Glossary Addiction Flashcards
ABUSE
Non-medical use of a substance. It can be a pre-phase of addiction, and it generally follows the recreational use of a substance.
ADDICTION
Use/active seeking of a substance characterized by loss of control and use/seek despite its negative
effects/consequences
ALCOHOL:
addictive substance whose receptor profile is multifaceted. It mainly acts on GABAa receptors (acute
effects) disinhibiting DA cells in the brain reward circuitry.
AMPHETAMINE:
psychoactive addictive substance that act directly on DA transmission by blocking DA reuptake
(DAT-dopamine transporter) and enhancing the activity of VMAT. Result is more DA in the brain reward circuitry
AMYGDALA
structure located in the limbic system involved in emotional control and fear responses.
ATTENTION
cognitive function by which we can filter out irrelevant information and focus on relevant stimuli.
BASAL GANGLIA
heterogeneous subcortical nuclei involved in motor response, and motor behavior (e.g.
movement scaling). They also play a role in habitual behavior, reinforcing the seeking behavior after initial
acquisition of a given substance.
BLOOD BRAIN BARRIER
barrier made by tons of capillaries that protect the brain from external insults.
Psychoactive drugs can pass through it exerting their role in the CNS.
BRAIN REWARD CIRCUITRY
part of the limbic system involved in pleasant/aversive experience. It responds to
rewarding/aversive stimuli promoting a release or inhibition of the neurotransmitter dopamine from the ventral
tegmental area to the nucleus accumbens
BENZODIAZEPINES:
Medical prescriptions with addictive potential acting of GABA transmission. They modulate
anxiety.
CLEAR UP
removal of a neurotransmitter from synaptic cleft. Some drugs interfere with it (se. cocaine for DAT).
COCAINE:
highly addictive substance which directly interacts with DA transmission. Acute effect is given by a
profound blockade of DAT. Result is more dopamine in the brain reward circuitry.
CRAVING
spasmodic need of a substance which has created dependence in a given subject.
DBS:
technique by which implanted electrodes stimulate a given brain region involved in a specific behavior. It is
widely used to treat Parkinson and trials have been done also to treat alcoholism.
DECISION MAKING:
cognitive
function by which a specific behavior can be manifested based on expectancies and analysis of the outcomes.
DEPRESSANT:
in addiction science is the effect of a substance that cause sedation in a given subject. Many
sedatives/depressant act indirectly on DA transmission.
DESENSITIZATION:
lack of response to a specific substance because of neurochemical adaptations of the
receptors which normally mediate the effects of that substance.
DOPAMINE:
neurotransmitter involved in pleasure/aversion. It is the maestro of the limbic/reward system. All
the substances that create dependence promote an acute release of DA in the nucleus accumbens.
DRUG:
Substance other than food that once administered produces an effect due to a molecule/receptor
interaction. If it passes the BBB is called psychoactive (in many cases). Addictive drugs can be natural (extracted
from plants) or synthetic (chemically synthetized, LSD).
DSM
manual where the criteria for a give mental disorder are stated. There is a section also for addiction.
ECSTASY:
hallucinogen drug with low addictive potential. It causes hallucinations acting on serotonin
transmission (Raphe)
Endocannabinoids
family of lipid molecule, enzymes and receptors which play substantial role on neuronal
protection and plasticity. The most important molecules are anandamide and 2-AG and they are normally
produced on demand in the post synaptic neurons, from where they are released to modulate the presynaptic
release of a given neurotransmitter. They act at the level of CB1 and 2 receptors. The former are also the sites
where THC acts.
GABA:
the major inhibitory neurotransmitter of the CNS. Activity on its receptors inhibits the cell. Many drugs
(e.g. alcohol and opiates) work on GABARs to indirectly increase DA release in the brain reward circuitry.
GAMBLING
(pathological): loss of control derived by spasmodic need of playing with slot machines and so forth.
It activates the same circuitries as drugs.
GATEWAY HYPOTHESIS
hypothesis according to which the early use of soft drugs (e.g. cannabis) paves the way
to the use of hard drugs (e.g. opiates)
GLUTAMATE
the major excitatory transmitter in the CNS. It normally activation of AMPA and NMDARs. It is
involved in plasticity and important for chronic effects of substance use.
HALLUCINOGENS
drugs able to cause perception of non-existing objects (hallucinations). Acting mostly on
serotonin and poorly on DA they have low addictive profile.
HEROIN/MORPHIN:
highly addictive substances which mainly act on mu opioid receptors. These receptors are
mostly expressed on GABA interneurons in the brain reward circuitry. MuRs are Gi-couples receptors, thus their
activation causes an inhibition of GABA release. The result on DA neurons in increase in their firing activity and
release of DA.
HIPPOCAMPUS
part of the limbic system involved in long-term memory/consolidation. It also relates to drug
memory so it has a role in craving and relapse.
INHBITORY CONTROL:
control of impulses that leads to balanced behavior in front of external stimuli based on
expectancies and outcomes.
KETAMINE
addictive substance that causes sedation and analgesia acting of opioids receptors.
LIMBIC SYSTEM:
See brain reward circuitry which is a part of it. System in the limbus (border between new brain
(6 layer cortex) and allocortex (3-4 layer cortex)). It is involved in memory and emotion.
LOSS OF CONTROL:
reduction of inhibitory control leading to poor judgement in front of a given
external/rewarding stimulus. The basis of drug seeking despite negative consequences.
LSD:
hallucinogen with low addictive property acting on serotonin transmission.
MOTIVATION:
behavior triggered by the expectancy of a given reward, or avoidance of a punishment.
NICOTINE:
Highly addictive substance that acts at the level of nicotinic acetylcholine receptors. These receptors
are widely expressed throughout the whole body (e.g. muscles) and in the brain reward circuitry. It promotes a
both direct and indirect release of DA.
NUCLEUS ACCUMBENS
part of the ventral striatum involved in the primary rewarding responses to addictive
substances.
OPIOD SYSTEM
neuromodulatory system activated by endogenous (among the others) endorphins. Involved in
anesthetic and analgesic functions.
PAPEZ CIRCUITRY
circuitry mainly made by hippocampus, enthorinal and cingulate cortex involved in emotional
control and expression
PREFRONTAL CORTEX
the executive cortex, by which we execute tasks based on expectancies and analysis of
outcomes. Involved in high evolved functions (judgment and so forth).
RELAPSE
einstatement of an addictive behavior.
REUPTAKE:
pick up of neurotransmitter (mainly) into the presynaptic neurons after clear up.
REWARD
positive reinforcement as result of a given behavior. Opposed to punishment.
SEEKING BEHAVIOR
active search of a specific reward.
SEROTONIN
neurotransmitter involved in modulation of mood. At the level of serotoninergic transmission the
hallucinogens work.
STIMULANTS
a drug that induces euphoria and activation.
THALAMUS
a sensorial hub that sends to the cortex filtered sensorial information coming (e.g.) from the PNS
THC:
active principle of cannabis sativa. Acts as partial agonist at the level of the CB1-Rs.
TOLERANCE
reduced response to a given substance.
VMAT:
transporter involved in the packaging of monoamines (e.g. DA) in the vesicles for release.
WITHDRAWAL
negative symptoms derived by the absence of given substance in the brain/body.
