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been widely accepted. Despite the persistence of AD/HD
symptoms into adulthood, there have been few studies of the
cognitive effects of green space on older individuals. From the
perspective of attention restoration theory, differing environ-
ments have varying impact on attentional resources. Settings
requiring a higher level of focus and directed attention result in
decrements in attentional functioning over time. Green space is
believed to be “gently absorbing” and restores involuntary at-
tention through its ability to “rest and rejuvenate” (Taylor &
Kuo, 2009; p. 403) cognitive functioning. In addition, since
green vegetation is climate- and season-dependent in many
regions, it would be of interest to examine the cognitive impact
of outdoor exposure in winter in a geographic region with four
distinct seasons. To date, there has been no research examining
whether this effect applies to colder climates or seasons (win-
ter/early spring).
While there is some support for the green space-attention
restoration hypothesis, the mechanism involved is not clear. Of
note, Faber Taylor and Kuo (2009) found that participants re-
ported a more positive affective experience in the park com-
pared with the other two settings. It is possible that the cogni-
tive benefits may accrue from exercise and its impact on neural
activity or through the psychological benefits of exercise in
fostering a sense of well-being.
The current study is an attempt to partially replicate and ex-
tend Taylor and Kuo’s (2009) finding that a 20 min. walk in a
park-like setting (green space) was associated with greater lev-
els of improved attention and concentration compared with a
walk of the same duration in a downtown or neighborhood
setting.
In the current study, adults will participate in an outdoor ac-
tivity (a walk) in three different locations: a wooded trail, a
parking lot, and a mixed residential business neighborhood for
a 20 min. interval. Participants will be randomly assigned to
only one of these conditions and their attention, concentration,
and short-term memory as well as their emotional state will be
assessed immediately before and after the activity. As an addi-
tional measure, the Wechsler Memory Scale was administered.
It has been noted that this test requires more active processing
of information than the digit span task and more closely ap-
proximates the type of deficits that adults with attentional
problems report in their daily lives (Quilan & Brown, 2003).
Specifically, it was hypothesized that adults walking in a
wooded, partially snow-covered setting would demonstrate
greater improvement on the Digit Span and Logical Memory
tasks relative to those walking in a paved parking lot or resi-
dential/business neighborhood. In addition, since it has been
established that aerobic activity has some emotionally benefi-
cial effects, we administered the Profile of Mood States (POMS)
to all three groups immediately before and after the walk
Methods
Participants
Potential participants were recruited primarily from upper-
level undergraduate psychology classes. However, the majority
of participants were not psychology majors. A total of 26 par-
ticipants, seven male and 19 female university students with an
approximate age range of 19 to 24 years, were randomly as-
signed to one of the three outdoor conditions: Woods-9; Neigh-
borhood-8; Parking Lot-9. Because of scheduling issues, the
participants completed the walk in groups of two to four indi-
viduals. Participants were instructed not to converse with one
another during the guided walk led by the first investigator.
Measures
Wechsler Memory Scale—Revised: Immediately before and
after the walk, all participants were administered the following:
three tasks from the Wechsler Memory Scale-Revised (Wechs-
ler, 1987) digit span forwards (DSF), digit span backwards
(DSB), and logical memory (LM). The digit span tests are sen-
sitive to attention and concentration and are frequently used in
diagnostic evaluations for AD/HD (Hale, Hoeppner, & Fiorello,
2002). The digit span tasks require the participant to repeat a
progressively longer string of numbers immediately after verbal
presentation by the examiner with directions to say the numbers
in reverse order for the digits backwards task. The number se-
quences were taken from the Wechsler Memory Scale-Revised
Manual (Wechsler, 1987) for the pretests of the digits forward
and backwards. The post-test sequences were generated with a
random number table but followed the same presentation for-
mat. The Logical Memory (LM) task is used to assess short-
term memory. The LM task consists of listening to a short story
immediately followed by the instruction to verbally recall the
story. A total score is computed based upon the total segments
correctly recalled. Two comparable, yet different, stories were
administered as pre- and post-tests, respectively. Inter-scorer
reliabilities .90 and above have been reported for immediate
recall of both forms (Lezak, 1995).
The Profile of Mood States: The Profile of Mood States
(POMS; McNair, Lorr, & Droppleman, 2005) is one of the
most commonly employed affective state measures in exercise
and sports psychology. The POMS was developed to assess
affective states and short-term changes in emotion. Items are
rated on a five point scale and grouped into six dimensions:
Tension-Anxiety (T), Depression-Dejection (D), Anger-Hostil-
ity (A), Vigor-Activity (V), Fatigue-Inertia (F), and Confusion-
Bewilderment (C). The POMs is administered with participants
being asked to rate their emotional state with respect to a spe-
cific time frame typically ranging from the past week to imme-
diate present (McNair, Lorr, & Droppleman, 2005). Internal
consistency reliabilities range from .65 to .74 (Hansen, Stevens,
& Coast, 2001). Factor analytic studies have yielded six dimen-
sions with content generally consistent with the subscale names
noted above (Nyenhuis, Yamamoto, Luchetta, Terrien & Par-
mentier, 1991).
Procedure
Participants were randomly assigned to one of the three
treatment groups by way of a random number table. Based on
availability, participants completed the protocol on a weekday
beginning as early as 1:00 p.m. and ending as late as 7:00 p.m.
Participants were tested individually. Prior to the walk, the
participants completed the POMS, background information
questionnaire, and the consent document. In addition, the first
author administered the digit span forwards, digit span back-
wards and logical memory tests. Immediately after testing, the
participants were taken on a guided 20-minute walk in groups
of two to four persons, at a moderate pace and generally level
terrain, for each treatment group. Participants were instructed
not to converse with one another during the guided walk led by
the first investigator. The completion of the post-walk POMS
and cognitive tasks followed the same order as the pre-testing.
Results
Review of the data set resulted in the removal of one Neigh-