Brain and Nervous System - AP Psychology

The limbic system is composed of the septum, cingulate gyrus, hypothalamus, and amygdala, plus other more minor formations. This system is particularly associated with the formation of memory.

The "hippocampus," part of the brain's limbic system, plays an important role in the consolidation of information from short-term memory to long-term memory. In addition, the hippocampus helps with our spatial navigation.

An MRI is a brain imaging modality that relies on magnetic fields. Strong magnets redirect the electrons within the body to produce an image. MRIs provide useful imaging of the soft tissue structures of the brain, and can be key in finding tumors, bleeding, and other brain abnormalities.

Acetylcholine is located at the neuromuscular junction, and it triggers muscle contraction in the body's cells. This neurotransmitter is most frequently found in neuronal cells in the central nervous system (CNS) and peripheral nervous system (PNS).

Varolio, a 16th-century anatomist and lecturer, was likely the first anatomist to study the brain from the bottom upwards, instead of the traditional top-down approach used by anatomists until that time. He also correctly theorized the pons as being vital in communication between the brain and spinal cord.

The limbic system is primarily located in the forebrain. Key structures of the limbic system include the hypothalamus (which moderates biological needs, such as hunger), hippocampus (which stores long-term memory), and the amygdala (which plays a role in emotional associations). The primary purposes of the limbic system are to store memories, moderate survival behaviors, and generate emotional responses. It plays a key role in biological motivations by determining such responses as hunger, sex drive, and fear.

The medulla oblongata is located in the hindbrain and brain stem. Its key purpose is to facilitate functions of the autonomic nervous system, initiating such things as respiration, heart beat, and blood pressure. It is not considered part of the limbic system.

The temporal lobe is one of the four major lobes of the brain, located on the sides of the brain behind the temples and ears. This lobe of the cerebrum houses the auditory cortex, which processes sound.

Vision is processed in the occipital lobe, located in the back of the brain. Balance is maintained by a variety of sensorimotor systems in the vestibular system, located in the inner ear. Smell is processed in the olfactory bulb, which is located in the frontal cortex of the brain.

The ventromedial hypothalamus controls feelings of hunger.

The thalamus relays sensory and motor signals to the cerebral cortex and regulates conciousness, sleep, and alertness. The frontal lobe carries out higher mental processes such as thinking, decision-making, and planning. The brain stem is the part of the brain that is connected to the spinal cord and controls the flow of messages between the brain and the rest of the body, as well as basic body functions.

Alcohol is a depressant that suppresses the secretion of excitatory neurotransmitters like glutamate, while increasing the production of the inhibitory neurotransmitter GABA. At the same time, it increases the release of dopamine to the nucleus accumbens, creating a pleasure sensation.

The amygdala is an almond-shaped region of the inner brain, or the limbic system. It is responsible for emotional learning and emotional reactions.

The cerebellum coordinates movements that are initiated by the motor cortex in the frontal lobe. The cerebellum is commonly associated with balance and and coordination. It is located at the back of the head, below the occipital lobe.

The nervous system is divided into subsystems based on nerve locations and functionality. Neural tissue located in the brain and spinal cord comprise the central nervous system; all other nervous tissue is considered part of the peripheral nervous system.

The peripheral nervous system is further divided by functionality. Somatic nerve fibers are under voluntary control, while autonomic nerve fibers are under involuntary control. Both of these subdivisions are considered part of the peripheral nervous system (giving us our correct answer). The autonomic nervous system can be further divided into the sympathetic and parasympathetic systems. The sympathetic system is responsible for stress reactions, initiating the fight or flight response, while the parasympathetic system is responsible for resting reactions, often referred to as rest and digest.

The frontal lobe is responsible for the higher-level cognitive processes associated with executive functions. It contains the primary motor cortex and is involved in decision-making, as well as many other goal-directed behaviors.

The corpus callosum is a bundle of white matter tracts that allows for communication between the two hemispheres of the cortex. The famous "split-brain" experiments involved the severing of the corpus callosum.

The purpose of an electroencephalogram (EEG) is to determine the electrical activity in the brain by the use of electrodes. These electrodes are connected to the scalp and are used to detect brain waves from the neurons of the brain. It is often used in sleep research.

Located below the thalamus, the hypothalamus controls the pituitary gland and regulates biological needs, including homeostasis (body temperature), sexual drive, aggressive behavior, and hunger.

The brain and spinal cord together make up the Central Nervous System. The Peripheral Nervous System and all of its subdivisions are composed of the various neural pathways to and from the brain/spinal cord.

The sympathetic nervous system responds to threats (for example, an angry lion walks near you) through the fight or flight mechanism. In the prior example, you could choose to battle the lion (fight) or run away from the lion (flight).

The Central Nervous System (CNS) and Peripheral Nervous System (PNS) are the two major divisions of the body's nervous system. The CNS is comprised of the brain and spinal cord, while the PNS is all the nerves outside of that. Further subdivisions of the PNS are the Somatic Nervous System (for voluntary muscle movements) and the Autonomic Nervous System (for responses to stress). The Autonomic is divided between the Sympathetic Nervous System (arouses the body under stress) and the Parasympathetic Nervous System (calms the body down after stress).