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• Conceptual Knowledge


  Knowledge that enables us to recognize objects and events and to make inferences about their properties
• List of key concepts

  • Basic Properties of Concept and Categories
  • Network Models of Categorization
  • How Concept are Represented in the Brain

  
• Concept


  The mental representation of a class or individual
• Category


  All possible examples of a particular concept
• Categorization


  The process by which things are placed in categories
• How Are Objects Placed into Categories?

  1. Why Definitions Don't Work for Categories

  2. The Prototype Approach: Finding the Average Case

  3. Which Approach Works Better: Prototype of Exemplar
• Why Definitions Don't Work for Categories

  • Not all of the members of everyday categories have the same features
  • Family resemblance: the idea that things in a particular category resemble one another in a number of ways
• Prototype


  A "typical" member of the category
• Typicality


  Variations within categories as representing differences
• Exemplar


  Actual members of the category that a person has encountered in the past
• Levels of categories


  • Superordinate Level (Global Level)
  • Basic Level
  • Subordinate Level (Specific Level)
• What's Special About Basic Level Categories?


  • Participants tended to pick a basic level name (fish) rather than global (animal) or specific level (trout)
• The level that is "special"—meaning that people tend to focus on it—is not the same for everyone</b>
• People with more expertise and familiarity with a particular category tend to focus on the more specific information that Rosch associated with the specific level</b>
• In order to fully understand how people categorize objects, we need to consider not only the properties of the objects but also the learning and experience of the people perceiving those objects</b>
• Semantic Networks


  Concepts are arranged in networks, with nodes representing categories/concepts and links representing relationships
• Hierarchical model


  Consists of levels arranged so that more specific concepts are at the bottom and more general concepts are at higher levels
• Cognitive Economy


  The way of storing shared properties just once at a higher-level node
• Spreading activation


  Activity that spreads out along any link that is connected to an activated node
• The Collins and Quillian model couldn't explain the typicality effect and was questioned for the concept of cognitive economy</b>
• Connectionism


  An approach to creating computer models for representing cognitive processes, also called parallel distributed processing (PDP) models
• Input units


  Units activated by stimuli from the environment
• Hidden units


  Units that send signals to output units
• Output units


  Units that produce the final output
• Connection weight


  Determines how signals sent from one unit either increase or decrease the activity of the next unit
• Four Proposals About How Concepts Are Represented in the Brain

  • The Sensory-Functional Hypothesis
  • The Multiple-Factor Approach
  • The Semantic Category Approach
  • The Embodied Approach
• Category-specific memory impairment


  An impairment in which a person has lost the ability to identify one type of object but retained the ability to identify other types of objects
• Distributed representation


  The idea that concepts are represented by activity distributed across a network, rather than by a single feature
• Semantic category approach


  The idea that there are specific neural circuits in the brain for some specific categories

  
• Embodied approach


  The idea that our knowledge of concepts is based on reactivation of sensory and motor processes that occur when we interact with the object
• Semantic somatotopy


  Correspondence between words related to specific parts of the body and the location of brain activity
• Information about concepts is distributed across many structures in the brain, with each approach emphasizing different types of information
• As research on concepts in the brain continues, the final answer will contain elements of each of these approaches
• Autobiographical memory


  Memory for specific experiences from our life, which can include both episodic and semantic components

  
• Autobiographical memory


  • It is multidimensional
  • We remember some events in our lives better than others

  
• Research by Roberto Cabeza et al. (2004) aimed to show differences between autobiographical memory and laboratory memory

  
• Stimuli: two sets of pictures; taken by participants (own-photos) and taken by other people (lab-photos)
• Participants' task


  1. Identify their own photos and lab photos that they have seen before, and lab photos that they saw just now

  2. Their brain activities were measured using an fMRI scanner

  
• Reminiscence bump


  The enhanced memory for adolescence and young adulthood found in people over 40

  
• Hypotheses for the reminiscence bump

  • Self image hypothesis
  • Cognitive hypothesis
  • Cultural life script hypothesis