CHAPTER 11
Action Selection
ROBERT W. PROCTOR AND KIM-PHUONG L. VU
293FUNDAMENTAL ISSUES, MODELS, AND THEORIES 294
Historical Background 294
Methodological and Modeling Issues 295
Discrete and Continuous Models of Information
Processing 296
Speed-Accuracy Trade-Off 297
Psychophysiological Measures 297
RELEVANT STIMULUS INFORMATION 298
Uncertainty and Number of Alternatives:
The Hick-Hyman Law 298
Stimulus-Response Compatibility 299
Sequential Effects 301
Advance Information 303
RELEVANT AND IRRELEVANT STIMULUS
INFORMATION 304
Noncorrespondence of Relevant and
Irrelevant Information 304
Negative Priming 306
MULTIPLE TASKS 307
Task Switching 307
Psychological Refractory Period 308
Stop Signals 309
CHANGES IN ACTION SELECTION WITH PRACTICE 310
APPLICATIONS 310
SUMMING UP 312
REFERENCES 312Action selection refers to how a decision is made, typically
under speeded response conditions, regarding which of two
or more actions to take in response to perceptual events. It is
usually studied using choice-reaction tasks in which subjects
make assigned responses to stimuli as quickly and accurately
as possible, and reaction time (RT) and response accuracy are
measured. Action selection is often called response selection,
but the term action selectionhas come to be used more fre-
quently in recent years to emphasize that responses in choice-
reaction tasks are goal-directed actions (Prinz, 1997).
A recent example of the importance of action selection
concerns the notorious butterfly ballot used in Palm Beach
County, Florida, for the 2000 U.S. presidential election. The
ballot, shown in Figure 11.1, listed the names of candidates in
two columns, with the appropriate response being to insert a
stylus into a punch hole assigned to the candidate of choice
among a centered column of holes. Although there was no
fixed time limit for responding, the voters’ task was speeded
in the sense that a limited number of voting booths were
available, with many voters needing to use them. With this
ballot, some voters apparently selected the second punch hole
on the list, voting for Pat Buchanan, rather than the third
punch hole, which was assigned to Al Gore, for whom they
intended to vote. This selection error occurred because Gore
was listed in the second position of the left-hand column, im-
mediately below the major opposing candidate, George W.
Bush. Punch ballots most often list all candidates on the left-
hand side, and their corresponding punch holes in the same
order on the right. Because the relative location of Gore’s po-
sition in the left-hand candidate list was second, previous ex-
perience would lead voters to expect that the second hole
should be punched to vote for him. Moreover, this expectancy
is consistent with the general principle that people tend to
make the response whose relative location corresponds to that
of the stimulus. Consequently, it is not surprising that some
voters would incorrectly punch the second hole instead of the
third one, even though arrows were used to mark the desig-
nated punch holes for the candidates. The poor design of the
ballot caused a sufficient number of unintended votes for
Buchanan, as well as discarded ballots for which the second
and third holes were punched, costing Gore the election.
As this example illustrates, the topic of action selection is
undoubtedly important. However, action selection tends to
be viewed as peripheral to mainstream cognitive psychology
in the United States, as reflected in the fact that the topic
is rarely mentioned in undergraduate cognitive psychology