Drugs-dependant plasticity 2

This flashcard set covers the mechanisms of drug-induced neural plasticity, the influence of environment on cocaine sensitization, and the role of neuronal ensembles in drug-context associations.

Causation (in Neuroscience)

The demonstration of a cause-and-effect relationship between drug-induced neuronal changes and behavior, achieved by interfering with those specific neuronal changes.

GluR2-containing AMPAR

The most common form of AMPAR in adult neurons that allows the passage of $Na^{+}$ but not $Ca^{2+}$.

GluR2-lacking AMPAR

A rare form of AMPAR in the adult brain (found in juveniles or after long-term cocaine withdrawal) that allows both $Na^{+}$ and $Ca^{2+}$ to pass through.

NASPM

A specific antagonist used to block GluR2-lacking AMPARs to disrupt behavior like cocaine-seeking.

Incubation of Cocaine-seeking

The phenomenon where cocaine-seeking behavior increases after long-term withdrawal (e.g., $45$ days) compared to early withdrawal (e.g., $1$ day).

Set and Setting

The principle that drug effects are not universal but are significantly influenced by the user's internal state and the external environment.

Home Context

A familiar environment where the subject (e.g., a rat) lives, which typically results in less robust drug sensitization.

Novel Context

A non-home environment that engages more arousal, attention, and learning processes, leading to more robust behavioral sensitization.

Locomotor Sensitization

A behavioral index of drug effect measured by an increase in cage crossovers following repeated drug administration.

Nucleus Accumbens (NAc)

A primary brain reward area divided into the core (AcbC) and shell (AcbS) where cocaine-induced neural plasticity occurs.

Dendritic Spine Density

A measure of synaptic connectivity; specifically, repeated cocaine in a novel context increases this in the AcbC, whereas cocaine at home does not.

Microdialysis

A technique used to measure the release of neurotransmitters, such as glutamate, in specific brain regions like the accumbens.

Cocaine-Context Association

A learned relationship where the behavioral and neuronal effects of a drug are enhanced when the drug is administered in an environment previously paired with its use.

Neuronal Ensembles

Specialized, sparse groups of neurons (often only 2-3 ext{%} of the total) that respond to specific stimuli or encode specific memories.

Hubel and Wiesel Experiments

Foundational studies in the $1950 ext{s}-60 ext{s}$ identifying that specific subsets of neurons in the visual cortex respond only to bars of light in certain orientations.

Fos

A protein marker used to identify behaviorally activated neurons in the brain.

Electrolytic Lesion

A non-selective method of silencing neurons that lacks the specificity required to target only behaviorally activated cells.

c-fos-lacZ Rat

A transgenic rat used in studies to allow for the selective inactivation of behaviorally activated neurons through the expression of $\beta ext{-gal}$.

Daun02

A prodrug that is converted into the neurotoxin Daunorubicin by the enzyme $\beta ext{-gal}$ to selectively kill only activated neurons.

Daunorubicin

The active toxin resulting from the metabolism of Daun02 that causes neuronal death in specific activated ensembles.