Summary
Summary PSYCH1000 Chapter 5 lecture & textbook notes
- Course
- Institution
- Book
Includes integrated information from chapter 5 of the textbook as well as corresponding content from lecture. One-stop-shop for your PSYCH1000 final!
[Show more]
Connected book
Book Title:
Author(s):
- Edition:
- ISBN:
- Edition:
More summaries for
-
Test Bank for Psychology Frontiers And Applications 7th CANADIAN Edition Passer / All Chapters 1 - 17 / Full Complete 2023 - 2024
-
Complete Test Bank Psychology Frontiers And Applications 7th CANADIAN Edition Passer Questions & Answers with rationales (Chapter 1-17)
-
TEST BANK FOR PSYCHOLOGY: FRONTIERS AND APPLICATIONS 7TH CANADIAN EDITION MICHAEL W. PASSER RONALD E. SMITH MICHAEL ATKINSON JOHN MITCHELL ISBN-10: 1260065782 ISBN-13: 9781260065787
Seller
Follow
dlbrenn
Content preview
PSYCH1000: CHAPTER 5: SENSATION & PERCEPTIONSensory Processes
• Sensation: the ways your sense organs receive/transmit info
• Perception: brain’s processing/interpretation of that info
• Psychophysics: study relation between physical stimuli and psychological responses
• Absolute threshold: lower limit of stimuli detectability (ex. how far away we detect light)
• Difference threshold: amt of change required for JND (just noticeable difference)
• Helps to determine relationship between stimuli + what is perceived
• Weber’s Law
• Size of difference threshold relative to physical intensity of test is constant (∆I/I =C)
• ∆I = difference between initial stimuli intensity and the intensity when JND reported
• I = initial stimuli intensity
• C = Weber’s Constant
• Ex. If stimuli is 50 db & you report JND at 55 db, (5/50 —> Weber’s constant is 1/10)
• ∴ at 100db, we can expect JND at (by back calculating ∆I)
• Smaller C value = more sensitive system
• Fechner’s Law (father of psychophysics)
• Sensation increases w/ the logarithm of intensity (doesn’t agree w/ Weber’s linear theory)
• S = k (logI)
• Steven’s Power Law
• S = k log IN
• This is the best one
• Subliminal stimuli: not consciously perceived
• Subliminal cuts: advertisers adding subliminal messaging to influence consumers
• Doesn’t actually impact consumer behaviour as far as we know
• However: priming does actually tend to influence people (even if it is not perceived)
• Minimum time for a neural response is faster than minimum time for perception
• Adaptation occurs in response to unchanging stimuli
• Senses are classified by energy to which they respond
Commonalities Between Sensory Systems
1. Accessory structures: channel info to more sensitive areas (eg, outer ear)
2. Transduction: receptors turn external info into neural info
3. Coding: (for intensity), eg frequency
4. Interaction: senses bleed into one another (eg. smell in tasting)
Sensory Systems: Vision
• Stimulus: electromagnetic energy / light waves
PARTS OF THE EYE
• Iris: contracts and changes opening of pupil (impacts how much light gets in)
• Cornea : clear protective cover, focuses image
• Lens: fine tunes (focuses either near or far distance)
• Vitreous humour: jelly in eyeball, keeps shape of ball, pressurizes inside of eye
• Retina: turns light into vision, has receptors on it
• Fovea: most sensitive part of retina
• Optic nerve: bundle of axons from cells in retina that exit eye
• Blind spot: where optic nerve leaves eye, no receptors —> no vision perceived
• Ganglion cells: big cells on retina where axons form optic nerve, output
• Bipolar cells: connected to both ganglion and receptors, collect and pass along info
• Receptor cells: light-sensitive, in retina, where transduction occurs
• Rods: brightness receptors
, • Cones: colour receptors
• Photopigments: proteins in receptor cells which convert light to nerve impulses via
chemical reactions
• Dark adaptation: gradual regeneration of depleted photopigments after bright illumination
• Spectral sensitivity: showing which cones are sensitive to which colours (wavelengths)
• Colour vision
• Trichromatic Theory
• Colour vision is based on activity of 3 types of receptors, each w/ a different peak
sensitivity (short, med, long wavelength) —> red, green, blue
• Balance of activity in S/M/L cones determines perception of colour
• Opponent-Process Theory
• Cone photoreceptors are linked to form 3 opposing colour pairs (blue/yellow, red/green,
black/white)
• Activity in one member of the pair inhibits activity in the other
• This explains why you can’t describe a colour as “bluish yellow” or “reddish green”
• When one member of the pair is “fatigued” by extended exposure, inhibition of the
other member lessens (can lead to this colour being perceived)
• Colour-deficient vision
• Dichromat: someone who has a deficiency in either red-green or yellow-blue systems
(absence of hue-sensitive photopigment in certain cones)
• Monochromat: someone who is only sensitive to black-white system (total colour
blindness)
• Visual info analyzed by feature detectors in primary visual cortex
• Stimulus elements reconstructed/interpreted in visual association cortex
How Do Rods & Cones Work?
• Horizontal cells between bipolar and receptors (inhibitory)
• Amacrine cells between ganglion and bipolar (inhibitory)
• Many more rods than cones
• Rods: operate at low light intensity (sensitive to brightness)
• Fovea does not contain any rods (if you’re looking right at something, less sensitive to light)
• Monochrome (no colour vision)
• Visual pigment called rhodopsin
• Cones: operates at higher intensity (less sensitive to light)
• Concentrated in fovea
• Full colour
• One of 3 photopigments: chlorolabe (Green), erythrolabe (Red), cyanolabe (Blue)
• Responsive to different wavelengths (colour)
• Duplex theory : 2 kinds of visual receptors
• Visual pigments react to light (break down in the presence of light and split into chemicals
which cause action potentials)
• Single cell recording: isolate a single retinal ganglion cell and attach a micro electrode and
record output
• find spot in visual field where ganglion cell is firing the most (thats the area thats served by
that ganglion cell) —> helps us plot a receptive field for a particular ganglion cell
• horizontal cells inhibit the ganglion cell (slow firing rate) right before it hits the hot spot
(areas of max/min response circles) & returns to base firing rate once leaves receptive field
• Lateral inhibition: as one receptor gets activated a lot, it activates horizontal inhibitors and
inhibits next door receptor from firing (helps to enhance / clean up image)
• That is how a ganglion cell’s receptive field is built
Sensory Systems: Audition
• Stimulus: sound waves
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller dlbrenn. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $2.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
79373 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now