Cog Psych Unit 3 Lecture 3

where the hierarchy fails

when there is a stronger association between categories due to familiarity

example of hierarchy failing

pig-animal association is faster than pig-mammal association because of familiarity

robin-bird association is faster than turkey-bird because of typicality effect

spreading activation

activation travels through a network

activation decays with distance

example of spreading activation

activation of bread can travel to butter, toast, etc.

stronger links are associated with

more close relations, faster activation

predict semantic priming

Neural signature

EEG reading shows ERP at N400

N400

the cost of semantic integration

lower than the semantic info fits the context of has been primed

higher when the semantic info is unexpected

Connectional model

the mind “learns” concepts through experience

knowledge lives in distributed networks

the brain stores concepts as

patterns of activity produced by connections

initial concepts are set @ a random weight. repeated exposure causes weights of connections to change

brain as hub and spokes model

the anterior temporal “hub” integrates features

category specific deficits result from vs. semantic dementia

lesions outside hub

semantic dementia from damage to anterior temp lobe, causes broad concept loss