Understanding Drug Addiction and Its Neuroscience

Drug Addiction

Chronic, relapsing brain disease characterized by compulsive drug-seeking behavior despite harmful consequences.

Dopamine System

Drugs increase dopamine release in the brain's reward pathway.

Tolerance

Reduced response to drugs over time, requiring higher doses for the same effect.

Sensitization

Heightened response to repeated drug exposure.

Conditioned Place Preference

Animals prefer environments associated with drug administration.

Locomotor Sensitization

Increased activity in response to repeated drug exposure.

Self-Administration

Animals voluntarily consume drugs, demonstrating reinforcing properties.

Genetics

Small contribution; specific gene variants may increase susceptibility to addiction.

Age of First Use

Early use increases addiction risk.

Habituation

Decrease in responsiveness to a stimulus after repeated exposure.

Sensitization (Learning)

Increase in responsiveness after a single strong or repeated weak stimulus.

Eric Kandel

Nobel Prize (2000) for work on synaptic plasticity.

Aplysia Experiments

Habituation of Gill Reflex: Repeated siphon stimulation leads to reduced gill retraction.

Classical Conditioning

Associating a stimulus with a response.

Operant Conditioning

Learning through rewards or punishments.

Henry Molaison (Patient HM)

Lost ability to form new declarative memories (anterograde amnesia).

Cerebral Cortex

Stores long-term memory (e.g., personal and semantic memory).

Hippocampus

Crucial for short-term memory and its consolidation into long-term memory.

Long-Term Potentiation (LTP)

Key to learning and memory.

Neuroplasticity

Brain's ability to reorganize and form new connections.

Neurogenesis

Formation of new neurons in areas like the hippocampus and olfactory bulb.

Cognitive Super-Agers

Individuals with preserved cognitive abilities into their 70s and 80s.

BrainHQ

Cognitive exercises targeting response speed, memory, and attention.