Textbook Notes (367,933)
Canada (161,513)
Psychology (1,111)
PSYC 221 (51)

PSYC 221 Ch9 Knowledge.pdf

9 Pages
Unlock Document

PSYC 221
Kevin G Munhall

PSYC  221  –  Knowledge     Chapter  9   Knowledge     Concept:  a  mental  representation  used  for  memory,  reasoning,  and  using/understanding   language.     The  best  understood  function  of  a  concept  is  categorization,  in  which  items  are  sorted  into   categories.     Understanding  the  categories  an  object  belongs  to  provides  us  with  much  information  about  it  and   provides  a  quick  way  of  interpreting  the  world.     For  example,  say  you’re  waiting  to  meet  someone  and  they  say  that  they  drive  an  SUV.  With  just   this  information  you  will  be  on  the  lookout  for  a  motorized  vehicle  that  is  medium  in  size  relative   to  other  vehicles.       Definitional  approach  to  categorization:  we  decide  whether  something  belongs  to  a  category  or   not  based  on  whether  it  meets  the  definition  for  that  category.  There  are  many  shortcomings  to   this  approach  since  there  is  huge  variation  in  objects  that  can  clearly  belong  to  the  same  category.       Family  resemblance:  things  in  a  particular  category  resemble  each  other  in  a  number  of  ways  but   do  not  necessarily  need  to  meet  definitional  qualities.  This  approach  was  taken  to  account  for   some  of  the  short-­‐comings  of  the  definitional  approach.     • For  example:  board  games,  card  games,  football  games,  and  Olympic  games  are  all  games,   but  there  is  no  common  definition  that  accounts  for  them  all  to  fit  in  the  same  category.   There  are,  however,  family  resemblances  in  which  they  all  share  a  couple  of  features  that   aren’t  necessarily  definitional  to  a  “game”.       Prototype  approach  to  categorization:  membership  in  a  category  is  based  on  comparing  the   object  to  a  prototype  that  represents  the  category.       Prototype:  a  typical  member  of  the  category.       Prototypicality:  how  closely  a  category  member  resembles  the  prototype  example.       Family  resemblance  can  increase  a  category  member’s  prototypicality.  It  comes  down  to  a  large   overlap  of  common  features.  If  asked  to  write  features  of  chair,  sofa,  mirror,  telephone,  there   would  be  many  common  features  between  chair  and  sofa  but  few  between  the  others.  Even  though   all  four  items  fit  into  the  category  of  “furniture,”  chair  and  sofa  have  higher  prototypicality   because  of  high  family  resemblance.       Sentence  verification  technique:  participant  is  asked  to  answer  “yes”  if  a  sentence  is  correct  and   “no”  if  the  sentence  is  incorrect,  as  quickly  as  possible.       1   PSYC  221  –  Knowledge     Typicality  effect:  people  are  faster  verifying  sentences  that  contain  objects  high  in   prototypicality.  Consider  the  following  sentences.  Reaction  time  would  be  faster  for  the  former:   • An  apple  is  a  fruit.   • A  pomegranate  is  a  fruit.     This  study  looks  at  the  priming  effects  on   prototypicality.  Participants  were  primed   with  the  word  “green”  and  then  shown   two  coloured  circles.  Their  job  was  to   identify,  as  quickly  as  possible,  whether   the  two  circles  were  the  same  colour.   There  were  three  conditions:   • The  circles  were  the  same  colour   and  were  a  good  example  of  the  colour   green.   • The  circles  were  the  same  colour   and  were  a  less  common  example  of  the   colour  green.   • The  circles  were  two  different   colours.     The  diagram  shows  that  reaction  time   was  fastest  for  the  good  example  condition  relative  to  the  poor  example  condition.  This   demonstrates  that  priming  activates  recognition  for  the  prototype  object.     Ways  in  which  prototypicality  affect  behaviour   Effect   Description   Experimental  Result   Family  resemblance   Things  in  a  category  resemble  each   People  rate  highly  prototypical   other  in  a  number  of  ways.   items  as  good  examples  of  the   category.   Typicality   People  react  rapidly  to  objects  that   Faster  reaction  time  in  sentence   are  “typical”  of  the  category.   verification  to  higher   prototypical  object.   Naming   People  are  more  likely  to  list  some   Highly  prototypical  items  are   objects  than  others  when  asked  to   named  first.  Recall  in  class  the   name  objects  in  a  category.   common  top  5  answers.     Priming   Presentation  of  one  stimulus  affects   Faster  same/different  judgments   responses  to  a  stimulus  that  follows.   for  colours  that  are  highly   prototypical.     Exemplar  approach  to  categorization:  members  of  a  category  are  judged  against  exemplars.     Exemplar:  members  of  a  category  that  a  person  has  encountered  in  the  past.  For  example,  if  you   have  seen  sparrows,  blue  jays,  and  robins  in  the  past,  these  are  each  exemplars  of  birds.         2   PSYC  221  –  Knowledge     The  exemplar  approach  has  been  used  to  explain  some  of  the  phenomenon  that  also  support  the   prototype  approach.     • The  typicality  effect  may  occur  because  a  person  has  encountered  specific  exemplars  and   thus  is  quicker  to  identify  them  as  belonging  to  the  category.  In  addition,  birds  that  are   closer  to  an  exemplar  are  more  likely  to  be  classified  quicker;  for  example  a  cardinal  versus   a  penguin.       Recall  that  the  prototype  approach  compares  objects  to  the  “average”  (prototype)  member  of  the   category.  The  exemplar  approach  has  the  following  advantages:   • It  takes  into  account  atypical  qualities.  Rather  than  comparing  to  an  average  member  of  the   category  (the  prototype),  atypical  objects,  such  as  a  flightless  bird,  can  be  categorized.     • It  allows  for  more  variability.  How  do  you  have  an  average  game  when  you  have  to  factor  in   football,  computer  games,  marbles,  solitaire,  golf,  etc?  The  exemplar  approach  only   requires  that  some  of  these  games  are  remembered  as  examples  of  a  game  in  order  to  be   quickly  sorted  into  the  category.       The  prototype  and  exemplar  approaches  are  really  similar  sounding.  It  is  generally  accepted  that   humans  use  both  methods.  The  prototype  approach  is  first  used  when  we  know  little  about  a   category,  and  the  more  when  learn  and  expand  the  schema  we  move  to  the  exemplar  approach  to   accommodate  exceptions.  The  prototype  approach  is  more  common  with  small  categories,  such  as   “U.S.  Presidents”  or  “Mountains  over  15,000  feet”  but  the  exemplar  approach  is  used  more  for   large  categories  such  as  “birds”  or  “automobiles.”       An  example  that  provides  a  quick  distinction  between  prototypes  and  exemplars:  we  know  what   cats  are  (prototype)  but  we  know  our  own  cat  best  (exemplar).       Hierarchical  organization:  method  used  to  organize  categories  from  subcategories.  See  picture.         Rosch  claimed  that  the  basic  level  is  “psychologically  privileged.”  When  asked  to  list  features   common  to  the  global  level  of  furniture,  there  are  an  average  of  3  common  traits.  Items  at  the   basic  level  had  an  average  of  9  common  traits,  and  at  the  specific  level  there  was  an  average  of   10.3  traits.  The  basic  level  is  privileged  because  going  more  general  causes  a  huge  loss  in   information  and  going  more  specific  gives  little  additional  information.       3   PSYC  221  –  Knowledge     A  simple  demonstration  of  how  we  prefer  the  basic  level:  look  at  the  following  photo  and  quickly   name  the  items.       I  said  guitar,  fish,  and  pants.  Although  I  could  have  chosen  the   global  or  specific  level  I  preferentially  chose  the  basic  level  when   quickly  naming.     • Instrument  à  Guitar  à  Electric  guitar   • Animal  à  Fish  à  Rainbow  trout   • Clothing  à  Pants  à  Blue  jeans     The  level  that  takes  precedence  is  not  the  same  for  everyone.  Participants  were  shown  various   pictures  and  were  asked  to  name  what  the  picture  was  of.  There  were  four  bird  pictures  that  the   researchers  were  interested,  and  the  rest  of  the  photos  served  as  controls.  When  nonexperts  saw   the  bird  photos  they  said  “bird.”  When  experts  saw  the  bird  photos  they  noted  the  species.  The   same  has  been  demonstrated  with  experts  and  nonexperts  of  plants.  This  demonstrates  that  the   layman  may  prefer  the  basic  level,  but  people  with  much  interest  or  expertise  may  attend  to  the   more  specific  features  and  choose  this  subordinate  level.       How  are  categories  arranged  in  the  mind?     Semantic  network  approach:  concepts  are  arranged  in  hierarchical  networks.  It  is  hierarchical   because  information  is  represented  at  different  levels  of  specificity.               To  the  left  is  the  Collins  &  Quillian  model   of  a  semantic  network.                       Cognitive  economy:  properties  that  are  shared  by  many  members  of  a  categ
More Less

Related notes for PSYC 221

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.