sensory neurons, transfer signals between sensory and motor neurons, and communicate with each other. They are multipolar, just like motor neurons. --- Our internal communication system is formed by basic building blocks: neurons, or nerve cells --- Dendrite fibers receive messages and conduct them toward the cell body, axon fibers send out messages to other neurons or to muscles or glands --- The messages neurons carry are electrical signals, or nerve impulses, called action potentials --- Neurons begin and end at the synapse; at the synapse two neurons are separated by a tiny synaptic gap --- Most signals are excitatory, others are inhibitor. Gas pedal à Brake pedal --- If the excitatory signals exceed the inhibitory signals by a minimum intensity, or threshold, the combined signals trigger an action potential. --- The neuron’s reaction is an all-or-none response. --- When the action potential reaches the axon’s end, your neural system converts an electrical impulse into a chemical message --- At the synapse, the impulse triggers the release of neurotransmitter molecules, chemical messengers that can cross the synaptic gap --- The neurotransmitters bind to receptor sites on the receiving neuron. They then act as excitatory or inhibitory signals. The excess neurotransmitters finally drift away, are broken down by enzymes, or are reabsorbed by the sending neuron—a process called reuptake. Some antidepressant medications work by partially blocking the reuptake of mood-enhancing neurotransmitters --- How does our nervous system allow us to experience the difference between a slap and a tap on the back? Stronger stimuli (the slap) cause more neurons to fire and to fire more frequently than happens with weaker stimuli (the tap) EEG: A recording of the electrical waves sweeping across the brain’s surface. An EEG is useful in studying seizures and sleep. CAT Scan (CT Scan): A series of x-ray photographs taken from different angles and combined by computer into a composite representation of a slice through the body PET: Visual display of brain activity. Allows us to see what part of the brain is active by tracing where a radioactive form of glucose goes while the brain performs a given task. MRI: Makes images from signals produced by brain tissue after magnets align the spin of atoms. The arrows below show ventricular enlargement in a schizophrenic patient (right). - Occipital lobe: This is found in the back of the brain. The area is involved with the brain's ability to recognize objects. It is responsible for our vision. Temporal lobe: The temporal lobes are found on either side of the brain and just above the ears. The temporal lobes are responsible for hearing, memory, meaning, and language. They also play a role in emotion and learning. The temporal lobes are concerned with interpreting and processing auditory stimuli. Parietal lobe: The parietal lobes are found behind the frontal lobes, above the temporal lobes, and at the top back of the brain. They are connected with the processing of nerve impulses related to the senses, such as touch, pain, taste, pressure, and temperature. They also have language functions. Frontal lobe: It is concerned with emotions, reasoning, planning, movement, and parts of speech. It is also involved in purposeful acts such as creativity, judgment, and problem solving, and planning Cerebral cortex: The cerebral cortex controls your thinking, voluntary movements, language, reasoning, and perception. In higher mammals the cortex looks like it has lots of wrinkles, grooves and bumps. Cerebellum: controls your movement, balance, posture, and coordination. New research has also linked it to thinking, novelty, and emotions. The limbic system, often referred to as the "emotional brain", is found buried within the cerebrum. Hypothalamus: controls your body temperature, emotions, hunger, thirst, appetite, digestion and sleep. The hypothalamus is composed of several different areas and is located at the base of the brain. It is only the size of a pea (about 1/300 of the total brain weight) but is responsible for some very important behaviors. Thalamus: controls your sensory integration and motor integration. Receives sensory information and relays it to the cerebral cortex. The cerebral cortex also sends information to the thalamus which then transmits this information to other parts of the brain and the brain stem. Pituitary gland: it controls your hormones, and it helps to turn food to energy. Without this gland you could eat but you wouldn't get any energy from the food. Amygdala: The amygdala (there are two of them) control your emotions such as regulating when you're happy or mad. Your amygdala is very important. Without it you could win the lottery and feel nothing. You wouldn't be happy. Hippocampus: Forms and stores your memories (scientists think there are other things unknown about the hippocampus) and is involved in learning. If you didn't have it, you wouldn't be able to remember anything. People with Alzheimer's disease loose the functioning of their hippocampus. Medulla: base of the brainstem that controls heartbeat and breathing Limbic System: A neural system below the cerebral hemispheres associated with emotions and drives. Motor Cortex: An area at the rear of the frontal lobes that controls voluntary movements Somatosensory cortex: an area at the front of the parietal lobes that registers and processes body’s touch and movement sensations Plasticity: The brain's ability to change and adapt as a result of an experience Corpus callosum: large band of neural fibers connecting the two brain hemispheres Agonist: A molecule that, by binding to a receptor site, stimulates a response PNS: the sensory and motor neurons that connect the central nervous system to the rest of the body Antagonist: inhibits or blocks a response Somatic: also called the skeletal nervous system Sympathetic nervous system: the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations. Amygdala consists of two lima bean-sized neural clusters linked to the emotions of fear and anger. The endocrine system is the body's slow chemical communication system. It consists of a set of glands that secrete hormones directly into the bloodstream. Hormones are chemical messengers mostly manufactured by the endocrine system.
