psychology homework need ASAP
awilcox10
chapter_2.pptxCourtesy Dr. Julie Gralow
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LO 1 Define neuroscience and explain its contributions to our understanding of behavior.
LO 2 Label the parts of a neuron and describe an action potential.
LO 3 Illustrate how neurons communicate with each other.
LO 4 Summarize various neurotransmitters and the roles they play in human behavior.
LO 5 Recognize the connections between the central and peripheral nervous systems.
Courtesy Dr. Julie Gralow
LO 6 Evaluate pseudopsychology and its relationship to critical thinking.
LO 7 Describe how psychologists use the scientific method.
LO 8 Summarize the importance of a random sample.
LO 9 Recognize the forms of descriptive research.
LO 10 Explain how the experimental method relates to cause and effect.
LO 11 Demonstrate an understanding of research ethics.
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LO 12 Compare and contrast tools scientists use to study the brain.
LO 13 Identify the lobes of the cortex and explain their functions.
LO 14 Recognize the association areas and identify their functions.
LO 15 Distinguish the structures and functions of the limbic system.
LO 16 Distinguish the structures and functions of the brainstem and cerebellum.
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Biology and Behavior: Studying the Last Frontier
Neuroscience
Involves study of the brain and nervous system
Biological psychology
Focuses on how the brain and other biological systems influence human behavior
Contributions
Examination of extent of experience-induced neural plasticity
Courtesy Dr. Julie Gralow
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Biology and Behavior: Studying the Last Frontier
Brandon Burns poses for a photo at the Marine Corps Recruit Depot in Parris Island, South Carolina in the fall of 2003. The following year, he was shot in the head by an enemy sniper in the Battle of Fallujah.
Doctors concluded that some parts of his brain were no longer viable. “They removed part of my skull and dug out the injured part of my brain,” and now, Brandon says, “one third of my brain is gone.”
What were the consequences of his injury?
Brandon Burns in the military
Courtesy Dr. Julie Gralow
Neuroscience
Contributions
Biological psychology
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Courtesy Dr. Julie Gralow
The neuron, the basic building block of the nervous system, has three main components: (1) the cell body, which contains vital cellular structures; (2) bushy dendrites that receive messages from neighboring neurons; and (3) a long, thin axon that sends messages to other neurons through its branchlike terminal buds.
James Cavallini/Photo Researchers, Inc.
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Can you identify the structure of a typical neuron?
Courtesy Dr. Julie Gralow
Cell body: Region of the neuron that a nucleus containing DNA, protein-producing mechanisms, and other structures that nourish the celi
Dendrites: Tiny, branchlike fibers extending from the cell body that receive messages from other neurons and send information in the direction of the cell body
Axon: Skinny tubelike structure of a neuron that extends from the cell body, and which sends messages to other neurons.
Myeline sheath: Fatty substance that insulates the axon and speeds the transmission of neural messages.
Synapse: Tiny gap between a terminal bud of one axon and a neighboring dendrite of the next neuron junction between neurons where communication occurs.
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Cell body
Dendrites
Axon
Terminal buds
Myelin sheath
Synapse
Biology and Behavior
Glia to the Rescue
A scanning electron micrograph shows neurons (green) and glia (orange).
Glial cells serve as the “glue” of the nervous system, providing cohesion and support for the neurons. Thomas Deerinck, NCMIR
Some classes of glial cells
Microglia
Astrocytes
Schwann
Thomas Deerinck, NCMIR / Science Source
Courtesy Dr. Julie Gralow
COMMUNICATION WITHIN NEURONS
THE NEURON AT REST
2. THE ACTION POTENTIAL
3. ACTION POTENTIAL TRAVELS LENGTH OF AXON
Courtesy Dr. Julie Gralow
Communication within neurons
Neural communication involves different processes within and between neurons. In this infographic, we follow the electrical action that conveys messages within the neuron, from one end to the other.
1. THE NEURON AT REST
Before communication begins, the neuron is “at rest.” Closed channels in the cell membrane prevent some positive ions from entering the cell, and the inside of the cell is slightly more negative than the charge outside. At –70 mV, the cell is at its resting potential.
2. THE ACTION POTENTIAL
This graph shows the characteristic electrical trace of the action potential. When the neuron is stimulated, positive ions enter the cell, making the axon less negative (A). When the charge reaches threshold (–55 mV), an action potential is triggered. Positive ions flood the cell, quickly reversing the charge from negative to positive (B). Afterward, the cell is restored to resting potential (C).
ACTION POTENTIAL TRAVELS LENGTH OF AXON
The action potential occurring in one axon segment causes a voltage change in the next, initiating an entirely new action potential there. This sequential action travels along the axon like a wave, carrying the message from axon hillock to terminal buds.
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Biology and Behavior: Studying the Last Frontier
COMMUNICATION WITHIN AND BETWEEN
Resting potential
Electrical potential of cell at rest
Solutions on either side of the membrane wall come into equilibrium; slightly more negative charge inside
Courtesy Dr. Julie Gralow
Biology and Behavior: Studying the Last Frontier
COMMUNICATION WITHIN AND BETWEEN
Action potential
Involves spike in electrical energy that passes through the axon of a neuron, the purpose of which is to convey information
Is all-or-none
Every time a segment of the axon fires
Positive sodium ions flood in from the outside of the cell, while the prior segment returns to its resting potential, all along the length of the axon to its end
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Biology and Behavior: Studying the Last Frontier
COMMUNICATION WITHIN AND BETWEEN
Excitatory signals
Occur when enough combine, sending neurons signal the receiving neuron to pass along message
Inhibitory signals
Inhibit neuron from releasing a signal through the axon
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Biology and Behavior:
COMMUNICATION WITHIN AND BETWEEN
Myelin sheath insulates and protects the tiny spikes in electricity happening inside the axon.
Action potential “skips” over the segments of myelin, hopping from one node to the next, instead of traversing the entire length of the axon.
MYELIN
Protein that envelops and insulates the axon, facilitating faster transmission of the impulse.
Jean-Claude Revy, ISM/Phototake
Courtesy Dr. Julie Gralow
Biology and Behavior: Studying the Last Frontier
COMMUNICATION BETWEEN
Neurotransmitters
Chemical messengers that neurons use to communicate at the synapse
Receptor sites
Location where neurotransmitters attach on the receiving side of the synaptic gap
Reuptake
Process by which neurotransmitters are reabsorbed by the
sending terminal bud
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Biology and Behavior
Axon terminal of a sending neuron interacts with the dendrites of a receiving neuron by releasing chemical messengers (neurotransmitters) into the synapse.
Once the neurotransmitters migrate across the gap and latch onto the dendrite’s receptor sites, the message has been conveyed.
The Synapse
Carol and Mike Werner/Science Source
Courtesy Dr. Julie Gralow
Biology and Behavior: Studying the Last Frontier
COMMUNICATION WITHIN AND BETWEEN
Reuptake
Occurs when neurotransmitters are reabsorbed by the sending bud
Diffusion
Occurs when neurotransmitters are not reabsorbed and drift out of the synaptic gap
Courtesy Dr. Julie Gralow
Courtesy Dr. Julie Gralow
Biology and Behavior: Studying the Last Frontier
NEUOTRANSMITTERS
Acetylcholine
Relays messages from motor neurons to muscles, enabling movement; involved in memory
Too much = spasms; too little = paralysis
Glutamate
Makes neurons fire; central role in memory and learning
Too much = strokes; too little = symptoms of schizophrenia
GABA
Inhibits neurotransmitter firing; contributes to motor control, vision
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Biology and Behavior: Studying the Last Frontier
NEUOTRANSMITTERS
Norepinephrine
Has variety of effects in CNS; helps body prepare for stress
Serotonin
Plays key role in controlling appetite, aggression, and mood; regulates sleep and breathing
Dopamine
Plays role in modulating mood; plays central role in positive reinforcement and dependency
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Biology and Behavior: Studying the Last Frontier
NEUOTRANSMITTERS
Endorphins
Regulates secretion of other neurotransmitter; naturally produced opioids; reduces pain and elevates mood
Agonists
Interfere at level of synapse; increase normal neurotransmitter activity
Antagonists
Interfere at level of synapse; decrease normal neurotransmitter activity
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Biology and Behavior
NEUOTRANSMITTERS
Caffeine
Blocks receptors for adenosine
Increases activity in branch of nervous system serving the body
istockphoto/thinkstock
Courtesy Dr. Julie Gralow
1. Many axons are surrounded by a ______ , which is a fatty substance that insulates the axon.
2. When Brandon was injured, played an important role in his recovery by defending against infection and inflammation of the brain, as well as holding neurons together and maintaining the structure of the nervous system.
a. glial cells
b. dendrites
c. action potentials
d. sodium ions
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3. ________are released into the ________when an action potential reaches the branches of the terminal buds.
Sodium ions; synaptic gap
Neurotransmitters; synaptic gap
Potassium ions; cell membrane
Neurotransmitters; sodium gates
4. Neural communication is very complicated. Draw a diagram depicting the process of neural communication, then explain it to yourself while looking at what you have drawn.
Courtesy Dr. Julie Gralow
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The Supporting Systems
INFRASTRUCTURE
Brain needs supporting infrastructure to carry out directives and relay essential information from outside
Central nervous system (CNS)
Peripheral nervous system (PNS)
Courtesy Dr. Julie Gralow
Central nervous system (CNS): A major component of the human nervous system that includes the brain and spinal cord.
Peripheral nervous system (PNS): The part of the nervous system that connects the central nervous system to the rest of the body.
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THE SUPPORTING SYSTEMS
Overview of the
Nervous System
The nervous system is made up of the central nervous system, which includes the brain and spinal cord, and the peripheral nervous system.
moodboard/Alamy
moodboard / Alamy
Courtesy Dr. Julie Gralow
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The Supporting Systems
Spinal cord
Includes bundle of neurons
Allows communication between the brain and the peripheral nervous system
Connects with the body’s muscles, glands, and organs
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The Supporting Systems
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CONNECTIONS BETWEEN CNS AND PNS
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Sensory neurons
Receive information about the environment from the sensory systems and convey this to the brain for processing
Motor neurons
Carry information from CNS to produce movement; provide mechanism regulated by spinal cord and brain
Interneurons
Resides in brain and spinal cord; act as bridges connecting sensory and motor neurons
Without any input from the brain, the spinal cord neurons are capable of creating some simple reflexive behavior.
While the spinal reflex occurs, sensory neurons also send messages to the brain, letting it know what has happened.
THE SPINAL CORD AND REFLEX ARC
Courtesy Dr. Julie Gralow
Reflex arc: An automatic response to a sensory stimulus, such as the “knee jerk” reaction; a simple pathway of communication from sensory neurons through interneurons in the spinal cord back out through motor neurons.
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Try This
Test your knowledge of the reflex arc using Brandon as an example. As you recall, Brandon’s brain injury led to paralysis on the right side of his body.
What do you think would happen if a doctor tapped on his right knee—would he experience a reflex?
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What Lies Beyond: The Peripheral Nervous System
Peripheral nervous system
Includes all neurons not in CNS
Involves neurons that are bundled together to carry signals throughout body
Nerves
Act as primary communication system for PNS
Supply CNS with information about body’s environment
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What Lies Beyond: The Peripheral Nervous System
SOMATIC NERVOUS SYSTEM
Characteristics
Involves branch of the parasympathetic nervous system
Includes sensory nerves and motor nerves
Gathers information from sensory receptors
Controls the skeletal muscles responsible for voluntary movement
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What Lies Beyond: The Peripheral Nervous System
AUTONOMIC NERVOUS SYSTEM
Characteristics
Regulates involuntary activity
Has two divisions involved in physiological responses to stress or crisis situations
Sympathetic nervous system
Parasympathetic nervous system
Courtesy Dr. Julie Gralow
Sympathetic nervous system: The division of the autonomic nervous system that mobilizes the "fight-or-flight” response to stressful or crisis situations.
Parasympathetic nervous system: The division of the autonomic nervous system that orchestrates the "rest-anddigest”response to bring the body back to a noncrisis mode.
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THE SYMPATHETIC AND PARASYMPATHETIC NERVOUS SYSTEM
PhotoObjects.net/Thinkstock
Courtesy Dr. Julie Gralow
The autonomic nervous system has two divisions, the sympathetic and parasympathetic nervous systems.
In a stressful situation, the sympathetic nervous system initiates the “fight-orflight” response.
The parasympathetic nervous system calms the body when the stressful situation has passed.
PhotoObjects.net/Thinkstock
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What Lies Beyond: The Peripheral Nervous System
TEND AND BEFRIEND
Female response to stress
Many women have inclination to direct energy toward nurturing and forging social bonds as a stress response
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Think Again
MALE BRAIN, FEMALE BRAIN
Studies suggest gender stereotypes can influence performance in math and science.
Research also shows that male and female brains are far more alike than they are different, but...
Certain regions of the limbic cortex and the frontal lobes were larger in women
Areas of the parietal cortex, the amygdala, and hypothalamus were larger in men
So is nature or nurture responsible for gender imbalance in math and the science?
Courtesy Dr. Julie Gralow
Research shows that male and female brains are far more alike than they are different, but some anatomical and functional differences exist.
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The Endocrine System and Its Slowpoke Messengers
ENDOCRINE SYSTEM
Hormones
Pituitary gland
Thyroid gland
Adrenal glands
Can you define each of these?
Courtesy Dr. Julie Gralow
Endocrine system: Communication system that uses glands, rather than neurons to convey messages.
Hormones: Chemical messengers released into the bloodstream that influence mood, cognition, appetite, and many other processes and behaviors.
Pituitary gland: The pea-sized gland located in the center of the brain just under the hypothalamus; secretes hormones that dictate the release of hormones by other glands; known as the master gland.
Thyroid gland: Gland of the endocrine system that regulates the rate of metabolism by secreting thyroxin.
Adrenal glands: Part of the endocrine system involved in responses to stress as well as the regulation of salt balance.
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The Endocrine System
left: (face) Hemera/Thinkstock, (body) Yuri Arcurs; right: Asias elects/Getty Images
Courtesy Dr. Julie Gralow
This system of glands communicates within the body by secreting hormones directly into the bloodstream. left: (face) Hemera/Thinkstock, (body) Yuri Arcurs; right: Asiaselects/Getty Images
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The Endocrine System and Its Slowpoke Messengers
OTHER ENDOCRINE GLANDS AND ORGANS
Pineal gland
Secretes melatonin
Pancreas
Secretes insulin
Ovaries and testes
Secrete sex hormones
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1. ________ carry information from the central nervous system to activate various parts of the body, such as muscles and glands.
a. Interneurons
b. Dendrites
c. Sensory neuron
d. Motor neurons
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2. When a stimulus causes an involuntary response, we refer to it as a reflex arc; the simple communication pathway goes from a sensory neuron through interneurons in the and back out through motor neurons.
a. brain
b. spinal cord
c. axon hillock
d. nodes of Ranvier
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3. The ________ gland, located in the center of the brain, just under the hypothalamus, is in charge of the endocrine system.
4. When confronted with a potentially threatening situation, the sympathetic nervous system sometimes prepares for “fight or flight” and/or “tend and befriend.” How would you explain these two very different responses using the evolutionary perspective?
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The Hemispheres
RIGHT BRAIN, LEFT BRAIN: THE TWO HEMISPHERES
Cerebrum
Includes largest, most highly developed part of brain
Involved in intelligence, personality, thinking, perceiving, planning and organization, language, sensation, motor functions
Divided into right and left hemispheres and covered by corpus callosum
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Two Hemispheres
The cerebrum looks like a walnut with its two wrinkled halves. Regions of the left and right hemispheres specialize in different activities, but the two sides of the brain are constantly communicating and collaborating. Science Source/Photo Researchers, Inc. Colorization by: Eric Cohen
The right hemisphere controls the left side of the body, and the left hemisphere controls the right.
This explains why Brandon, who was shot on the left side of his head, suffered paralysis and loss of sensation on the right half of his body.
Science Source/Photo Researchers, Inc. Colorization by: Eric Cohe
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The Hemispheres
HEMISPHERECTOMY
Christina Santhouse relaxes with her mother at Johns Hopkins, where she had a dramatic brain surgery known as a hemispherectomy.
Prior to the operation, Christina experienced over 100 seizures a day.
William Johnson
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The Hemispheres
SPLIT BRAIN
Hemispherectomies
Exceptionally rare; last resort
Callostomies (Split-brain operations)
Right and left hemisphere disconnected
Both hemispheres
Intact
After
hemispherectomy
MRI SCAN
Medical Body Scans / Science Source
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The Split-Brain Experiment
The image to the right shows a top view of the corpus callosum, the bundle of neurons linking the right and left hemispheres. When the corpus callosum s severed, we can easily see functional differences between the two sides of the brain. Studies of people who have undergone this procedure are is shown here.
Terence H. Williams, Nedzad Gluhbegovic/Wolters Kluwer
1
3
2
Courtesy Dr. Julie Gralow
Information presented to right visual field is processed in left hemisphere where language processing occurs. Subject can speak the answer.
2. Information presented to left visual field is processed in right hemisphere. Subject can’t use language to say what he was shown.
3. The subject can touch the correct object even if he can’t say what has been projected in his left visual field. The subject uses his left hand, which is controlled by the right hemisphere, where the visual information has been processed.
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The Hemispheres
LATERALIZATION
Generalization
Left hemisphere plays a crucial role in language processing and right hemisphere plays a crucial role in managing visual spatial tasks
But
Hemispheres constantly integrate and share information
Courtesy Dr. Julie Gralow
The Hemispheres
LANGUAGE AND THE LEFT
Handedness and dominance
Left hemisphere controls language in most people; do not necessarily correspond to handedness
Language dominance
Broca’s area
Wernicke’s area
Speak Again
Brandon works on his pronunciation in front of a mirror during a speech therapy session at the Memphis VA hospital. You can see the extent of his injury on the left side of his head. Upon awaking from his coma, Brandon could not articulate a single word. Today, he can hold his own in complex conversations.
A.J. Wolfe The Commercial Appeal
Courtesy Dr. Julie Gralow
The Hemispheres
LANGUAGE AREA AND THE BRAIN
Broca’s area
Wernicke’s area
Can you identify the role each structure plays in language production and comprehension?
Wernicke’s area
Broca’s area
Courtesy Dr. Julie Gralow
Broca’s area: An area of the cortex that is critical for speech production.
Wernicke’s area: A region of the cortex that plays a pivotal role in language comprehension.
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The Hemispheres
THE ROLE OF THE RIGHT
Research: Right hemisphere
More proficient in some visual tasks
Critical for understanding abstract and humorous use of language
Better for following conversations that change topics
Important for recognizing faces
Courtesy Dr. Julie Gralow
1. The left hemisphere excels in language and the right hemisphere excels in visual spatial tasks. This specialization of the two hemispheres is known as:
a. split-brain.
b. callosotomy.
c. hemispherectomy.
d. lateralization.
Courtesy Dr. Julie Gralow
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2. A man involved in a car accident suffered severe brain trauma. As he recovered, it became clear he was having difficulty producing speech, even though he could understand what people were saying to him. It is very likely he had suffered damage to the left frontal lobe in a part of the brain referred to as:
a. Wernicke’s area.
b. Broca’s area.
c. the visual field.
d. the corpus callosum.
Courtesy Dr. Julie Gralow
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3. On rare occasions, medication does not work for people with severe seizures. In those cases, doctors might suggest a procedure known as a , which essentially disconnects the right and left hemispheres.
4. The corpus callosum enables information sharing between the two hemispheres. In some cases, surgeons sever the corpus callosum to prevent seizures from spreading between the two hemispheres. How would you explain to a middle school student why this surgical procedure is used and how it is helpful?
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The Amazing Brain
NEUROPLASTICITY
Brain undergoes constant alterations
Physical adaptation and repair—even after hemispherectormy
Growth of new connections and reorganization
Stem cells
Responsible for creating new neurons
HUMAN STEM CELL
Professor Miodrag Stojkovic / Science Source
Courtesy Dr. Julie Gralow
Because stem cells can differentiate into any type of cell in the body, they have great therapeutic potential.
The cells pictured here are derived from a human embryo, but stem cells also reside in various adult tissues such as the brain and bone marrow.
Professor Miodrag Stojkovic/Science Source
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Across the World
THE PLASTIC BRAINS OF OUR CHILDREN
Children and music
Chinese parents believe that piano instruction for their kindergarteners will help school performance.
American parents play classical music to unborn fetuses and how DVDs to their infant and toddler to promote brain development.
Are these parents right in their assumptions?
Courtesy Dr. Julie Gralow
People with musical training generally score higher on language, auditory, and overall IQ tests. (CORRELATIONAL EVIDENCE)
No data demonstrates that listening to music enhances intelligence.
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The Amazing Brain
ALL IN YOUR HEAD
Are you a secretive person? How high is your self-esteem?
The answers to these questions lie on the surface of the skull, or so claimed 19th century phrenologists.
© North Wind Picture Archives / The Image Works
Courtesy Dr. Julie Gralow
The Amazing Brain
TOOLS FOR STUDYING THE BRAIN
Electroencephalogram (EEG)
Computerized Axial Tomography (CAT scan or CT scan)
Positron Emission Tomography (PET)
Magnetic Resonance Imaging (MRI)
Functional Magnetic Resonance Imaging (fMRI)
What are the strengths and limitations of each of these tools?
Courtesy Dr. Julie Gralow
See Table 2.1 and INFORMATICS 2.3 for additional information.
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Social Media and Psychology
FACEBOOK IN THE BRAIN
Facebook friends range from zero to 5000, averaging 245.
A preliminary study suggests friend volume may reflex something about a user’s brain.
There is a correlation between number of Facebook friends and density of gray matter in areas of brain known for social interaction and facial recognition.
So…are your Facebook friends a gray matter?
Courtesy Dr. Julie Gralow
STIMULATING BRAIN CELLS MAY BE TRICKIER THAN
WE THOUGHT
Using a new type of optical imaging, Harvard Medical School researchers observed neurons as they were stimulated by an electrode.
Electrodes caused sparse strings of neurons, rather than a small sphere of surrounding neurons.
Findings suggests a much smaller margin of error during brain surgery and design of neural prosthetics.
Melinda Wenner. Reproduced with permission. Copyright ˝ 2010 Scientific American, a division of NatureAmerica, Inc. All rights reserved.
Electric Surprise
Courtesy Dr. Julie Gralow
1. Scientists hope that in the future they will be able to discover how we can use stem cells to help people like Brandon and Christina. The goal would be for doctors to induce the process of to restore the lost brain tissue.
a. ablation
b. agonists
c. neurogenesis
d. lateralization
Courtesy Dr. Julie Gralow
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2. You have been asked to set up an experiment to determine if playing classical music to infants leads to improved cognitive abilities. What would your independent anddependent variables be? How would your experimental and control groups be treated differently?
3. ________ are responsible for creating new neurons.
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The brain is constantly undergoing alterations in response to experiences and is capable of a certain degree of physical adaptation and repair. This ability is known as:
a. neuroplasticity
b. phrenology
c. ablation
d. lateralization
Courtesy Dr. Julie Gralow
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Courtesy Dr. Julie Gralow
The Cortex: A Peek Beneath the Skull
THE CORTEX
Cerebral cortex
Processes information and surrounds nearly all of the brain structure
Association areas
Involves region of cortex that integrates information from all over the brain.
What does it require to study the brain?
Look at the above illustration for clues.
Courtesy Dr. Julie Gralow
Cerebral cortex: The wrinkled outermost layer of the cerebrum, responsible for higher mental functions, such as decision making, planning, and processing visual information.
Association areas: Regions of the cortex that integrate information from all over the brain, allowing us to learn, think in abstract terms, and carry out other intellectual tasks.
What does it require to study the brain?
In order to study the brain,
we must get to it first. Peel away
the scalp and cut away the bony
skull, and you will find still more
layers of protection. Three thin
membranes—the meninges—
provide a barrier to both
physical injury and infection.
Bypass them, and the outermost
layer of the brain, the cortex,
is revealed.
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THE LOBES: UP CLOSE AND PERSONAL
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The Cortex: A Peek Beneath the Skull
Courtesy Dr. Julie Gralow
THE LOBES: UP CLOSE AND PERSONAL
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Phineas Gage and the frontal lobes
In 1848, Gage was impaled by a 3-foot tamping rod through his cheek, brain, and skull and caused dramatic changes in his personality.
Fritsch and Hitzig and the motor cortex
By applying mild shock to dogs’ cortex, researchers demonstrated that motor cortex region involvement in muscle movement.
Albert Einstein and the parietal lobes
Postmortem comparison of 35 male brain specimens and Einstein’s brain and found the region of Einstein’s parietal lobe responsible for visualspatial cognition and mathematical thinking was 15 percent larger than those of the control group.
The Cortex: A Peek Beneath the Skull
THE LOBES: UP CLOSE AND PERSONAL
Penfield
Used method similar to Fritsch and Hitzig showing which points along the motor cortex and somatosensory cortex corresponded to parts of the body
Developed model that often represented by oversimplified “homunculus”
Courtesy Dr. Julie Gralow
The Motor and
Somatosensory Cortex
PENFIELD’S
MAP
Courtesy Dr. Julie Gralow
This drawing shows how the motor and somatosensory cortex correspond to the various regions of the body.
Parts of the body that are shown larger, such as the face and hands, indicate areas of greater motor control or sensitivity.
The size of each body part reflects the amount of cortex allocated to it.
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The Cortex: A Peek Beneath the Skull
THE LOBES: UP CLOSE AND PERSONAL
Occipital lobes
Is initial processing site for visual information
Primary visual cortex
Connects to optic nerve where visual information is received and interpreted
Courtesy Dr. Julie Gralow
1. The major function of the is to organize information among the other lobes of the brain.
a. parietal lobes
b. frontal lobes
c. corpus callosum
d. temporal lobes
2. The ________ integrate information from all over the brain, allowing us to learn, have abstract thoughts, and carry out complex behaviors.
Courtesy Dr. Julie Gralow
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3. This section introduces the lobes of the cortex and their associated functions. Create a way to remember the lobes and their specific functions using a rhyme or another memorization technique you know.
Courtesy Dr. Julie Gralow
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4. Phineas Gage suffered a horrific accident in the mid-1800s, when an explosion sent a metal rod through his brain and out the top of his skull. Which of the following caused the sudden change in his personality following the accident?
a. damage to his occipital lobes
b. damage to his temporal lobes
c. damage to his frontal lobes
d. damage to his somatosensory cortex
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Digging Below the Cortex
DRAMA CENTRAL: THE LIMBIC SYSTEM
Limbic system fuels basic drives and processes emotions and memories.
Stockbyte/Getty Images
Courtesy Dr. Julie Gralow
Digging Below the Cortex: Identify Functions
Courtesy Dr. Julie Gralow
Hippocampus: A pair of seahorse-shaped structures located in the limbic system; primarily responsible for creating new memories.
Amygdala: A pair of almond shaped structures in the limbic system that processes basic emotions, such as fear and aggression, as well as associated memories.
Thalamus: A structure in the limbic system that processes and relays sensory information to the appropriate areas of the cortex.
Hypothalamus: A small structure located below the thalamus that maintains a constant internal environment within a healthy range; helps regulate sleep-wake cycles, sexual behavior, and appetite.
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Hippocampus
Amygdala
Thalamus
Hypothalamus
Digging Below the Cortex
DEEPER YET: THE BRAINSTEM AND CEREBELLUM
Brainstem
Includes the brain’s core
Extends from spinal cord to forebrain
Forebrain
Involves largest part of brain and includes cerebral cortex and limbic system
Midbrain
Involves brain stem part involved in arousal levels, responsible for generating movement patterns in response to sensory input
Courtesy Dr. Julie Gralow
Digging Below the Cortex
BRAINSTEM AND CEREBELLUM
Reticular formation
Involves network of neurons running through the midbrain
Controls levels of arousal and quickly analyzes sensory information on its way to the cortex
Hindbrain
Pons
Medulla
Cerebellum
Involves muscle coordination and balance
May also affect fine distinctions in cognition
Courtesy Dr. Julie Gralow
Amazing Brains: Amazing People
Three years after his traumatic
brain injury, Brandon celebrated
his marriage to Laura. The couple
recently had their third child, a
daughter named MacCrea Iona.
With her master’s degree in speech–language pathology, Christina now works full time in Pennsylvania’s public school system.
Laura Burns
Courtesy, Bucks County Courier Times
Courtesy Dr. Julie Gralow
1. The represents a group of interconnected structures that process emotions, memories, and basic drives.
a. left hemisphere
b. limbic system
c. corpus callosum
d. superior temporal sulcus
2. The specific part of the brain that processes basic emotions, such as fear and aggression and the memories associated with them, is the ______.
Courtesy Dr. Julie Gralow
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3. How might the specific structures of the limbic system, the brainstem, and the cerebellum come into play if you were out on a first date?
4. The primary role of the thalamus is to:
a. relay sensory information.
b. keep the body’s systems in a steady state.
c. generate movement patterns in response to
sensory input.
d. regulate sleep–wake cycles.
Courtesy Dr. Julie Gralow
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