Neurons, Hormones, and the Brain

Neural impulses conform to the all-or-none law, which means that a neuron generates an action potential only if a threshold level of stimulation is reached. If the threshold is not reached, the neuron doesn’t fire.

Neural impulses are transmitted from one neuron to another via neurotransmitters. When an action potential reaches the terminal buttons of a neuron, neurotransmitter-filled synaptic vesicles fuse with the cell membrane, releasing neurotransmitter molecules into the synaptic cleft. These molecules link up with receptors on neighboring neurons and generate a voltage change or postsynaptic potential at the receptor site.

There are five noninvasive ways of studying the brain: (1) studying people with brain injuries or diseases, (2) electroencephalograms, (3) computerized tomography, (4) positron emission tomography, and (5) magnetic resonance imaging.

Yes, she could name what she sees. Information about the baseball goes to the left hemisphere, which controls language function.

The pituitary gland is sometimes called the master gland because it releases hormones that control other glands.