6. Pain pathways

Reflex arcs, lower motor neurones, upper motor neurones, the cerebellum, basal ganglia, the frontal cortex and even decussations get a mention.

We cover the neuroanatomy, and a little neuroscience, of how pain is perceived by the brain and how analgesics and the brain itself can modify this.

Phil talks about the neuroscience of addiction and withdrawal.

Phil and Sam talk about the anatomy of the autonomic nervous system, the neurotransmitters involved and pharmacological targets.

Phil tries to teach Sam about neurotransmitters and how they work. We work through a list of the main neurotransmitters and give an overview of their functions.

Phil tells Sam why his weight is fairly stable, what happens in his brain when he gets hungry and what changes when he has eaten. We talk about the adipostat, leptin, ghrelin and obesity, why we choose particular foods and how dopamine, opioids and (probably) serotonin are involved.

Phil describes the electrochemical nature of action potentials, the different phases and how a neuron transmits a signal along its length and from neuron to neuron.