Simons & Chabris (1999) Flashcards
Theories on which Simons and Chabris’ study is based?
Driver (1996) - focussed visual attention
Rensink at al (1997) - change blindness
Mack and Rock (1998) - inattention blindness
Fisher (2007) - harder you concentrate, less likely your are to be distracted
theories of divided attention:
Kahneman - limited capacity theory
Allport, Eysenck, Bandely - multi-channeltheories
Schneider and Shiffrin - automaticity model
Norman and Shallice - SAS (supervisory attentional system) model
Background to Simons and Chabris’ study?
Becklen Cervone (1983) + Stroffregen and Becklen (1989) - observers did not see unexpected event clearly visible to others not engaged in concurrent task
goal = revive empirical approach
info on intentional blindness from Mack and Rock (1998) + Rubin and Hua (1998)
info on selective looking from Neisser and Becklen (1975) , Becklen, Neisser and Littman (1979), Becklen and Cervone (1983) + Stoffregen et al (1993)
previous research did not consider task difficulty or compare performance with superimposed version with live version of event
Simons and Chabris research method?
lab experiment
controlled observation - participants watched diff vid, test condition white easy
Simons and Chabris design?
independent measures
Simons and Chabris IVs?
transparent umbrella woman
opaque umbrella woman
transparent gorilla
opaque gorilla
Simons and Chabris test conditions?
white easy
white hard
black easy
black hard
Simons and Chabris DV?
number of participants who noticed unexpected event
Simons and Chabris materials?
4 videos, 75 secs
2 teams of 3 players
players moved around randomly in front of 3 lifts
passed basketball in standardised order
bounce and arial passes
players dribble ball, wave arms etc
after 44-48 secs - unexpected event lasting 5 secs
transparent condition - white team, black team + unexpected event filmed separately, made to be partially transparent then superimposed
opaque - all filmed together
another opaque video - gorilla faced camera + thumped chest
Simons and Chabris sample?
192 (originally 228 - 36 discarded)
almost all undergraduate students
volunteer sample
no compensation, large candy bar or paid single fee
controlled observation - 12 watched gorilla thumping chest video
Simons and Chabris procedure?
21 experimenters - written protocol reviewed with them - standardisation
participants tested individually
informed consent
vid ended - participants asked to write down counts for easy and hard tasks
Qs:
While you were doing the counting, did you notice anything unusual in the video?
Did you notice anything other than the six players?
Did you see a gorilla / woman carrying an umbrella walk across the screen?
asked if previously participated in similar experiment, heard of experiment, heard of general phenomenon - yes - data discarded
debriefed
5-10 mins
Simons and Chabris key findings? overall opaque transparent easy hard transparent easy VS transparent hard opaque say VS opaque hard umbrella woman VS gorilla gorilla - black VS white umbrella woman - black VS white
overall - 54% noticed unexpected event
opaque - 67% noticed
transparent - 42% noticed
easy - 64% noticed
hard - 45% noticed
transparent easy VS transparent hard - 56% VS 27%
opaque easy VS opaque hard - 71% VS 62%
umbrella woman VS gorilla - 65% VS 44%
gorilla - black VS white - 58% VS 27%
umbrella woman - black VS white - 62% VS 66%
controlled observation - 50%
Simons and Chabris possible conclusions?
dynamic events - sustained inattentional blindness
primary monitering task - don’t notice unexpected event
inattentional blindness = perceptual phenomenon
harder primary task - inattentional blindness higher
unexpected event similar to what you are paying attention to - more likely to notice
objects can pass through space where attention focussed and not be seen
no conscious perception without attention
