Class Notes (838,384)
Canada (510,870)
Psychology (3,528)
PSY100H1 (1,637)
Lecture 5

PSY100H1 Lecture 5: The Brain

4 Pages
Unlock Document

Dan Dolderman

Monday 27th September 2016 PSY100 - Lecture 5 - The Brain “The question of how the ebb and flow of a highly developed mind can be catered to by a physical brain, and the related question of how the one impacts the other, are the hardest-ever challenges to human ingenuity and imagination.”
 - Susan Greenfield (from the Private Life of the Brain, 2000) Recap These tools help cover what you may have forgotten during an experiment: Confounds: What are you manipulating? Third variable: Correlations Operationalization: Measuring things Consciousness - A Multi-Level Process 1. Neurochemical/ cellular: Neurotransmitters and neurons
 2. Neuroanatomical: Major brain structures and their organization
 3. Physiological: major contributions of physiological systems e.g. autonomic nervous system, hormones There is also a social level: while it isn't really neurochemistry, it effects a person’s neurochemistry. There is also the physical environment, which effects you. Example: Learning in Convocation Hall vs a room of 20 people leads to different learning experiences, and how much information you absorb. Structure of a Neuron * You must be able to understand the functions of and label the neuron. Read the textbook for the full process. Dendrites Axon Hillock - Receives information from other neurons and transmits it toward the cell body - Lined with protein receptor sites, which acts like a harbour for boats to dock. These “boats” are packages of info meant to reach the axon terminals. - Makes decisions to fire/not fire information depending on signals called neurotransmitters. Monday 27th September 2016 Neurotransmitters - Relays information between neurons in order to pass on information • Excitatory chemicals: • Stimulates the brain and allows information to be passed • Inhibitory chemicals: Calms the brain • The neuron’s cell body is the official decision maker. • There is an electrical decision making process. • The electrical potential that lies across the cell membrane changes as the “mind makes up its mind” • - electrically make decision making process write up process about the electrical functions - Inhibitory signals are taken to the receptor parts of the dendrites and start a chain of processes, the outcome of which increases the polarity across the membrane (increases net negative charge). - - Excitatory signals decrease the net negative charge. The cell has to depolarize (less negative charge) to the threshold point (-40 to -55 millivolts). Once the threshold point is crossed, ion gates open. Axon Hillock: Place where ionic concentration starts to accumulate, which effectively depolarizes the next segment in the axon. More ions flood in and depolarize the next micro segment and so on with the flow of the action potential (refer to diagram). -xon Long fibre that conducts impulses away from the cell body - This happens through successive opening and closing of ion channels - Ions rush in, in an electrically regulated process (since the channels are voltage gated) - Once the ions flood in, in a short amount of time, the next gate leading to the next micro segment opens, and the one “behind” them closes. - The ions have only one direction to go. The professor put up a slide with this paragraph from Wikipedia for clarification. Action potentials are generated by special types of voltage-gated ion channels embedded in a cell's plasma membrane.These channels are shut when the membrane potential is near the resting potential of the cell, but they rapidly begin to open if the membrane potential increases to a precisely defined threshold value. When the channels open (in response to depolarization in transmembrane voltage), they allow an inward flow of sodium ions, which changes the electrochemical gradient, which in turn produces a further rise in the membrane potential
More Less

Related notes for PSY100H1

Log In


Join OneClass

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

Sign up

Join to view


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.