Simon and Chabris (1999) Flashcards
What is the full name of this study?
Simons & Chabris (1999) Gorillas in our midst: sustained in-attentional blindness for dynamic events
What does this study build upon?
classic studies of divided visual attention to:
- examine inattentional blindness for complex objects and events in dynamic scenes
What did previous studies fail to do?
- not systematically consider the role of task difficulty in detection
- no direct comparisons made between performance and superimposed version of the display with a live version
How did this study aim to correct past failures?
- several video segments
- same set of actions
- same location
- same day
What is an overview of this study?
- large number of naïve participants watched video recordings
- later answer questions about unexpected event
What is the sample?
- 228 participants = ‘observers’
- undergraduates
- volunteers
What is a strength of the sample?
large = more representative = population validity = generalisable
What is a weakness of the sample?
36 participants were removed = 192 as the sample
What is the sampling technique?
self-selected (volunteer)
What is a strength of volunteer sampling?
easy to obtain
What is a weakness of volunteer sampling?
only a certain type of person volunteers = not as representative or generalisable
What were the participants given as a reward for participating?
either a large candy bar or paid a single fee
What is a strength of offering a reward?
gives incentive to stay and complete the study - less chance of attrition
What is a weakness of offering a reward?
participants may not feel like they have the right to withdraw
What was the sample for the controlled observation?
12
What was the controlled observation?
the video where the gorilla thumps its chest
What was the method used for this study?
laboratory experiment
What is a strength of the method?
- high control over extraneous variables = more valid results
What is a weakness of the method?
- lacks ecological validity
- lacks mundane realism
What is the design?
independent measures
What are the strengths of the design?
- less chance of order effects
- less chance of demand characteristics
What are the weaknesses of the design?
more participants are needed
What are the 4 IVs?
1- Transparent/umbrella
2- Transparent/gorilla
3- Opaque/umbrella
4- Opaque/gorilla
What are the 4 task conditions?
1- White/Easy (passes by white shirts)
2- White/Hard (bounce or aerial passes by white shirts)
3- Black/Easy (passes by black shirts)
4- Black/Hard (bounce or aerial passes by black shirts)
How many conditions are there total?
16
What is the DV?
noticing the unexpected event
What type of media was used in this study?
- videotapes
- 4
- 75 seconds each
- filmed using SVHS
What did each tape have in common?
- 2 teams
- 3 players each (6)
- white shirts vs. black shirts
What apparatus was used?
a standard orange basketball
Where did the videos get filmed?
in front of 3 elevator doors
What was the standardised passing order?
1-2-3-1-2-3-1
What type of movements were often displayed?
- bounce or aerial passes
- dribbling
- moving arms
- other movements of a similar fashion
What was the purpose of the movement of the players?
to mimic stimuli from previous research
When in the videos did the unexpected event occur?
44-48 seconds in
How long did the unexpected event last?
5 seconds
What was the unexpected event in one condition?
- umbrella
- tall woman
- left to right
What was the unexpected event in the other condition?
- gorilla costume
- short woman
- covered whole body (by costume)
- left to right
What was the separate video also filmed?
- gorilla event
- right to left instead
- opaque
What were the two styles of video?
opaque and transparent
How were the transparent videos filmed?
- all parts filmed separately
- superimposed through editing software
- non-linear editing software
How were the opaque videos filmed?
- simultaneously
- rehearsal was needed
Why was rehearsal needed for the opaque videos?
- eliminate collisions
- making the patterns of movement appear natural
How many experimenters were there?
21
Why were there so many experimenters?
to ensure standardisation = more reliable
How were participants tested?
individually
What ethical issue was addressed at the start of the study?
informed consent
What were participants told before they watched the video?
- an outline of what the video is eg., a video of 6 people 3 in white shirts and 3 in black passing a basketball
- who to focus on e.g., the white shirts and how many passes
What were participants told to do?
- keep a mental count of passes (easy con) or aerial and bounce passes (hard con)
- write down amount they counted on paper immediately after
What were participants asked after they watched the video?
3 surprise questions
What were some of the surprise questions?
1- did you notice anything unusual?
2- anything other than the 6 players?
3- [unexpected event]?
Why were some participants details omitted?
- already aware of the phenomenon
- lost count of passes
- inaccurately counted passes
What are some general findings?
- 54% noticed the unexpected event
- more noticeable in the opaque condition
- 33% failed to report the unexpected event
- transparent condition harder
- umbrella woman was noticed more than the gorilla
What are some specific findings?
- noticed gorilla more when watching black team = 58% vs. 27%
What are the findings of the controlled observation?
- 50% noticed the unexpected event
What are the conclusions of this study?
- individuals are more likely to notice an event if they are visually similar
- individuals have sustained inattentional blindness for dynamic events
