Literatuur week 2
3.1 Neurons Are the Basic Units of the Nervous System
Neurons are nerve cells. They receive, integrate, and transmit information in the nervous system.
Complex networks of neurons sending and receiving signals are the functional basis of all psychological
activity. Each neuron communicates with tens of thousand of other neurons. They communicate
selectively with other neurons to form circuits (neural networks).
The somatic nervous system is involved in voluntary behavior. The autonomic nervous system is
responsible for the less voluntary behavior.
Functions of neurons
Nerve cells are powered by electrical impulses and communicate with other nerve cells through
chemical signals. During the reception phase neurons take in the chemical signals from neighboring
neurons.
Integration: incoming signals are assessed.
Transmission: neurons pass their own signals to yet other receiving neurons.
Sensory neurons: Detect information from the physical world and pass that information along to the
brain, usually through the spinal cord.
Somatosensory nerves: The sensory nerves that provide information from the skin and muscles.
Motor neurons: Neurons which direct muscles to contract or relax, thereby produce movement.
Reflex: Automatic motor responses.
, Neuron structure
A typical neuron has four structural regions that participate in communication functions:
- Dendrites
o Branchlike extensions of the neuron that detect information from other neurons.
- Cell body/Soma
o Site in the neuron where information from thousands of other neurons is collected and
integrated.
- Axon
o Long, narrow outgrowth of a neuron by which information is conducted from the cell
body to the terminal buttons.
- Terminal buttons
Nerve in reference to a ‘pinched nerve’: In this context, a nerve is a bundle of axons that carry
information between the brain and other specific locations in the body.
Synapse is the site where chemical communication occurs between neurons. Neurons do not touch one
another. The synapse is a tiny gap between the terminal buttons of the ‘sending’ neuron and the
dendrite of the ‘receiving’ neurons.
The outer surface of a neuron is a membrane, a fatty barrier that does not dissolve in the watery
environment inside and outside the neuron. The membrane is semi-permeable. In the membrane are ion
channels, these allow ions to pass in and out of the cell when the neuron transmits signals down the
axon. Ions are electrically charged, some negative and some positive. The electrically charged molecules
are the basis of the neuron’s electrical activity and their movement is controlled by the membrane.
3.4 The Ability to Study Brian Function Has Improved Dramatically
Phrenology is the practice that believed that if a person used a particular mental function more than
other mental functions, the part of the brain where the emphasized function was performed would grow.
This growth would produce a bump in the overlying skull, by carefully feeling the skull, one could
describe the personality of the individual (Gall and Spurzheim).
The first strong evidence that brain regions perform specialized functions came from Broca. He found
out that the front left side of the brain was important for speech. This region is now called Broca’s area.
Measurement of bodily systems influenced by mental states is called psychophysiological assessment.
Researchers examine how bodily functions change is association with behaviors of mental states.
3.1 Neurons Are the Basic Units of the Nervous System
Neurons are nerve cells. They receive, integrate, and transmit information in the nervous system.
Complex networks of neurons sending and receiving signals are the functional basis of all psychological
activity. Each neuron communicates with tens of thousand of other neurons. They communicate
selectively with other neurons to form circuits (neural networks).
The somatic nervous system is involved in voluntary behavior. The autonomic nervous system is
responsible for the less voluntary behavior.
Functions of neurons
Nerve cells are powered by electrical impulses and communicate with other nerve cells through
chemical signals. During the reception phase neurons take in the chemical signals from neighboring
neurons.
Integration: incoming signals are assessed.
Transmission: neurons pass their own signals to yet other receiving neurons.
Sensory neurons: Detect information from the physical world and pass that information along to the
brain, usually through the spinal cord.
Somatosensory nerves: The sensory nerves that provide information from the skin and muscles.
Motor neurons: Neurons which direct muscles to contract or relax, thereby produce movement.
Reflex: Automatic motor responses.
, Neuron structure
A typical neuron has four structural regions that participate in communication functions:
- Dendrites
o Branchlike extensions of the neuron that detect information from other neurons.
- Cell body/Soma
o Site in the neuron where information from thousands of other neurons is collected and
integrated.
- Axon
o Long, narrow outgrowth of a neuron by which information is conducted from the cell
body to the terminal buttons.
- Terminal buttons
Nerve in reference to a ‘pinched nerve’: In this context, a nerve is a bundle of axons that carry
information between the brain and other specific locations in the body.
Synapse is the site where chemical communication occurs between neurons. Neurons do not touch one
another. The synapse is a tiny gap between the terminal buttons of the ‘sending’ neuron and the
dendrite of the ‘receiving’ neurons.
The outer surface of a neuron is a membrane, a fatty barrier that does not dissolve in the watery
environment inside and outside the neuron. The membrane is semi-permeable. In the membrane are ion
channels, these allow ions to pass in and out of the cell when the neuron transmits signals down the
axon. Ions are electrically charged, some negative and some positive. The electrically charged molecules
are the basis of the neuron’s electrical activity and their movement is controlled by the membrane.
3.4 The Ability to Study Brian Function Has Improved Dramatically
Phrenology is the practice that believed that if a person used a particular mental function more than
other mental functions, the part of the brain where the emphasized function was performed would grow.
This growth would produce a bump in the overlying skull, by carefully feeling the skull, one could
describe the personality of the individual (Gall and Spurzheim).
The first strong evidence that brain regions perform specialized functions came from Broca. He found
out that the front left side of the brain was important for speech. This region is now called Broca’s area.
Measurement of bodily systems influenced by mental states is called psychophysiological assessment.
Researchers examine how bodily functions change is association with behaviors of mental states.
