Paper 2 - Simons and Chabris on Visual Attention Flashcards
what were the aims of the study ?
build on previous research to investigate the effect of visual similarity, task difficulty, superimposed vs live version and nature of the unusual event on visual detection rates.
what was the method desin of this study ?
- lab experiment
- independent measures design
- there were 16 conditions
1. if the unexpected event was a gorilla or an umberalla woman
2. if the film was transparent or opaque
3. if the task was easy or hard
4. if the pps followed the black or white team
what was the sample of this study
- a self selected sampe of 228 mainly undergraduates from an american uni who acted as observers
- some were given a reward like candy or a small fee.
- in the final analysis only 192 pps were used.
- the remianing 36 pps knew about the theory before so there results were ignored
- 12 took part in a controlled observation
what were the materials
- 4 videotapes of 2 teams throwing a basketball each video tape lasted for 45 seconds, had 2 teams with 3 players each, showed players passing the ball in an order from player 1 to player 3.
- after 44 seconds an unexpected event occurs lasting for 5 seconds; a woman with an umberella or a gorilla suite walking from the left to the right.
- there were 2 types of videos: transparent (actors superimposed) or imposed (actors filmed at the same time)
what was the procedure of this study ?
- all pps were tested individually and took part on 1 of the 16 conditions
- pps were told to watch either the black or white team, also they were told to keep a silent mental count of either the total number of passes made by their team, or the total numbe rof bounce passes and air passes made by their team.
- immediately after they were made to write down their count
- there was a surprise series of questions: ‘did you notice anything unusual on the video?’, ‘did you see anyone else?’
- if they said yes they were asked for details.
- pps were aksed if they had ever previously participated in an experiment similar to this or had ever heard of such an experiment, or the general theory, if they said yes their data was discarded.
what were the results for this experiment ?
- 54% of pps noticed the unexpected event.
- the umberalla woman was noticed 65% versus 44% for the gorrilla suit.
- when the unexpected event was the gorilla, pps watching the black team noticed the gorrila more then those following the white team ( 58% vs 27%).
- the event was noticed more in the easy condition 64% vs 42%.
- in the controlled observation, only 50% noticed the event.
what are the conclusions of this study
- observers are less likely to notice the unexpected event if these events are visually dissimilar to the events they are paying attention to.
- even when the unexpected object passes through the area of focus in the eye it may be undetected
- this shows that there is no conscious perception without attention
evaluate the method used
- lab experiment means that there is a high control of extraneous variables. high internal validity and high reliability.
- however it lacks ecological validity
- independent measures design - more pps variables but less order effects
evaluate the ethics
- pps were debriefed which included replaying the videotape.
- they gave infromed consent
- there may be deception about what they were supposed to be paying attention to
evaluate the sample
- the population is large but there were 16 conditions so 12 in ecah condition which is a small sample
- low population validity as they were students so they may have higher cognitive ability than the average population
- self selected sampling allowed for motivated pps who are less likely to drop out.
evaluate the ethnocenrism
- previous research found the asian students focus on periphery details rather than central details, it is the opposite for us students.
- the study was only done on american students so the sample is ethnocentric.
evaluate the data
- quantitative data is objective and easy to analyse so comparisons can be made.
- no qualitative data means there is no detailed explanation by the pps.
What is the background to this study ?
- Mack and Rock - observers shown a cross and asked to focus on the arms of the cross. An unexpected event occurred.
- Neisser- observed asked to focus on people handslapping. unexpected events occurred
- Neisser - observed asked to focus on people passing a ball, a woman carrying an umbrella walks across the video.
- All studies are similar to simon and chabris as they illustrate selective attention and inattentional blindness, as the observers failed to notice the unexpected event.
how is this study useful
understanding the circumstances that attention is lost or gained and how to avoid losing attention with the potential to reduce the number of accidents and save lives.
what debates and perspectives does this study relate to
- against the psychodynamic perspective - we cannot consciously percieve something without paying attention to it.
- determinism - factors beyond our consciousness control may dictate our perceptions.
- freewill - we can consciously focus out attention if necessary