The Brain, Nervous System and Behavior
Neuron: The basic unit of the nervous system, the “nerve cell” is a long thin call which receives, processes, and generates “messages” (neurological impulses) to and from the brain, as well as within the brain itself.
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The neuron is made up of various structures |
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Dendrites – the receptors of the neuron which receive stimulation. |
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Cell body - the part of the neuron which perfume metabolic activity, generates nervous impulses, and transmits outgoing impulses; |
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Cell nucleus – the “core” of the neuron which contains the genetic material; |
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Axon – the fiber shaped part of the neuron which transmits impulses to other neurons or receptors by forwarding them to the end of the branches (axon terminals) where they are released to other neurons, muscles or glands of the body; |
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Myelin sheath – the fatty protective tissue that covers, insulates and protects neurons, as well as speeding up the process of neural transmissions; |
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The nodes (nodes of Ranvier) – the constriction along the axon which serves to speed up the transmission of neurological transmissions; |
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Terminal branches – The parts of a neuron that send messages to other neurons or to muscles or glands. |
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Synaptic knobs (“bouton”) – enlarges tips at the end of the axon terminals (end branches) where the synaptic vesicles are located. |
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Synaptic vesicles – the very tiny “sacks” which contain neurotransmitters; |
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Synapse – the space between the axon of one neuron and the dendrites of another |
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Types of neurons |
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Afferent Neurons |
Neurons which transmit impulses from the various sensory organs to the central nervous system (also known as sensory neurons). |
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Association Neurons |
Neurons which transmit impulses between neurons within the nervous system (also known as connecting neurons). |
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Efferent neurons |
Neurons which transmit impulses from the central nervous system to various glands, muscles, and organs systems of the body. |
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Branches of the Nervous System |
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Central Nervous System (CNS) |
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Peripheral Nervous System (PNS) The part of the nervous system that is made up of nerves (bundles of neurons “ganglia” ) which exist outside the brain and spinal cord, that extend throughout the body. |
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Autonomic Nervous System (ANS)
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The human brain and Central Nervous System (CNS) have been described as the most complex living structure in the known universe. Although rather unimpressive in its appearance, (about the size and shape of a cantaloupe weighing about three and one half pounds) the brain contains billions of neurons and trillion of synaptic connections among them. The brain regulates and controls all of the physical and psychological functions of the human being
Subcortical structures of the brain
Subcortical refers to all the parts of the brain that lie under the cerebral cortex
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Subcortical Structures of the brain |
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Brainstem |
As the spinal cord enters the head, it enlarges and becomes the brainstem (the “hindbrain” or “old brain”), the oldest part of the brain where neurological messages are received; the entry of the twelve cranial nerves that control all vital functions and coordinate reflexes. |
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Medulla |
Responsible for circulation, respiration, digestion, and coordinating autonomic nervous system function; relay station. |
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Pons |
Connects the two hemispheres of the cerebellum, organize reflexes associated with posture, helps maintain balance and equilibrium; helps organize basic movement patters working in coordination with the medulla. |
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Cerebellum |
(Term means “little brain”) coordinates muscular activity and most important function is to initiate and control rapid movement of the limbs (i.e. run, jump a hurdle, kick a ball, throw a ball, etc.); receive and integrate information from various senses and determines which muscle groups to activate. |
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Subcortical Structures of the brain: Midbrain |
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Midbrain |
The region between the “old brain” and the evolutionary “new brain” or cerebrum (Latin word for brain); it is the second anatomical structure to have evolved and is made up of several structures whose functions are interrelated. |
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Reticular Activation System (RAS) |
A network of nerves that controls attention, wakefulness, alertness and states or arousal; serves as a relay station for messages from sensory organs. |
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Thalamus |
A major relay station for information from the body to the cerebral cortex. |
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Hypothalamus |
A small but extraordinary important structure connected to the structures of the limbic system, and directly involved in regulating the internal environment of the body by influencing the autonomic nervous system, controlling the release of hormones, controlling certain drives such as hunger, thirst, sexual arousal, regulating body temperature and helps regulate emotional states such as lust, fear, and rage. |
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Limbic System |
(from the Latin word limbus meaning border or edge) this structure is the border between the older evolutionary parts of the brain (below) and the newest part of the brain (above) and is made up of the Amygdala (connected with the olfactory sense [smell] and its relation to certain drives and emotions), and the Hippocampus (critical to the formation of memories). |
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Anatomically the uppermost part of the brain and the “newest” part in the evolutionary sense, and the mass of tissue which surrounds the suborbital structures, some times referred to as the forebrain, neocortex, or “new brain”.
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cortical Structures of the brain |
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Cerebral Cortex |
The outer part of the brain (cortex from the Latin word for “bark” in anatomical use means outer layer of a structure). It is by far the largest part of the human brain, accounting for about 80 percent of its volume, and its surface area is much greater that it appears because it folds inward in many places. Approximately one third of the surface is visible, and the remaining two thirds is buried within the folds. The cerebral cortex is divided into left and right hemispheres, and each hemisphere is further divided into four lobes that are demarked by rather prominent folds. the lobes are the Frontal, Parietal, Temporal, and the Occipital lobes. |
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Left Hemisphere |
Receives sensory messages from and controls the right side of the body; associated with analytical thought, language and speech, writing, mathematical calculations, step-by-step reasoning, critical thought and other intellectual functions. |
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Right Hemisphere |
Receives sensory messages form and controls the left side of the body; associated with spatial orientation and spatial relationships, pattern recognition, emotionality, music, unstructured thought, intuition and creativity. |
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Corpus collosum |
A thick bundle of interconnecting neurons that connects the two hemispheres and assures constant communication between them. |
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Frontal lobes |
Association cortex associated with planning, problem solving, relating past to present, thinking and a variety of other higher mental processes, including memory. |
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Sensor-i-motor Cortex |
A specialized strip behind the frontal lobes which regulates voluntary movement of the body in response to impulses from other parts of the cortex. |
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Temporal Lobes |
Associated with processing auditory stimuli ad language formation. |
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Parietal Lobes |
Associated with integrating and processing sensory, bodily sensation, touch, texture, etc. |
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Occipital Lobes |
Associated with processing visual stimuli. |
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Important Terms and Concepts |
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Afferent Neurons |
Neurons which transmit impulses from the various sensory organs to the central nervous system (also known as sensory neurons). |
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Association Neurons |
Neurons which transmit impulses between neurons within the nervous system (also known as connecting neurons). |
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Association Cortex |
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Axon |
the fiber shaped part of the neuron which transmits impulses to other neurons or receptors by forwarding them to the end of the branches (axon terminals) where they are released to other neurons, muscles or glands of the body; |
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Brain imaging |
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CAT scan |
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Cell body |
the part of the neuron which perfume metabolic activity, generates nervous impulses, and transmits outgoing impulses; |
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Central Nervous System (CNS) |
The part of the nervous system which consists of the brain and spinal cord. |
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Cerebellum |
(Term means “little brain”) coordinates muscular activity and most important function is to initiate and control rapid movement of the limbs (i.e. run, jump a hurdle, kick a ball, throw a ball, etc.); receive and integrate information from various senses and determines which muscle groups to activate. |
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Cerebral Cortex |
The outer part of the brain (cortex from the Latin word for “bark” in anatomical use means outer layer of a structure). It is by far the largest part of the human brain, accounting for about 80 percent of its volume, and its surface area is much greater that it appears because it folds inward in many places. Approximately one third of the surface is visible, and the remaining two thirds is buried within the folds. The cerebral cortex is divided into left and right hemispheres, and each hemisphere is further divided into four lobes that are demarked by rather prominent folds. the lobes are the Frontal, Parietal, Temporal, and the Occipital lobes |
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Connecting neuron |
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Corpus collosum |
A thick bundle of interconnecting neurons that connects the two hemispheres and assures constant communication between them |
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Electroencephalogram (EEG) |
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Dendrite |
the receptors of the neuron which receive stimulation. |
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Efferent neurons |
Neurons which transmit impulses from the central nervous system to various glands, muscles, and organs systems of the body. |
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Endocrine glands |
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Endorphins |
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Frontal lobes |
Association cortex associated with planning, problem solving, relating past to present, thinking and a variety of other higher mental processes, including memory |
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Ganglia |
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Glia cells |
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Hippocampus |
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Hypothalamus |
A small but extraordinary important structure connected to the structures of the limbic system, and directly involved in regulating the internal environment of the body by influencing the autonomic nervous system, controlling the release of hormones, controlling certain drives such as hunger, thirst, sexual arousal, regulating body temperature and helps regulate emotional states such as lust, fear, and rage. |
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Left hemisphere |
Receives sensory messages from and controls the right side of the body; associated with analytical thought, language and speech, writing, mathematical calculations, step-by-step reasoning, critical thought and other intellectual functions. |
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Limbic system |
(from the Latin word limbus meaning border or edge) this structure is the border between the older evolutionary parts of the brain (below) and the newest part of the brain (above) and is made up of the Amygdala (connected with the olfactory sense [smell] and its relation to certain drives and emotions), and the Hippocampus (critical to the formation of memories). |
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Medulla |
Responsible for circulation, respiration, digestion, and coordinating autonomic nervous system function; relay station. |
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Magnetic resonance imaging (MRI) |
A structural brain imaging method that uses the magnetic. |
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Myelin sheath |
the fatty protective tissue that covers, insulates and protects neurons, as well as speeding up the process of neural transmissions; |
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Neurons |
The basic unit of the nervous system, the “nerve cell” is a long thin call which receives, processes, and generates “messages” (neurological impulses) to and from the brain, as well as within the brain itself. |
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Neuroscience |
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Neurotransmitter |
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Nodes |
the constriction along the axon which serves to speed up the transmission of neurological transmissions; |
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Nucleus |
the “core” of the neuron which contains the genetic material; |
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Parasympathetic division |
which slows down the body, promotes relaxation, regulates heart beat and digestion, etc.) |
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Peripheral Nervous System |
The part of the nervous system that is made up of nerves (bundles of neurons “ganglia” ) which exist outside the brain and spinal cord, that extend throughout the body. |
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Positron emission tomography (PET) |
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Pituitary gland |
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Reticular Activation System (RAS) |
A network of nerves that controls attention, wakefulness, alertness and states or arousal; serves as a relay station for messages from sensory organs |
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Right hemisphere |
Receives sensory messages form and controls the left side of the body; associated with spatial orientation and spatial relationships, pattern recognition, emotionality, music, unstructured thought, intuition and creativity. |







Many thanks for this. Really helpful in a blog post I’m doing
Cheers
Si
siconroy
July 8, 2008 at 7:15 pm
[...] College Class Notes give a nice overview on the brain, nervous system and [...]
Why does Relaxation lead to Creativity and Performance? « Just Seven Things
July 25, 2008 at 7:49 pm
Omg!!! Thanks so well organized. Really helping me with my psychology class!!! Many thanks!!! You’re awesome!!
Gabby
January 16, 2012 at 2:05 pm
your welcome
Joseph Eulo
January 16, 2012 at 2:21 pm