The CNS and neurotransmitters

• Made up of the brain and spinal cord • Responsible for processing and transmitting information throughout the body

The CNS controls sensory information, motor commands, and higher functions such as thinking, memory, and decision-making.

• Carries messages between body and brain • Receives sensory info from skin, joints, muscles • Carries motor instructions controlling movement.

• receives info from the senses • processes the info • controls thoughts, memory, emotions and planning. • send instructions back to the body.

Specialised nerve cell that; - Receives - Processes - and transmits info through electrical and chemical signals.

• Cell body: Contains the nucleus and processes information. • Dendrites: Receive electrical signals from other neurons, triggering an action potential within the cell. • Axon: Transmits electrical signals away from the cell body to other neurons or muscles (so to other axon terminals). • Axon terminals: Pass nerve impulses from cell body to the parts of the body they can’t control/activate. terminal boutons at end, bulb-shaped structures - vesticles - store nts for synaptic transmission.

• is a fatty insulating layer around the axon, • speeds up transmission of electrical impulses.

• Neurons transmit electrical impulses throughout the body, allowing communication between the brain, spinal cord, and muscles/organs.

• Motor - transmits messages from CNS to muscles • Inter (relay) - connect neurons to other neurons • Sensory - carry info from senses to CNS

the process by which neurotransmitters are released from the axon terminal of one neuron and cross the synapse to bind to receptors on the dendrites of another neuron, transmitting a signal.

• An action potential travels down the axon to the axon terminal. • Neurotransmitters are released into the synapse. • These neurotransmitters bind to receptors on the next neuron’s dendrites. • The signal is either excited or inhibited, depending on the neurotransmitter and receptor type.

Dopamine is a neurotransmitter involved in regulating mood, motivation, and reward. It plays a key role in pleasure and reward systems and is involved in conditions like Parkinson’s disease and schizophrenia.

Serotonin is a neurotransmitter that regulates mood, appetite, sleep, and memory. It is linked to feelings of well-being and is often associated with depression and anxiety when levels are low. SSRIs increase serotonin levels.

Glutamate is the brain’s main: - excitatory neurotransmitter. It increases neural activity and is important for: - learning, - memory.

Excitatory neurotransmitters: increase likelihood of neuron firing. Inhibitory neurotransmitters: decrease likelihood of neuron firing. Example: glutamate = excitatory GABA = inhibitory

• The method the nerve impulse passes down the axon. • Tiny electrical impulse that’s triggered by change in the electrical ‘potential’ of the neuron. • ‘the electrical impulse travelling down the axon.’

At rest, a neuron has a charge of: -70mV This means the inside is more negative than the outside

Depolarisation occurs when: - positively charged sodium ions enter the neuron, - making the inside more positive. If the neuron reaches: -55mV an action potential is triggered.

Reuptake is when unused neurotransmitters are: - reabsorbed into the presynaptic neuron. This helps “turn off” the signal.