FACTORS THAT AFFECT NEURAL
Other factors that affect neuronal functioning are the changes in
the extracellular environment and the metabolic demands of the neuron. Neurons
are very sensitive to pH. If the pH becomes too high (more al-kaline), they
start discharging action potentials spon-taneously. If the pH becomes too low,
the opposite happens and the nervous system shuts down.
As can be expected, fluctuating levels of ions, espe-cially sodium,
potassium, and calcium, have a marked effect on impulse production. Similarly,
an increase in body temperature makes neurons more excitable.
Neurons require energy for manufacturing neuro-transmitters and for
maintaining ionic composition. They can be easily injured if metabolic demands
are not met.