Cognitive Enhancers: Cholinesterase Inhibitors and NMDA Receptor Antagonists

'Cognition' encompasses various aspects of mental function, assessed using tests like the Cambridge Neuropsychological Test Automated Battery.

Cognitive enhancers, or nootropic drugs,  boost mental function and are used as performance enhancers.

Acetylcholinesterase inhibitors improve memory and cognition in mild to moderate cases of Alzheimer's disease. However, they can induce unwanted cholinergic effects such as salivation, lacrimation, drowsiness, urinary retention, and bowel disorders.

NMDA antagonists alter synaptic plasticity and the brain's circuit function.

Synaptic plasticity involves long-term potentiation and depression, induced by glutamate receptor activation and modulated by dopamine.

Memantine inhibits NMDA receptor-mediated excitotoxicity. It also limits neuronal Ca²⁺ influx, preventing intracellular toxic levels. It is used in moderate to severe cases of Alzheimer's disease.

Other drugs include modafinil, which increases extracellular dopamine levels and glutamate release while inhibiting the release of GABA. It is used in ADHD treatment.

Piracetam, a positive allosteric AMPA receptor modulator, helps improve memory and cognition.