Cognitive Enhancement Through Stimulation of
the Chemical Senses
Phillip R. Zoladz and Bryan Raudenbush
Wheeling Jesuit University
Finding a non-pharmacological adjunct to enhance cognitive processing
in humans would be beneficial to numerous individuals. Past research has
consistently noted a significant interplay between odors and human
behavior; for example, the administration of particular odorants enhances
athletic performance, mood, and sleep quality. In addition, odorants have
a differential effect on human behavior, dependent upon route of
administration (retronasal vs, orthonasal). The following study examined
the differential effects of odoranis on cognition based upon route of
administration. During Phase I, 31 participants completed cognitive tasks
on a computer-based program (Impact®) under five "chewing gum"
conditions (no gum, flavorless gum, peppermint gum. cinnamon gum,
and cherry gum). During Phase 11, 39 participants completed the
cognitive tasks under four odorant conditions (no odor, peppermint odor,
jasmine odor, and cinnamon odor). Results revealed a task-dependent
relationship between odors and the enhancement of cognitive processing.
Specifically, cinnamon, administered retronasally and orthonasally,
improved participants' scores on tasks related to attentional processes,
virtual recognition memory, working memory, and visual-motor response
speed. Implications are discussed in relation to providing a nonpharmacological adjunct to enhance cognition in the elderly, individuals
with test-anxiety, and those with symptoms of dementia.
Finding a non-pharmacological adjunct to enhance cognitive
processes in humans would be both groundbreaking and readily accepted
by society. Attempting to enhance cognitive processing by such measures
could ultimately reduce a person's perceived cognitive effort for a task,
while still allowing for an enhancement of his or her overall performance
on that task.
Since pleasant odors induce positive affective reactions, some have
argued that the mere presence of such odors may also lead to cognitive,
social, psychological, physiological, and physical
performance
enhancements, and evidence does exist to support this position. For
example, Knasko (1992) found that a lemon odor led to fewer reports of
health symptoms, and Rottman (1989) noted that jasmine odor enhanced
individuals' performance on problem-solving tasks and led the
Author info: Correspondence should be sent to: Dr, Bryan Raudenbush, Wheeling
Jesuit University, Dept. of Psychology, 315 Washington Ave., Wheeling, WV
26003. E-mail at raudenbc@wju.edu.
North American Journal ofPsychology,2005,Vo\. 1,"No. 1, 125-140.
©NAJP
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NORTH AMERICAN JOURNAL OF PSYCHOLOGY
participants to indicate higher levels of interest and motivation to the
task. Raudenbush, Koon, Meyer, and Flower (2002a) found that
peppermint odor reduced ratings of pain over time and increased
participants' overall pain tolerance, as measured by a cold pressor test.
Participants also reported reduced mental, physical, and temporal
workload requirements, lower effort and frustration, and increased
performance and vigor in the presence of peppermint odor. Peppermint
odor significantly increased oxygen saturation and blood pressure,
providing evidence for its ability to physiologically arouse the human
body. Raudenbush, Meyer, and Eppich (2002b) found that during a
treadmill stress test peppermint odor reduced measures of workload,
effort, fatigue, and frustration, while increasing self-evaluated
performance and vigor. Raudenbush, Corley, and Eppich (2001) found
peppermint odor increases running speed, handgrip strength, and the
number of push-ups performed during a physical workout session.
Despite the numerotis reports that support the notion of odorenhanced performance, however, some research has revealed the
converse. For instance, research has shown that the presence of a
pleasant lavender odor significantly undermines the performance of
working memory, reaction time for memory and attention based tasks,
and arithmetic reasoning (Ludvigson & Rottman, 1989; Moss, Cook,
Wesnes, & Duckett, 2003). Thus, it would seem that it is not the mere
presence of a pleasant odor that enhances performance, but rather
something specific to the odorant itself.
Recent research has compared the effects of orthonasal and retronasal
odorants on human behavior. According to Pierce and Halpem (1996),
stimuli arrive at the olfactory epithelium through two distinct pathways:
an orthonasal stimulus travels inward through the naris towards the
olfactory mucosa, while a retronasal stimulus travels via the mouth to the
nasopharynx. While Raudenbush, et al. (2002h) found that an orthonasal
administration of peppermint odor significantly enhanced athletic mood,
performance, and workload, Zoladz, Raudenbush, Fronckoski, and Price
(2003) did not replicate such fmdings when using a retronasal
administration of the same odor. Since research has shown that it is easier
for an odorant to affect human behavior if it is administered orthonasally
(Puttanniah & Halpem, 2001), the effects odorants have on human
behavior appears to be partially dependent upon the route by which they
are administered.
The following experiments were designed to assess tiie effects of
retronasal (Phase I) and orthonasal (Phase II) odorant administration on
cognition. In Phase I, participants completed multiple cognitive tasks
under five retronasal odorant (via chewing gum) conditions (peppermint
gtim, cirmamon gum, cheny gum, flavorless gum, and no gum). In Phase
Zoladz & Raudenbush
COGNITIVE ENHANCEMENT THROUGH
127
n, participants completed multiple cognitive tasks under four orthonasal
odorant conditions (peppermint odor, cinnamon odor, jasmine odor, and
no odor). Participants also con:q)leted questionnaires assessing meastires
of mood and workload. It was hypothesized that orthonasal odorant
administration would have a greater impact on cognitive performance.
Given the fmdings of past research, the administration of peppermint
odor was expected to increase individuals' alertness and attention,
ultimately enhancing their cognitive performance.
PHASE I: RETRONASAL
Chewing flavored gum facilitates episodic and working memory in
humans (Wilkinson, Scholey, & Wesnes, 2002). Sesay, Tanaka, Ueno,
Lecaroz, and De Beaufort (2000) report that mastication alone improves
regional cerebral blood flow, and Yagyu, Kinoshita, Hirota, Kondakor,
Koenig, Kochi, and Lehmann (1998) suggest that the chewing of
flavored vs, non-flavored gum activates different neuronal populations in
the brain. Most importantly, Morinushi, Masumoto, Kawasaki, and
Takigawa (2000) showed that the specific flavor of gum, in addition to
mastication, increases brain activity.
Method
Participants. Participants were 31 young adult volunteers (13 males,
18 females, mean age = 20.19 years) obtained through convenience
san^ling. Participants were students in a variety of psychology classes
and were awarded course credit.
Stimuli. Gum stimuli consisted of peppermint (Wrigley's Extra*
Peppermint), cinnamon (Wrigley's Big Red®), cherry (Fruit Stripe®), and
flavorless gum (gum base).
Cognitive Performance Software. The Impact® software was used to
measure a variety of aspects of participants' cognitive performance and
functions (see Appendix A). Internal reliability for this instrument ranges
from .88 to .94 in various san^les, with test-retest reliability of .80
(Iverson, Lovell & Collins, 2002; Iverson, Lovell, Collins, & Norwig,
2002).
Procedure. Participants were briefed as to the nature of the study,
produced written consent, and provided demographic infonnation. They
then began chewing a piece of gum (cinnamon, peppermint, cherry, or
flavorless) for five minutes prior to the cognitive assessment, or, in the
control condition, sat quietly for five minutes instead of chewing gum.
After five minutes had elapsed, participants completed the Impact® test,
with those participants in the gum conditions continuing to chew the gimi
throughout the duration of testing.
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NORTH AMERICAN JOURNAL OF PSYCHOLOGY
The protocol was completed five times in a repeated measures design
with each participant exposed to each condition, and with each condition
separated by at least 24 hours. The order of the conditions was randomly
assigned, and each session lasted approximately 45 minutes. The Impact
test has five different versions of each sub-test, which limited practice
effects.
Results
Cognitive Performance Scores. One-between (sex), two-within
(cognitive task, gum condition) ANOVAs were performed to compare
cognitive scores for tasks on the Impact® test. One-within (gum
condition) ANOVAs were performed to compare composite scores of
verbal memory, visual memory, visual motor speed, reaction time, and
impulse control in the gum conditions. Alpha was set at .05, and Tukey
HSD Post-hoc contrasts were performed to determine the direction of
effects.
Design Memory Task. A trend was found for gum condition, Ftuf, =
2.361, p = .OSl. Greater design memory scores were found in the
TABLE 1 Means and Standard Errors for the Cognitive Performance
Scores in Phase I
Task
Word
Discrimination
Design
Memory
X's and O's
Symbol
Matching
Color Match
Three Letters
Verbal Mem.
Composite
Visual Mem.
Composite
Visual Motor
Speed Comp.
Reaction Time
Composite
Impulse Cont.
Composite
No Gum
45.89
(.64)
33.19
(1.00)
29.03
(.33)
9.16
(-11)
2.50
(.03)
24.93
(.48)
86.68
(1-78)
75.52
(2.39)
41.16
(1.16)
,54
(01)
10.42
(2.22)
Flavorless
45,08
(.87)
34.52
(.90)
29.01
(.40)
9.15
(.10)
2,48
(-04)
25,40
(.36)
86.10
(1.48)
75,26
(2.31)
42.35
(1-01)
.52
(.01)
12.00
(2.83)
Condition
Peppermint
46,89
(.50)
33,25
(.78)
29.05
(.43)
9.13
(-10)
2.71
(.16)
25.7!
(.29)
87.87
(1.57)
76,94
(2.14)
41.62
(1.00)
.54
(-01)
12.36
(3,02)
Cinnamon
45.99
(.63)
34.84
(-95)
28.98
(.41)
9.20
(.10)
2.65
(,!6)
25.91
(34)
89.61
(1.45)
76.26
(2.44)
41,96
(.99)
Cherry
45.37
(.81)
33.07
(-98)
29.94
(.45)
9.27
(.09)
2.72
(,17)
25.70
(.37)
88,94
(1,42)
75.19
(2,29)
41.57
(1.28)
.52
.53
(,01)
11.36
(2,49)
(-01)
11.87
(2.86)
Zoladz & Raudenbush
COGNITIVE ENHANCEMENT THROUGH
129
cinnamon gum condition, as compared to the no gum condition and the
chenry gum condition. There was a significant Gum x Task interaction
for design memory indicating that among the flavored gum conditions,
cinnamon- and peppermint-flavored gum produced the greatest delayed
memory percent correct scores, F^o.sso = 2.034, p<.0\. There was no
significant Gum x Sex interaction for scores on the design memory task,
F4.,,6 = 2.033. p>.05.
FIGURE 1. Mean Overall Three Letter Memory Scores for the Gum
Conditions in Phase I.
24
No Gum
Flavorless
Gum
Peppermint
Cinnamon
Cheny
Three Letter Task. A trend was found for gum condition, /^j.ue =
2,004, p = .099. Scores for the three letter task in the cinnamon gum
condition were greater than those scores in the no gum condition (see
Figure 1). There was also a significant Gum x Task interaction indicating
that the three letter total percent correct scores in the flavored gum
conditions were significantly greater tlian those scores in the flavorless
gum condition and the no gxim condition, FJO.SBC = 1.625, p<.05 (see
Figure 2), There was no significant Gtim x Sex interaction for scores on
the three letters task, /^4,|,6 = ,566,/)>.O5.
No other significant effects were found for the cognitive performance
scores in Phase I. Means and standard errors for all measures can be
found in Table 1.
Discussion
These results provide additional support that retronasal odorants can
enhance human behavior. While peppermint gum played a minor role in
130
NORTH AMERICAN JOURNAL OF PSYCHOLOGY
the results of design memory scores, cinnamon gum had the most
consistent directional influence on participants' cognitive performance.
Data trends indicated that design memory scores in the cinnamon gum
condition were greater than design memory scores in the no gum and
cherry gum conditions. Scores for the three letters task in the cinnamon
gum condition were also greater than those in the no gum condition,
These results suggest that a retronasal administration of a cinnamon
odorant has the potential to increase an individual's attentiona! processes,
virtual recognition memory, working memory, and visual-motor response
speed. Since the fmdings were not statistically significant, however, route
of administration may be playing a role in this effect.
FIGURE 2 Mean Three Letter Memory Total Percent Correct Scores for
the Gum Conditions in Phase I.
1
T
98,5
97.5
•
196.5
T
95,5
94.5
93.5
No Gum
Flavwless
Gum
Peppermint
Cinnamon
Cheny
The significant Gum x Task interaction for design memory suggested
that among the flavored gum conditions, cinnamon- and peppermintflavored gum produced the greatest delayed memory percent correct
scores. Thus, the cinnamon- and peppermint-flavored gums allowed for
participants to retain information in their memory for a longer period of
time. The significant Gum x Task interaction for the three letters task
suggested that the total percent correct scores in the flavored gum
conditions were significantly greater than those scores in the flavorless
gum and no gum conditions. This is of particular importance as it
suggests that flavored gum (in general) has the potential to enhance
working memory and visual motor response speed.
Zoladz & Raudenbush
COGNITIVE ENHANCEMENT THROUGH
131
Thus, the effects of retronasal odorants on human behavior are taskdependent; i.e., retronasal odorants enhance performance on particular
cognitive tasks. Evidence that particular flavors of gum can enhance
working memory links directly to research performed by Wilkinson, et
al. (2002), where flavored gum (Wrigley's Extra* Spearmint) facilitated
episodic memory and working memory. The present study finds the same
effects, but for different flavors of gum.
PHASE n: ORTHONASAL
Previous research has shown that an orthonasal peppermint fragrance
can significantly enhance athletic performance (Raudenbush, et al.,
2002b; Raudenbush, et al., 2001), decrease perceived workload for a
given task (Raudenbush, et al.. 2002a, Raudenbush, et al., 2002b), induce
physiological arousal (Raudenbush, et al., 2002a), and enhance one's
mood (Knasko, 1992). In Phase II, it was hypothesized that the
adrtunistration of a peppermint fragrance would significantly enhance
participants' cognitive performance. Given the findings of Phase I, it was
also hypothesized that the administration of a cinnamon fragrance would
significantly enhance participants' cognitive performance, particularly on
the design memory and three letter tasks, which were enhanced by the
administration of this odorant in Phase I. It was expected that these
effects would be more pronounced m Phase II, given an orthonasal route
of administration.
Method
Participants. Participants were 39 young adult volunteers (3 males, 36
females, mean age = 18.38 years) obtained through convenience
sanpling, and were different from those participants in Phase I.
Participants were students in a variety of psychology classes and received
course credit for participation. Three participants were removed from
primary data analyses to limit age variance [ages >30, (A/ = 45.33, SD =
10.79)].
Stimuli. In each odorant condition, peppermint, cinnamon, or jasmine
odor (Atdrich Co.) was added to low flow (1.3 Umin) oxygen via an
Airsep Newlife oxygen concentrator, and delivered to the participants
through a nasal cannula bi-rhinally. In the control condition, only low
flow oxygen was administered. The jasmine condition was included as a
further con^arison, since its effects are quite the opposite of peppermint
and cinnamon, i.e. relaxing rather than stimulating (Raudenbush, Koon,
Smith, & Zoladz, 2003). No cherry odorant condition was used due to
the findings of Phase I, where cherry gum had no significant in5)act on
cognitive performance.
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NORTH AMERICAN JOURNAL OF PSYCHOLOGY
Cognitive Performance Software. The Intact® sofhvare was
en^loyed, as per Phase I.
Additional Inventories. Profile of Mood States (POMS; McNair, Lon,
& Droppleman, 1971), The POMS contains 65 mood adjectives to which
participants indicate the extent to which each describes them. Sub-scales
related to fatigue, anxiety, and alertness are calculated.
NASA-Task Load Index (NASA-TLX; Hart & Staveland, 1988). The
NASA-TLX measures workload along three dimensions (mental,
physical, and ten^oral demand) related to demands imposed on the
participant by the task, and three dimensions (effort, frustration, and
performance) related to the interaction of the participant and the task.
Procedure
Participants were briefed as to the nature of the study (although not
about which odors would be used), produced written consent, provided
demographic information, and completed a pre-test POMS questionnaire.
TABLE 2 Means and Standard Errors for the Cognitive Performance
Scores in Phase II
Task
Word
Discrimination
Design Memory
X's and O's
Symbol Matching
Color Match
Three Letters
Verbal Memory
Composite
Visual Memory
Composite
Visual Motor
Speed Comp.
Reaction Time
Composite
Impulse Control
Composite
No Odor
44.61
(.79)
38.93
(1,08)
28.69
(.21)
9.18
(.08)
2.47
(.04)
25,55
(.25)
88.31
(1.30)
73.10
(2.13)
41.11
(1.16)
.54
(.01)
9,08
(1.44)
Condition
Peppermint
Jasmine
44.25
44,39
(.60)
(.61)
40.19
39.15
(1.08)
(1.03)
28,61
28.73
(.24)
(.20)
9.25
9.16
(.09)
(.07)
2.51
2.50
(.03)
(.03)
25.59
25,13
(.25)
(.36)
87.00
87.82
(1.44)
(1,26)
73.95
76.87
(2.27)
(1-89)
42,63
41.57
(1,00)
(1.09)
.54
.53
(.01)
(•01)
9.59
9,08
(1,65)
(1.22)
Cinnamon
44.93
(.59)
40,68
(1.04)
28.74
(.27)
9.25
(.09)
2.48
(.04)
25,87
(.26)
89.44
(1.27)
75.90
(2.04)
41.52
(1.22)
.53
(01)
9.90
(1.59)
Zotadz & Raudenbush
COGNITIVE ENHANCEMENT THROUGH
133
After connection to the odorant delivery system, participants
completed the Impact* test. Finally, participants completed a post-test
POMS questionnaire and completed the NASA-TLX workload
assessment.
The protocol was performed four times in a rejwated measures design
with each participant experiencing all conditions, and with each session
being separated by at least 24 hours. The order of the conditions was
randomly assigned, and each session lasted approximately 4S minutes.
Results
Cognitive Performance Scores.' Two-within (cognitive task, odor
condition) ANOVAs were performed to compare scores for the various
cognitive tasks among the odorant conditions. One-within (odor
condition) ANOVAs were performed to compare composite scores
among the odorant conditions. Alpha was set at .05 for all analyses, and
Tukey HSD Post-hoc contrasts were perfonned to determine lhe direction
of effects.
FIGURE 3 Mean Design Memory Delayed Memor>' Percent Correct
Scores and Design Memory Total Percent Correct scores for
the Odorant Conditions in Phase II.
No Odor
Peppermint
Jasmine
Cinnamon
• Delayed Memory Percent Correct • Total Percent Correct
Design Memory Task. There was no significant effect for odor
condition, fj.n* = 1,696. p>.05. However, there was a significant Odor x
Task interaction, suggesting that delayed memory percent conect scores
and total percent correct scores were greatest in the cinnamon odorant
condition, F\t,6u "= I.710,;?<.05 (see Figure 3).
134
NORTH AMERICAN JOURNAL OF PSYCHOLOGY
Three Letter Task. There was no significant effect for odor condition,
^j.tn - 1.910,;? = .132. There was a significant Odor x Task interaction,
suggesting that the percent of total letters conect scores were greatest in
the cinnamon condition. Fis.s7o = 2.461, /K.Ol. No other significant
effects were found for scores of cognitive performance in Phase II.
Means and standard errors for all measures can be found in Table 2.
Workload Measures. One-within (odor condition) ANOVAs were
performed to assess workload differences among the odorant conditions.
No significant effects were found for any of these measures.
Mood Measures. Measures of mood were calculated before and after
each condition by use of the POMS questionnaire. For each condition,
the difference was taken between the pre- and post-recordings as an
indication of the change in these variables during the experimental
session. One-within (odor condition) ANOVAs were performed to
compare these changes.
Vigor. A significant effect was found for odor condition, Fj.m =
3.058, /f<.05. Levels of vigor in the peppermint condition showed a
significantly smaller prc-post decline than the levels of vigor in the no
odor and cinnamon conditions.
Fatigue. A significant effect was found for odor condition, Fj^w =
2.922, p<.05. Levels of fatigue in the peppermint and jasmine conditions
showed a significantly greater pre-post decline than the levels of fatigue
in the cirmamon condition.
No other significant effects were found for die measures of mood in
Phase II.
Discussion
The results of Phase II support those of Phase I, suggesting that
cinnamon, administered retronasally and orthonasally, exhibits promise
in enhancing cognition. Once again, however, the relationship between
odorant administration and cognitive enhancement is task-dependent.
The significant interaction for design memory suggests that delayed
memory percent correct scores and total percent correct scores were
greatest in the cinnamon odorant condition; this is consistent with the
results of Phase I, where the cinnamon-flavored gum significantly
enhanced design memory delayed memory percent correct scores.
Additionally, the significant interaction for the three letters task indicated
that the percent of total letter correct scores were greatest in the
cinnamon odorant condition. Results of Phase I indicated that the three
letter total percent correct scores were greater in the fiavored gum
conditions than in the no gum and flavorless gum conditions. The Phase
n finding extended this interaction in Phase I, suggesting that the
cinnamon odorant has a more pronounced effect (than other odorants) for
Zoladz & Raudenbush
COGNITIVE ENHANCEMENT THROUGH
135
this task when administered orthonasally—route of administration does
play a role in the amount of influence an odorant has on the enhancement
of cognitive processing related to this task. This finding is con^arable to
that of Puttanniah, et al. (2001) who found that odorants have a greater
effect on human behavior if they are administered orthonasally.
Regarding the task-dependent relationship between odorants and
cognitive enhancement, the fmdings in Phase II suggest that cinnamon
odorant has the greatest potential to enhance attentional processes, virtual
recognition and working memory, and visual-motor response speed. Of
primary importance is the fact that cinnamon had a more pronounced
influence on cognitive processing for the same scores on the same tasks
in Phase II as it did in Phase I.
The significant odorant effects for pre-post changes in levels of vigor
and fatigue support the notion that peppermint is an invigorating odorant
that prevents fatigue from affecting individuals during a task. However,
since the peppermint odorant had no significant effect on the cognitive
performance of individuals, these results provide no evidence for an
interaction between peppermint, mood, and cognition.
FIGURE 4 Mean Overall Three Letter Memory Scores for the Odorant
Conditions in Phase II: Data from Participants Excluded
&om Original Data Analyses Due to Age.
16
No Odor
Peppermint
Jasmine
Cinnamon
Summary
Past research has consistently found that the administration of a
stimulating peppermint fragrance increases pain tolerance (Raudenbush,
et al, 2002a), reduces workload (Raudenbush, et al., 2002a; Raudenbush,
136
NORTH AMERICAN JOURNAL OF PSYCHOLOGY
et al., 2002b), enhances athletic performance (Raudenbush, et al., 2002b;
Raudenbush, et al., 2001), and induces physiological arousal
(Raudenbush, et al., 2002a). The present study suggests that another
stimulating odorant—cinnamon—can enhance human cognitive
performance. The fragrance, administered retronasally and orthonasally,
can enhance one's attentional processes, virtual recognition memory,
working memory, and visual-motor response speed.
The current findings have provide a foundation for ways to improve
cognition, and additional groups of individuals should be studied, such as
those who are declining cognitively with age, suffering test anxiety, or
suffering from diseases that lead to dementia. Though the present study
considers non-clinical participants, its findings call for an assessment of
cinnamon's effects on the cognition of individuals with such afflictions.
Footnote
'in order to examine the effects of age on an odorant's ability to
enhance cognition, participants originally excluded from the data
analyses were included in two-within (cognitive task, odor condition)
ANOVAs to compare their scores on the three letter task. One ANOVA
compared scores of all forty-two participants (i.e. older participants plus
younger participants), while the other ANOVA solely compared scores
ofthe older participants. Three Letters - Older + Younger: There was a
significant effect for odor condition, F3_i23 = 3.700, g<.05. Scores on the
three letter task in the cinnamon and peppermint conditions were
significantly greater than scores on the three letter task in the jasmine
condition. Further, there was a significant Odor x Task interaction
suggesting that the total sequence correct scores, total letters correct
scores, and percent of total letters correct scores were greatest in the
cinnamon condition, Fjs,6[5 = 3.826, p<.00\. Three Letters - Older: A
trend was found for odor condition, fj.e = 3.726, p = .08. Post-hoc
contrasts revealed that scores on the three letter task in the cinnamon
condition were greater than scores on the three letter task in the jasmine
condition (see Figure 4). Additionally, there was a significant Odor x
Task interaction suggesting that the total sequence correct scores, total
letters correct scores, and percent of total letters correct scores were
greatest in the cinnamon condition, f;j.3o = 6.226, p<.001. Thus,
cinnamon, administered orthonasally, may be particularly salient in the
enhancement of cognition in elderly individuals. Such a significant
fmding provides a solid foundation for finding ways to improve memory
and other cognitive functions in individuals experiencing age-related
dementia. It also calls for research directed at enhancing these
individuals' cognition via orthonasal odorant administration.
Zoladz & Raudenbush
COGNITIVE ENHANCEMENT THROUGH
137
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APPENDIX A
Iir^act Software Program Assessments
Assessment #1 - Word Discrimination
This test assesses artentional processes and verbal recognition
memory. Twelve words are presented on the computer screen,
each for approximately 750 milliseconds. Subsequently,
participants are presented with 24 different words, 12 of which
were part ofthe list they just viewed, and 12 of which were not
part ofthe list they just viewed. Participants must decide which
words were part of the list and which words were not part of the
list by supplying a "yes" or "no" response to each ofthe 24
words presented.
Assessment #2 - Design Memory
This test assesses attentional processes and visual recognition
memory. Twelve various designs are presented on the computer
screen, each for approximately 750 milliseconds. After all
twelve designs have been presented, participants are presented
with 24 different designs, 12 of which were part ofthe list they
just viewed, and 12 of which were not part ofthe list they just
viewed. Participants must decide which designs were part ofthe
list and which designs were not part ofthe list by supplying a
"yes" or "no" response to each ofthe 24 designs presented.
Assessment #3 - X's and O's
This test assesses visual working memory and visual processing
speed. Individuals are presented with a random assortment of
X's and O's, 3 of which are highlighted in yellow. Participants
are required to remember the location of the 3 highlighted letters
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and recall that information after performing a distractor task (i.e.
a task that is presented between the primary exposure to the
information and the cued recall of that information in an atten^t
to challenge the working memory of participants). After
viewing the highlighted letters for approximately 1.5 seconds
and also performing the distractor task, participants are asked to
recall the location ofthe 3 highlighted letters. Participants
repeat this task for a total of 4 trials.
Assessment #4 - Symbol Matching
This test assesses visual processing speed, learning, and
memory. At the top of the computer screen, participants are
presented with a grid that matches 9 numbers to 9 common
symbols (i.e. star, triangle, square, arrow, etc.). At the bottom
of the screen, participants are presented with a random symbol
to which he or she must tnatch with a number on the top ofthe
screen. After 27 practice trials have been completed, the
symbols paired with the numbers on the top of the screen
disappear. Subsequently, participants are again presented with
random symbols at the bottom ofthe screen, and he or she mtist
recall to which number the specific symbol was paired. This
assessment records a reaction time score and a memory score.
Assessment #5 - Color Match
This test assesses reaction time and impulse control/response
inhibition. Before begitining the assessment, participants are
asked to click a "RED," "BLUE," and "GREEN" button as it is
presented on the screen. This screening procedure helps assure
that subsequent trials will not be affected by color blindness.
Thereafter, words are presented in either the same color of ink
as the words read ("blue" in blue ink) or a different color of ink
("blue" in red ink). Participants are asked to click on the word
only if the word is printed in the same color of ink as the word
reads.
Assessment #6 - Three Letters
This test assesses working memory and visual-motor response
speed. Before testing, participants are allotted time to practice a
distractor task, consisting of 25 grid blocks ( 5 x 5 grid design)
numbered 1-25 in random order. Participants must click on the
blocks in reverse order, starting with block #25 and progressing
through block #1, Once the test begins, participants are
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presented with three consonant letters (e.g. WFL). Immediately
after these letters have been displayed, they are removed and the
participant must complete the distractor task. He or she is once
again asked to perform the numbered grid task described above
as quickly as possible. Once 18 seconds have elapsed, the gnd
disappears, and the participant is asked to recall the three letters
that were displayed on the screen earher.