Textbook Notes (368,122)
Canada (161,660)
Psychology (3,337)
PSYC 1000 (740)
Dan Meegan (212)
Chapter

Module 4.docx

7 Pages
85 Views
Unlock Document

Department
Psychology
Course
PSYC 1000
Professor
Dan Meegan
Semester
Winter

Description
Module 4: Neural and Hormonal Systems Biology, Behaviour and Mind - Everything is a biological happening o Ideas, moods urges - Plato o Placed the mind in the head  Aristotle  Placed it in the heart - Gall o Phrenology, study bumps on the head  Reveal persons mental abilities and character traits  Would give skull readings o Failed but focused attention on localization of function  Various brain regions have particular functions - Biological perspective o Concerned with the links between biology and behaviour o Biology of the mind has lead to  The body is composed of cells  Among them nerve cells conduct electricity and “talk” to one another by sending chemical messages across tiny gap separating them  Specific brain systems serve specific function (different from Galls)  And they have subsystems  We integrate information processed in these different brain systems to construct our experiences of sights and sounds, meanings and memories, pain and passion  Our adaptive brain is wired by our experience o Cells organize to form body organs, which form larger bodily systems o Thus biopsychosocial systems Neural Communication - Brain samples of humans and monkeys are same - Able to study neural systems of squids and slugs o All operate similarly Neurons - A nerve cell, a basic building block of the nervous system o Each consists of cell body and branching fibers  Dendrite fibers are bushy branching extensions receiving messages and conduct impulses toward the cell body o Dendrites listen, axons speak o Axons very long several feet  Encased in myelin sheath  Fatty tissue, insulates and speeds impulses  Myelin laid up to age 25, neural efficiency, judgment and self control grow - Transmit messages when stimulated by signals from senses or by chemical signals from neighbouring neurons o Response is firing an impulse  Action potential, brief electrical charge travels down axon  Travels 2-180 miles an hour  3 mil times slower than actual electricity  Brain is more complex than a computer but much slower at simple responses  Slower the bigger the animal - Neurons generate electricity from chemical events (chemistry-to-electricity process) o Ions (electrically charged atoms) are exchanged  Axon outside membrane fluid is positive  Axons interior is negative  This is known as resting potential - Surface picky about what comes through, selectively permeable o Security changes when a neuron fires  First section on axon opens, positive sodium ions come in  Depolarizes axon section causing next to open and so on.. - During resting period (refractory period) o Positive ions are pumped back outside o After this can fire again - In myelin neurons speeds up because hopes from one end to the next - Types of signals o Excitatory  Pushes a neurons accelerator o Inhibitory  Pushes the brake o Is excitatory minus inhibitory exceed threshold  Level of stimulation required to trigger a neural impulse  Combined signal trigger action potential - Then travels down axon, and branches into junctions - Increasing level of stimulation does not increase neural impulse’s intensity o All or nothing response o Strong stimulus trigger more neurons to fire  Doesn’t affect potential strength or speed How Neuron’s Communicate - Once thought neurons were fused to each other - Sherrington o Neural impulses take longer than they should  Brief interruption in transmission o Synapse  Meeting point between neurons  Less than millionth of an inch wide - Cajal o Protoplasmic kisses - When action potential reaches axon end releases chemical messengers o Neurotransmitter molecules cross synaptic gap, bind to receptor sites on receiving neuron, electric charged ions flow in - Reuptake o Neurotransmitters reabsorption by the sending neuron How Neurotransmitters Influence Us - Neurotransmitters interact, effects vary with receptors they stimulate - Acetylcholine o Learning and memory o Messenger between every junction of:  Motor neurons  Carry info from spinal cord to tissue  And skeletal muscles o When Ach released muscle cell receptors, muscle contracts  When blocked we cannot move (under anesthesia) - Pert+Solomon o Attached radioactive tracer to morphine  Showed where it was taken in the brain  Bound to receptors linked with mood and pain - Brain produces own natural opiates o Released on response to pain and exercise, endorphins Nerotransmittters and Their Functions Neurotransmitter Function Examples of Malfunctions Acetylcholine Enables muscle action, learning With alzheimer
More Less

Related notes for PSYC 1000

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit