PSYC 213 Chapter Notes - Chapter 1: Cognitive Ethology, Metacognition, Computer Data Storage
28 May 2018
School
Department
Course
Professor
Chapter 1: Introduction
Cognitive Psych & Information Processing
• Study of human cognition had 3 stages
1. Rapid progression, based on scientific investigations (stimulus-response) and experimental
psychology
o 1950s-60s
2. Computational analysis & start of cognitive science
o 1970s
3. Based on neuropsychology & animal neurophysiology (brain imaging)
o 1980s
• Stimulus: entity of external environment that can be perceived by observer
• Central idea to cognitive psychology is that world contains information that humans can
process
o Not passive receivers, rather actively select information (active selectors)
o NS has limited processing capacity
• Bit: binary digits, quantifies amount of information given by an event, most basic unit of
information
o Every event occurring in situation with two equally likely outcomes provides one bit
o i.e. toss coin --head or tails gives you one bit of info
• Cognition = information processing
Information Theory
• Information reduces uncertainty in mind of receiver
• Amount info given by message is proportional to probability that particular message will occur
o i.e. "how are you?"
o More improbable information (i.e. bad, I have the flu) is more informative
• Information provided by message not only depends on content, but also on whole array of
possible messages
o More possible messages = less likely to occur = more information conveyed = takes
longer to process
• Information theory: information provided by particular message is inversely related to its
probability of occurrence
o The lower the probability of a message, the more info it contains
Limitations on Information Processing
1. Time taken for information flow through NS
o Hick & Hyman showed takes time to translate visual signal into key-pressed/verbal
response
o As response uncertainty increased, reaction time increased linearly
2. Limit of capacity for information processing
o More info conveyed in signal = more time taken to process & respond
• Webster & Thompson (1953): airport tower operators listening to messages from pilots with
aircraft's call signal & 3 unrelated words
o i.e. BA427, Pencil, Beard, Camera
o Many more possibilities for words than aircraft call signal
o Able to identify call signals from 2 planes arriving at same time but not word messages
• Shows that NS processing capacity limited
