PDP Approach
definition
the idea that cognitive processes can be represented by a model in which activation flows through networks that link together a large number of simple, neuron-like units
parallel operations (definition)
multiple, simultaneous activations (other approaches activations are serial = happening at different times)
The connections between neuron-like units are weighted
connection weights = what determine how much activation one unit can pass on to another unit
spontaneous generalizations
Using individual cases to draw inferences about general information
ex. Stereotypes (we look at one person and judge the others to be the same way)
What are 2 other names for the PDP approach?
"Connectionism" and "Neural Networks"
mnemonic to remember
Parallel = simultaneous activations
Distributed = several different locations
by knowing the definitions, you can see the approach refers to multiple activations throughout the brain at the same time
basic unit of a network
Node (neuron-like unit)
* specific nodes link to other nodes to form networks *
When a unit reaches a critical level of activation, it may affect another unit
If the connection weight is positive, it excites the other unit
If the connection weight is negative, it inhibits the other unit
default assignments
Using general information to fill in missing information about an individual
It is the opposite of spontaneous generalization
The PDP approach helps us process highly structured information which includes:
a. pattern recognition
b. language
c. facial recognition
d. all of the above
D. All of the above
T/F: The PDP approach states that special activations happen in only one area of the brain at a time.
False
Activations occur simultaneously, in different areas of the brain
spreading activation (definition)
the process of spreading information from one node to other nodes
The activity is distributed throughout a set of nodes and then activates other, related sets of nodes
Each new experience with a particular item will change the strength of the connection among relevant units by adjusting the connection weights
ex. If you go to Miami and go to the beach, you are strengthening the connection between Miami and the beach. So later on if you hear or think of the word Miami, you will think of the beach.
graceful degradation
the ability to partially recall memory.
ex. Tip-of-the-tongue phenomenon - when this happens, we know what we are trying to think of, but we can only recall partial information, not enough to fully recall it to memory
What are nodes?
a. they are the same thing as neurons
b. they are a complex neuron-like unit
c. they are stored information
d. they are the basic unit of a network
D. They are the basic unit of a network
Current Status
Works better for:
tasks in which several processes operate simultaneously, and
when networks must learn about patterned input from the environment that is highly structured
types of nodes activated
context influences which nodes are activated
This is consistent with situated cognition
Sometimes we only have partial memory for some information. It is not always complete, perfect memory
This is called graceful degradation = the brain's ability to provide partial memory
T/F: Connection weights is the ability to provide partial memory
False
Connection weights are the strength of connection between related nodes/networks
T/F: The PDP approach is consistent with the neurological design of neurons in the brain and thus may provide important links between psychology and neuroscience
True