Read The Invisible Gorilla: And Other Ways Our Intuitions Deceive Us Online
Authors: Christopher Chabris,Daniel Simons
51.
Wolfe et al., “Rare Items Often Missed.”
52.
For a brief discussion, see T. Griffiths and C. Moore, “A Matter of Perception,”
Aquatics International
, November/December 2004 (
www.aquaticsintl.com/2004/nov/0411_rm.html
).
53.
Examples of GPS-induced accidents come from the following sources: “Driver Follows GPS into Sand,” Reuters, October 10, 2006 (
www.news.com.au/story/0,23599,20555319-13762,00.html
,);
“Train Hits Car, and a G.P.S. Is Blamed,” Associated Press, October 1, 2008 (
www.nytimes.com/2008/10/01/nyregion/01gps.html
); T. Carey, “SatNav Danger Revealed: Navigation Device Blamed for Causing 300,000 Crashes,” July 21, 2008 (
www.mirror.co.uk/news/top-stories/2008/07/21/satnavdanger-revealed-navigation-device-blamed-for-causing-300-000-crashes-89520-20656554/
); “Lorry Driver Had to Sleep in Cab for Three Nights After Sat-Nav Blunder Left Him Wedged in Country Lane,”
Daily Mail
, November 1, 2007 (
www.dailymail.co.uk/news/article-491073/Lorry-driver-sleep-cab-nights-sat-navblunder-left-wedged-country-lane.html
); “Sat-Nav Dunks Dozy Drivers in Deep Water,”
The Times (London) Online
, April 20, 2006 (
www.timesonline.co.uk/tol/news/article707216.ece
). The ford in this last example is normally about two feet deep.
1.
Many of the details and quotes for the Bobby Knight/Neil Reed story are taken from an article entitled “A Dark Side of Knight,” first published on the CNN/Sports Illustrated website on March 18, 2000, updated September 10, 2000. The article was intended to expose some of the vulgar and abusive antics Knight exhibited during practices, with the implication that his behavior had caused the players to leave. However, the story acknowledged that Knight’s program had no more departures than other top college basketball programs. Some students who left the program, like Richard Mandeville, regretted not doing so sooner. Other players, like Alan Henderson—who stayed in the program, graduated, and became a top shooting guard in the NBA—spoke more fondly of Knight’s motivational techniques. Henderson admitted that Knight had been a tough coach who “got on me sometimes like he got on everybody,” but praised him for his desire to improve his players and his generosity and willingness to help. Other quotes were taken from the following CNN/Sports Illustrated articles: “Defending ‘The General,’” April 12, 2000; and “The Knight Tape,” September 9, 2000. Biographical details on Bobby Knight are drawn from the National Basketball Association Hoopedia blog, hoopedia.nba.com/index.php?title=Bob_Knight, and from Wikipedia, en.wikipedia.org/wiki/Bob_Knight (both accessed June 29, 2009). Many of the incidents from Knight’s career are documented in “Bob Knight’s Outburst Timeline,”
USA Today
, November 14, 2006.
2.
As we mentioned in a note to Chapter 1, our items were designed to present beliefs that the scientific consensus regards as false, so an ideal rate of agreement would be 0 percent. We also found that 83 percent of people believe that amnesia, or sudden memory loss, results in the inability to recall one’s name and identity. This belief may reflect the way amnesia is usually portrayed in movies, television, and literature. For example, when we meet Matt Damon’s character in the movie
The Bourne Identity
, we learn that he has no memory for who he is, why he has the skills he does, or where he is from. He spends much of the movie trying to answer these questions. But the inability to remember your name and identity is exceedingly rare in reality. Amnesia most often results from a brain injury that leaves the victim unable to form
new
memories, but with most memories of the past intact. (Some movies do accurately portray this more common syndrome, known as “anterograde” amnesia; our favorite is
Memento.)
3.
This pattern of recall is known as the
serial position curve
. This “U-shaped” curve
(better recall of items from the beginning and end of a list than from the middle of the list, hence the U-shaped function) is one of the best-established findings in the literature on memory function; see H. Ebbinghaus,
Memory: A Contribution to Experimental Psychology
, trans. H. A. Ruger and C. E. Bussenius (New York: Columbia University, 1885/1913). For evidence of a serial position curve with this particular type and length of list, see H. L. Roediger III and K. B. McDermott, “Creating False Memories: Remembering Words Not Presented in Lists,”
Journal of Experimental Psychology: Learning, Memory, and Cognition
21 (1995): 803–814.
4.
Evidence for a seven-item limit on short-term memory comes from G. A. Miller, “The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information,”
Psychological Review
63 (1956): 81–97. Evidence that children lack adult memorization skills comes from J. H. Flavell, A. G. Friedrichs, and J. D. Hoyt, “Developmental Changes in Memorization Processes,”
Cognitive Psychology
1 (1970): 324–340. This study shows that preschool children also think they will remember more than they actually do. Primary school students also overestimate their memory abilities, but not nearly as much as preschoolers.
5.
J. Deese, “On the Prediction of Occurrence of Particular Verbal Intrusions in Immediate Recall,”
Journal of Experimental Psychology
58 (1959): 17–22; Roediger and Mc-Dermott, “Creating False Memories.”
6.
The study was described in the following article: W. F. Brewer and J. C. Treyens, “Role of Schemata in Memory for Places,”
Cognitive Psychology
13 (1981): 207–230. Some of the earliest demonstrations that memory encodes meaning in the form of associations with what we already know come from this classic: F. C. Bartlett,
Remembering: A Study in Experimental and Social Psychology
(Cambridge: Cambridge University Press, 1932).
7.
“The Knight Tape,” CNN/Sports Illustrated, September 9, 2000.
8.
This quote is also from CNN/Sports Illustrated’s report “The Knight Tape.”
9.
Increased wait times have become more common with increased use of cell phones and decreased numbers of operators. For example, in Las Vegas in 2002, only 65 percent of calls were answered within the national standard of ten seconds (A. Packer, “Metro 911 Calls Often Put on Hold,”
Las Vegas Sun
, October 23, 2004). At the two largest call centers in Los Angeles and San Francisco, average wait times are more than fifty seconds, and in some extreme cases, callers had to wait more than ten
minutes
for an operator (R. Lopez and R. Connell, “Cell Phones Swamping 911 System,”
The Los Angeles Times
, August 26, 2007).
10.
Chris learned of the incident in a conversation with the witnesses on May 30, 2008. He asked them not to talk about it further before he could interview each of them separately. The interview with Leslie Meltzer took place by telephone on August 5, 2008; the interview with Tyce Palmaffy took place by telephone on December 30, 2008.
11.
Different people have different roles on a movie set, and each may notice elements related to his or her area of focus. Costumers might notice changes to clothing, cinematographers focus on lighting changes, etc. The script supervisor is the one person responsible for trying to make sure all the important details match across shots. See A. Rowlands,
The Continuity Supervisor
, 4th ed. (Boston: Focal Press, 2000); P. P. Miller,
Script Supervising and Film Continuity
, 3rd ed. (Boston: Focal Press, 1999).
12.
At the time of this writing, a Google search for “film flubs” turns up more than thirty-five hundred hits.
13.
“Film Flubs: Mistakes Made and Left in Popular Movies,”
Dateline NBC
, March 22, 1999.
Saving Private Ryan
won the Academy Award for editing in 1998 and
Shakespeare in Love
was nominated that same year (see awardsdatabase.oscars.org). Mankiewicz also assumed that the filmmakers were unaware of the errors. Script supervisor Trudy Ramirez told Dan in an interview on June 6, 2009, “The amount of handling and viewing and the numbers of people that are involved in the post-production process and in the editing is so extensive, that for something to literally get through with every one of those people being unaware is highly unlikely. I don’t know how many times it’s happened, if ever. A number of people would have discussed the merits of utilizing the shot with an error prior to it ending up in the film.” In other words, they might have needed a shot of soldiers walking across a field, but they didn’t have one with seven soldiers, so they decided to use the one with eight soldiers despite the error. The facts about
The Godfather
and
Spartacus
come from the Internet Movie Database,
www.imdb.com/title/tt0068646/goofs
;
www.imdb.com/title/tt0054331/goofs
(both accessed November 14, 2009).
14.
D. T. Levin and D. J. Simons, “Failure to Detect Changes to Attended Objects in Motion Pictures,”
Psychonomic Bulletin and Review
4 (1997): 501–506. You can view the film at
www.theinvisiblegorilla.com
.
15.
Subjects answering yes were then asked to describe the changes they noticed. Only one subject reported noticing anything, and that person’s description was sufficiently vague that it was not clear whether the individual had actually noticed a change.
16.
The term “change blindness” was coined in this article: R. A. Rensink, J. K. O’Regan, and J. J. Clark, “To See or Not to See: The Need for Attention to Perceive Changes in Scenes,”
Psychological Science
8 (1997): 368–373.
17.
The term “change blindness blindness” and the data described in this paragraph come from: D. T. Levin, N. Momen, S. B. Drivdahl, and D. J. Simons, “Change Blindness Blindness: The Metacognitive Error of Overestimating Change-Detection Ability,”
Visual Cognition
7 (2000): 397–412. Of 300 subjects, 76 percent predicted they would notice the change to the plates, and 90 percent of 297 subjects predicted they would notice the change to the scarf.
18.
These quoted responses are taken from an unpublished replication of the earlier studies (which were done at Cornell by the two Dans) that Dan conducted while he was at Harvard. They are typical of responses written by subjects in all of these change blindness experiments. Levin and Simons (“Failure to Detect Changes to Attended Objects”) found that across four different pairs of actors performing two different simple actions, approximately two-thirds of the subjects failed to report any change. For the particular video described in the text, none of the subjects in the original experiment reported the change.
19.
See Levin and Simons, “Failure to Detect Changes to Attended Objects.” A video of a subject participating in this study can be viewed at
www.theinvisiblegorilla.com
.
20.
Script supervisors have many responsibilities on set, including keeping track of all the details of each take (e.g., the cameras used, what actors said, how the action progressed, how long the shot was, etc.). Their extensive notes guide the entire postproduction process.
21.
Quotes from Trudy Ramirez are from an e-mail correspondence on June 2–6, 2009, and a telephone interview with Dan on June 6, 2009. Dan also corresponded with a second script supervisor, Melissa Sanchez (on November 14, 2004, and June 2–3, 2009), who was tremendously helpful in guiding our writing of this section.
22.
Two of the best-known training manuals for script supervisors,
Script Supervising and Film Continuity
by Pat Miller and
The Continuity Supervisor
by Avril Rowlands, give advice that is entirely consistent with what Trudy Ramirez said: Don’t count on your ability to remember visual details. Miller, who advises readers to take photographs and copious notes, recognizes the limits of memory: “It is humanly impossible and patently unnecessary for you to simultaneously watch and note every detail in a scene. The mark of a competent continuity supervisor is not so much the possession of extraordinary powers of observation … but your confidence in knowing what is important to observe” (p. 177). Rowlands agrees: “… it is
what
you notice that is important. You will never notice everything that is happening within a shot and it is not necessary that you should, providing the things you
do
notice and write down are those which are important in order to preserve continuity” (p. 68).
23.
Of 108 undergraduates, 98 percent predicted they would notice the person change (Levin et al., “Change Blindness Blindness”).
24.
D. J. Simons and D. T. Levin, “Failure to Detect Changes to People During a Real-World Interaction,”
Psychonomic Bulletin and Review
5 (1998): 644–649.
25.
This experiment is described in D. T. Levin, D. J. Simons, B. L. Angelone, and C. F. Chabris, “Memory for Centrally Attended Changing Objects in an Incidental Real-World Change Detection Paradigm,”
British Journal of Psychology
93 (2002): 289–302. A demonstration of the experiment was broadcast on the BBC program
Brain Story
and was also re-created on
Dateline NBC
in 2003.
26.
For an overview of the evidence for change blindness, see D. J. Simons and M. Ambinder, “Change Blindness: Theory and Consequences,”
Current Directions in Psychological Science
, 14 (2005): 44–48.
27.
Simons and Levin, “Failure to Detect Changes to People.” The studies in which we changed the race or sex of the actor have not yet been published. We conducted one study in which we replaced a male actor with a female actor in the counter paradigm mentioned earlier, and nobody missed the change. Dan and his former graduate student Stephen Mitroff also conducted a series of video-based change detection experiments in which the race or sex of an actor was changed. Again, nobody missed these changes.