Basics of the brain Flashcards
What is Neuroscience?
Neuroscience is the branch of biology that focuses on the body’s nervous system including the brain, attempts to shed light on the effects of drug use on the brain and how brain chemistry is changed. It provides us with an understanding of how substances affect brain structure as well as the parts of the brain that have shown the ability to repair themselves following abstinence from substance use.
True or False substance-related use is a brain-based disease.
True. The National Institute on Drug Abuse (NIDA) Neuroscience Consortium, through its research efforts, has established that substance-related use is a brain-based disease. Research findings have focused on identifying the brain mechanisms that underlie drug cravings and reward systems, vulnerabilities to severe use, and the consequences of overusing substances.
The brain itself is divided into two sections called hemispheres, what is it that connects them to each other?
The Corpus Callosum forms the fissure dividing them, and connects them with fibers. The corpus callosum serves as the communication vehicle between the left and right sides of the brain, the fibers that connect the two halves. (It adds the two parts together. Think of the corPLUS CalloSUM. Since the corpus callosum coordinates communication between the two hemispheres, think of corpus Call Someone.)
The left hemisphere controls the right side of the body and is basically concerned with thinking and intellectual functions. It is the site of logic and verbal ability, producing and understanding language. What does the right hemisphere do?
The right hemisphere controls the left side of the body and is considered to be the creative side, involving intuitive and creative processes. It is involved with temporal and spatial relationships, analysis of nonverbal information, and communicating emotion. It uses pictures, while the left hemisphere uses words.
The brain consists of three basic parts, what are they?
The hindbrain, which contains the cerebellum and lower brain stem; the midbrain, which houses relay areas from the upper brain stem; and the forebrain, which houses the mechanisms that most often interact with substances that can cross the blood–brain barrier.
The forebrain includes the cerebral hemisphere and the rind or outer covering (about 2 mm thick) called the cerebral cortex. What does the it “do”?
The cerebral cortex is responsible for activities of a higher state of consciousness including thought, perception, motor function, sensory data processing, and vision. (Imagine a Texas cowboy hat on top of a brain. The cortex is the outer layer of the brain just under the hat where complex thinking occurs)
What is the thalamus responsible for?
The thalamus regulates sleep, alertness and wakefulness. It receives information for all of the senses EXCEPT for smell. The thalamus takes sensations that come from the body and directs them to the appropriate part of the brain for processing. (Think of Hal and Amos – two traffic cops in the brain who direct these sensations to the right route).
The brain is composed of how many neurons?
The brain is composed of an estimated 100 BILLION neurons with an astounding range of structural variations and functional diversity found in brain cells that in complex ways are important to cognition, behavior, and psychopathology.
What is neurogenesis?
Neurogenesis is the study of the regrowth of cells. Evidence suggests that the neuroplasticity of the brain does allow for neuron growth and development after damage. Although previously thought to be stable, adult brains continue to produce neurons in specific areas throughout life and are even able to regrow after damage.
Neurotransmitter interactions function for the well-being of the individual, ensuring the basic survival of that organism. Explain the role of neurotransmitters.
They are chemical messengers (molecules) released by electrical impulses (action potentials) that reach the presynaptic membrane of a given synapse. These pathways can send thousands of electrochemical messages per second and yet work in harmony.
List the 7 main neurotransmitters involved in substance use.
acetylcholine (Ach), dopamine (DA), norepinephrine (NE), epinephrine (E), serotonin (5-HT), histamine (H), and gamma-aminobutyric acid (GABA).
Dopamine-containing neurons relay pleasure messages through WHAT part of the brain via a circuit that spans the brain stem, the limbic system, and the cerebral cortex.
The nucleus accumbens (also known as the nucleus accumbens septi, latin for nucleus adjacent to the septum) is a major component of of the brains “reward circuit”. Dopamine release in the NA is so consistently tied with pleasure that neuroscientists refer to the region as the “Brain’s pleasure center”. ALL drugs of abuse cause a powerful surge of dopamine to the NA.
List the substance classification systems
Depressants, stimulants, cannabis, cannabicyclohexanol/Spice/K2, hallucinogens, club drugs, volatile substances/inhalants, and anabolic steroids.
The blood–brain barrier is not completely developed in humans until age 1 to 2 and can be damaged by head trauma or cerebral infection. What is its function?
The blood–brain barrier acts to keep certain substances in the blood away from brain cells. Substances are considered psychoactive when they can cross the blood–brain barrier and create changes in the brain and, therefore, in the thinking and behavior of the user. They accomplish this by exciting, quieting, or distorting the chemical and electrical state of the brain. Even some foods, such as sugar, act on similar neural pathways as psychoactive substances and can produce feelings of euphoria.
Define “neuroplasticity”
Plasticity refers to the brain’s ability to modify itself after some type of injury or illness. Usually the brain areas that are related to the damaged/missing part develop the ability to function as a part of the new system. For example, in blind people the visual cortex may register and process touch and/or hearing also (heightening those senses) Our brains demonstrate more plasticity when we are children.
