addiction: The National Institute of Drug Abuse defines this as a complex chronic disease that is “characterized by drug seeking and use that is compulsive, or difficult to control, despite harmful consequences.” A first exposure to drugs is usually voluntary. But repeated use of certain drugs, NIDA explains, can create changes in the brain that make it hard “to resist intense urges to take drugs.”
adolescence: A transitional stage of physical and psychological development that begins at the onset of puberty, typically between the ages of 11 and 13, and ends with adulthood.
adolescent: Someone in that transitional stage of physical and psychological development that begins at the onset of puberty, typically between the ages of 11 and 13, and ends with adulthood.
average: (in science) A term for the arithmetic mean, which is the sum of a group of numbers that is then divided by the size of the group.
behavior: The way something, often a person or other organism, acts towards others, or conducts itself.
benign: Not harmful to one’s health. Malignant, in contrast, means harmful and generally refers to cancer.
brain scan: A technique to view structures inside the brain, typically with X-rays or a magnetic resonance imaging (or MRI) machine. With MRI technology — especially the type known as functional MRI (or fMRI) — the activity of different brain regions can be viewed during an event, such as viewing pictures, computing sums or listening to music.
cell: The smallest structural and functional unit of an organism. Typically too small to see with the unaided eye, it consists of a watery fluid surrounded by a membrane or wall.
chemical: A substance formed from two or more atoms that unite (bond) in a fixed proportion and structure. For example, water is a chemical made when two hydrogen atoms bond to one oxygen atom. Its chemical formula is H2O. Chemical also can be an adjective to describe properties of materials that are the result of various reactions between different compounds.
colleague: Someone who works with another; a co-worker or team member.
cortex: The outermost part of an organ, such as the kidney or brain. Or the outer part of some microbes or plant, such as a tree’s bark or a mango’s rind.
cortical: (in neuroscience) Of or relating to the brain’s cortex.
development: (in biology) The growth of an organism from conception through adulthood, often undergoing changes in chemistry, size and sometimes even shape.
disorder: (in medicine) A condition where the body does not work appropriately, leading to what might be viewed as an illness. This term can sometimes be used interchangeably with disease.
docking: The act of bringing together and inserting one thing into another.
forest: An area of land covered mostly with trees and other woody plants.
frequency: The number of times some periodic phenomenon occurs within a specified time interval. (In physics) The number of wavelengths that occurs over a particular interval of time.
impulsive: (n. impulsivity) Quick to act; not willing to wait. Not waiting for deliberation or a weighing of consequences.
link: A connection between two people or things.
marijuana: A mind-altering drug. It is made from the leaves (and sometimes stems or seeds) of the Cannabis sativa plant. This drug also goes by the colloquial terms pot and weed.
mature: (adj.) Connoting an adult individual or full-grown and fully developed (non-juvenile) form of something. (verb) To develop toward — or into — a more complex and full-grown form of something, be it a living thing, a technology or an idea.
mental health: A term for someone’s emotional, psychological and social well-being. It refers to how people behave on their own and how they interact with others. It includes how people make choices, handle stress and manage fear or anxiety. Poor mental health can be triggered by disease or merely reflect a short-term response to life’s challenges. It can occur in people of any age, from babies to the elderly.
MRI: Short for magnetic resonance imaging. It’s an imaging technique to visualize soft, internal organs, like the brain, muscles, heart and cancerous tumors. MRI uses strong magnetic fields to record the activity of individual atoms.
pot: A slang term for marijuana.
prefrontal cortex: A region containing some of the brain’s gray matter. Located behind the forehead, it plays a role in making decisions and other complex mental activities, in emotions and in behaviors.
psychologist: A scientist or mental-health professional who studies the human mind, especially in relation to actions and behaviors.
radioactive: An adjective that describes unstable elements, such as certain forms (isotopes) of uranium and plutonium. Such elements are said to be unstable because their nucleus sheds energy that is carried away by photons and/or and often one or more subatomic particles. This emission of energy is by a process known as radioactive decay.
receptor: (in biology) A molecule in cells that serves as a docking station for another molecule. That second molecule can turn on some special activity by the cell.
reward: (In animal behavior) A stimulus, such as a tasty food pellet, that is offered to an animal or person to get them to change their behavior or to learn a task.
risk: The chance or mathematical likelihood that some bad thing might happen. For instance, exposure to radiation poses a risk of cancer. Or the hazard — or peril — itself. (For instance: Among cancer risks that the people faced were radiation and drinking water tainted with arsenic.)
smoking: A term for the deliberate inhalation of tobacco smoke from burning cigarettes.
THC: Short for tetrahydrocannabinol. It’s the primary active ingredient in marijuana that’s responsible for the mind-altering “high” associated with smoking or eating parts of the Cannabis sativa plant.