Biological Psychology Notes

Glial cells: (glial measn glue)- and also plentiful

Astrocyte- communicates closely with neurons, increase the reliability of their transmission, control blood flow in the brain, and play a vital role in the development of the embryo.

- intimately involved in thought, memory and the immune system

-we can find astrocytes in a great supply in the blood-brain barrier, a fatty caoting that wraps around tiny blood vessels

- blood brain barrier is the brains way of protecting itself from infection by bacteria and other intruders

Oligodendrocyte- promotes new connections among nerve cells and release chemicals to aid in healing.

-produces an isulating wrapper around the axons caleed myelin sheath

myelin sheath- contains gaps along the axon called nodes- helps the neuron conduct electircity more efficiently

Neurons respond to neurotransmitters by generating electrical activity. Electrical activity from neurons using electrodes, small devices made from wire or fine glass tubes. These allow them to measure the potential difference in electrical charge inside versus outside the neuron. The basis of all electrical responses in neurons depends on an uneven distribution of charged particles across the membrance surrounding the neuron.

Resting potential- when there are no neurotransmitters acting on the neuron, the membrane is at the resting potential. In this stage, there are more negative particles inside tha outside the neuron.

Threshold- when the electrical charge inside the neuron reaches a high enough level relative -to the outside, an action potential occurs.

Action potential- abrupt waves of electric discharge triggered by a change in charge inside the axon

-originate in the trigger zone near the cell body and continue all the way down the axon to the axon terminal.

- during this stage, positively charged particles flow rapidly into the axon and then just as rapidly flow out, causing a spike in positive charge followed by a sudden decrease in charge, with the inside charge ending up at a slightly more negative level than its original resting value. These sudden shifts in charge produce a release of electricity. When the electrical charge reaches the axon terminal, it triggers the releasee of neurotransmitters- chemical messengers-into the synapse.

Abosolute refractory period- brief interval during which another action potential cant occur.

Chemical events initiated by neurpotransmitters orchestrate communication among neurons.

After neurotransmitter molecules are released into the synapse,