PS260 Study Guide - Final Guide: Semantic Memory, Episodic Memory, Explicit Memory

42 views11 pages
18 Mar 2013
School
Department
Course
Ian Shaughnessy
Cognitive Psychology
Feb 7th 2013
Chapter 5
Object Recognition the process whereby we match an incoming stimulus with stored
representations for the purpose of identification. (identifying and classifying what it is we have
latched on to)
Rosh (1976)
Levels of Categorization also known as gradations of specificity that can be used in describing
everyday categories. 3 levels (ie animal, bird, black-winged chickadee)
i) Super ordinate level of categorization animal is the most general
ii) The midpoint (Basic level of categorization) bird
iii) The subordinate level black-winged chickadee. Is the most specific
-Rosh says that the middle level dominates our cognitive processing
Entry point for recognition the default level of categorization that we use for familiar objects
We use both bottom-up and top-down processing for recognizing objects
-When an object is obstructed, we rely on our knowledge, expectations, and surrounding contexts
to supplement the data (ie top-down)
-Bottom-up is how we identify objects from past data and experiences
Study by Palmer, Rosch, and Chase (1981) on the perspective effects of cognition
-Participants were given a number of pictures of objects
-One group had to rate how well each picture represented the object
-The other group had to indentify the objects as fast as possible
-Recognition turned out to be fasted for pictures rated higher by the first group
Study by Biederman and Gerhardstein (1993)
-Suggested that orientation might not matter at all that much in object recognition
-Used a technique called priming: a gained benefit from an earlier exposure to a stimulus
-Presented an image of a flashlight to participants in Phase 1 and identify it
-Phase 2 had participants identify the same image either the same way or rotated or a similar
image in the same way or rotated
-Phase 1 was very slow but all examples of phase 2 were faster
-This means that seeing the flashlight for phase 1 (or any object) primed identification of all
flashlights. This is called Semantic Priming
-Object rotation did not have a significant enough effect on object recognition
Study of the effects of context in object recognition by Palmer (1975)
-Most studies of objected recognition were in isolation that did not have meaningful context
Unlock document

This preview shows pages 1-3 of the document.
Unlock all 11 pages and 3 million more documents.

Already have an account? Log in
-Sketches of everyday scenes were presented and then sketches of single objects were presented
for identification
-The relationships varied between the scene and the objects
-Some scenes were consistent with the object being presented (kitchen followed by loaf of bread)
-Some scenes were inconsistent with the object (kitchen followed by a drum)
-Some scenes were inconsistent and misleading (mailbox that has features similar to bread loaf)
-Identification of objects were best when the scene was consistent with the object
Study of the effects of context in object recognition by Davenport and Potter (2004)
-Had participants look at a scene followed by a pattern made to erase the just-observed stimuli
called a mask.
-Participants were able to identify what was in the foreground better than the background
-Participants were also able to identify even better if the foreground image was consistent with
the background. (ie football player was identified better if he was in a field rather than a church)
Theories of Visual Object Recognition
1. Parts-Based Approaches
- Incoming patterns are parsed into component parts (ie bunny: little sphere, big sphere, long thin
triangles)
-We then compare these components to information in our memory and recognize that this basic
set of components in this particular combination equals a rabbit
2. Image-Based Approaches
-More holistic process
-We take the whole image and compare it to corresponding representations in the memory until
we find a match.
Parts-Based Approach in More Detail
-The orientation of the features of the object do not matter: Viewpoint-Invariant
Recognition by Components (RBC)
-A parts-based theory proposed by Biederman (1993)
-The features which we identify from objects are three dimensional shapes called geons
-There are 36 geons which serve as visual primitives- simple shapes that form into more complex
shapes
-The geons can be viewed the same way regardless of orientation
-Stages of RBC object orientation
1. Edge extraction looking for differences in features (colour, texture, luminance)
2. Search for non-accidental features features that don’t appear to be an accident
3. Parsing the object in the simplest way possible
4. Geons determined; match with memory representations
5. Object identified
Tarr and Pinker Study (1989) Arguing that sometimes perspective affects recognition
- Presented participants with 3 abstract shapes
- Presented in same orientation until memorized
- Results showed that if rotated, participates had a harder time identifying objects
Unlock document

This preview shows pages 1-3 of the document.
Unlock all 11 pages and 3 million more documents.

Already have an account? Log in
- “Viewpoint dependence”
Image-Based Approach (IB)
- Objects are recognized by comparing the input with a stored replica
-View-point dependent
Template Matching
-Exact match must be found
-Fails to account for the flexibility of object recognition
Chapter 6
Types of Long Term Memory
Declarative Memory
-Is a long term memory system responsible for retention of factual information about the world,
as well as personally experienced episodes.
-Tulving (1972, 1983) believes that declarative memory is divided into two kinds of memory
1. Episodic Memory
referring to one’s memory for personally experienced events that include contextual elements
like the time and place of the event’s occurrence.
-Example would be remembering when you won a baseball game
2. Semantic Memory
-refers to knowledge or information about our world that does not include contextual elements
like the time and place or place the information was learned.
-Example would be when the declaration of independence was signed in 1776
Characteristic
Episodic
Semantic
Likelihood of forgetting
High
Low
Usefulness
Low
High
Recollective Experience
Present
Not Present
Sensory Component
Present
Not Present
Presence of emotion
Present
Not Present
Procedural Memory
-Declarative Memory is “knowing that” and Procedural Memory is “knowing how”
-Examples of procedural memory include skills (tying one’s shoe, swinging a golf club) and the
formation of simple associations (like a classically conditioned taste aversion)
Unlock document

This preview shows pages 1-3 of the document.
Unlock all 11 pages and 3 million more documents.

Already have an account? Log in

Get OneClass Grade+

Unlimited access to all notes and study guides.

Grade+All Inclusive
$10 USD/m
You will be charged $120 USD upfront and auto renewed at the end of each cycle. You may cancel anytime under Payment Settings. For more information, see our Terms and Privacy.
Payments are encrypted using 256-bit SSL. Powered by Stripe.