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					                                                                                                                             Matthew                                         Winchester1
Abstract                                                                                                                           2, Ph.D. Sponsor: Newmont Mining
                                                                                                                                                                                                                       Frontier of Science 20111, Dept. of Psychology2, UNC

Executive function (EF) is a broad term for the higher order thought processes that are used in
new situations, things like problem-solving, working memory, inhibitory control, and planning. It
                                                                                                             Mentor: Marilyn Welsh
can be separated into two divisions, “hot” EF dealing with emotionally and motivationally                        Iowa Gambling Task
influenced decisions, and “cold” EF dealing with purely cognitive problem solving. This study                    • Measure the risky decision making of the participants in a computerized, hypothetical gambling
examined the various similarities and differences between “hot” and “cold” executive function,                      situation.
                                                                                                                                                                                                                                                                        Fig. 3                                    Fig. 4                                     Fig. 5
and attempted to make “cold” tasks “hotter” through giving traditional “cold” EF tasks in an                     • “Hot” EF task.
incentive condition. A total of 10 volunteer participants from the 2011 FSI program, ranging in                  • Requires the participant to makes a series of selections from an electronically delivered
age from 15 to 17, were tested through the use of the Iowa Gambling Task (IGT), Tower of                            (computerized) display of four card decks, A, B, C, or D.
London (TOL), and Letter-Number Sequencing (LNS). The IGT represented a typical “hot” task,                      • When a card is chosen by a mouse click, it results in a hypothetical win or a loss of some money
while both TOL and LNS were “cold” tasks. Performance on the TOL and LNS under non-incentive                        and the task taker’s running total of the amount of money won and the amount of money
conditions did not correlate, and neither did the TOL or LNS under non-incentive conditions.                        borrowed is displayed on the top of the computer screen.
However, the TOL task under incentive conditions did strongly correlate with scores on the IGT,
indicating that the “cold” task became “hotter”. Future studies in this area should include a larger
                                                                                                                 • 100 trials given in 5 blocks of 20.
                                                                                                                 • Two “good” decks (C and D) and two “bad” decks (A and B).
                                                                                                                                                                                                                                         Discussion
                                                                                                                                                                                                                                         The primary purpose of this experiment was to study the effects of incentive and non-incentive
sample size in order to gather more definitive data and gain stronger statistical power.                         • “Bad” deck has a high reward but occasionally results in a very large loss. The “good” deck has
                                                                                                                                                                                                                                         conditions on traditionally “cold” executive function tasks (Tower of London, Letter-Number
                                                                                                                    minimal reward but occasionally results in only a small penalty.
                                                                                                                                                                                                                                         Sequence), and to see that, while given during incentive conditions, the tasks would correlate more
                                                                                                                 • The participant is unable to predict when they will lose or win money; however, they
                                                                                           Figure 1. The                                                                                                                                 closely to a “hot” EF task (Iowa Gambling Task). The TOL and LNS would effectively become
                                                                                                                    presumably can figure out over time which are good decks and which are bad decks.
                                                                                                                                                                                                                                         “hotter” under the incentive conditions.
                                                                                           prefrontal            Tower of London (fig. 2)
                                                                                                                                                                                                                                         The research question addressed how the incentive manipulation would influence the
                                                                                                                 • “Cold” EF task.
                                                                                           cortex is             • The point of the task is to move the balls, one at a time, to build the goal pattern that is
                                                                                                                                                                                                                                         performance (number correct) on the TOL and LNS tasks. The paired-samples t-test performed on
                                                                                           thought to be                                                                                                                                 the data collected showed almost no differences in performance on the TOL or the LNS tasks under
                                                                                                                    presented to the student on a large card. The balls are set up in a “starting pattern” and the
                                                                                                                                                                                                                                         incentive and non-incentive conditions.
                                                                                           the location of          participant is told how many moves (4, 5, or 6) it will take to move the balls into the goal
                                                                                                                                                                                                                                         Hypothesis 1 stated that the scores on the TOL and LNS tasks given under non-incentive conditions
                                                                                                                    pattern.
                                                                                           executive             • The 15 odd problems were given under incentive conditions, and the 15 even under standard
                                                                                                                                                                                                                                         would be moderately correlated with each other because they are both considered to be “cold” EF
                                                                                           function                                                                                                                                      tasks. Based on the results of the experiment, the hypothesis was not supported by the data.
                                                                                                                    conditions.
                                                                                                                                                                                                                                         Correlational analysis revealed a non-significant correlation.
                                                                                                                 Letter-Number Sequencing
                                                                                                                                                                                                                                         Hypothesis 2 said that the scores on the TOL and LNS tasks given under non-incentive conditions
                                                                                                                 • “Cold” EF task, specifically working memory
Introduction                                                                                                     • The participant is read a combination of numbers and letters and is asked to recall the numbers
                                                                                                                    first in ascending order and then the letters in alphabetical order.
                                                                                                                                                                                                                                         will be correlated with the “hot” EF task, IGT, at a low magnitude. This hypothesis was also
                                                                                                                                                                                                                                         unsupported by the data, with only an insignificant correlation for both the TOL and LNS. However,
Executive function (EF) consists of the higher order thought processes that are essential in novel                                                                                                                                       an interesting trend was seen between the TOL and Block 1 of the IGT, where a strong negative
                                                                                                                 • There are seven items ranging from 2-letter/number sequences (e.g., B-7) to 8-letter/number
situations, such as problem-solving, working memory, inhibitory control, planning, etc. (Gilbert &                                                                                                                                       correlation was seen. This finding suggests that participants who performed better on the TOL
                                                                                                                    sequences (e.g., S-2-L-8-B-1-G-7).
Burgess, 2008), which are thought to occur in the frontal lobe region of the brain (fig. 1) (Gilbert &                                                                                                                                   under non-incentive conditions did worse (made more risky choices) on the beginning 20 trials of
                                                                                                                 • 7 trials were given under each condition
Burgess, 2008). The prefrontal cortex consists of the front most part of the frontal lobes, and is                                                                                                                                       the IGT.
thought to be the part of the brain that is responsible for executive function. The prefrontal cortex                                                                                                                                    Similar to Hypothesis 2, Hypothesis 3 stated that the scores on the TOL and LNS tasks, but given
can be divided into several sections: the dorsolateral (responsible for “cold” EF), the orbitofrontal                                                                                                                                    under incentive conditions, will be correlated with the “hot” EF task, IGT, at a moderate to high
(responsible for “hot” EF), and the frontopolar (theorized to be the site of cognitive branching)                                                                                                                                        magnitude. Correlational analysis on the LNS under incentive conditions against the individual IGT
(Hongwanishkul et al., 2010). Executive function can be further divided into two groups, both                                                                                                           Figure 2. A                      trials and total net score showed a very small, non-significant correlation that ranged from being
“hot” and “cold” executive function, to describe the emotional and cognitive aspects associated                                                                                                                                          positive to negative. However, the TOL under incentive conditions showed a significant correlation
with each respectively (Prencipe et al., 2011).
                                                                                                                                                                                                        typical Tower                    to Blocks 2-5 and the net total of the IGT. These are the most important findings of this study, and
The “hot” EF deals with emotionally and motivationally influenced decisions, and “cold” EF                                                                                                              of London                        although much more research does need to be performed, it does indicate that under incentive
concerns cognitive problem solving. “Hot” executive function involves traditional EF when there is                                                                                                      problem                          conditions, the TOL (a “cold” task), did become “hotter” by correlating more closely with the IGT (a
a strong motivation to perform well, especially emotional or motivational influence                                                                                                                                                      “hot” task).
(Hongwanishkul et al., 2010). “Cold” (or “cool”) executive function involves the purely cognitive                                                                                                                                        Future studies involving “hot” and “cold” executive function can improve on many of the flaws
aspect of EF, where there is little or no emotional or consequential influence.                                                                                                                                                          seen in this experiment. Most importantly, a much larger sample must be tested, in order to
The purpose of this study was to observe executive functions (EF) under incentive and non-                                                                                                                                               collect more data, and eliminate many of the problems seen with testing a small sample, such as
incentive conditions, using a traditionally “hot” task (Iowa Gambling Task) and “cold” tasks (Tower                                                                                                                                      outliers strongly effecting the correlations, etc.
of London, Letter-Number Sequencing). Through the use of incentive and non-incentive settings, it
is predicted that these “cold” tasks will become “hotter”. The data collected from our study will be
                                                                                                                 Results                                                                                                                 Although this study shows little practical implications, mainly due to the small sample size, it does
                                                                                                                                                                                                                                         show the need for further research in this area of study. “Hot” and “cold” executive function is still
used to answer these three hypotheses, as well as our research question:                                         The descriptive statistics (means and standard deviations) for the experimental measures can be                         being studied, and larger experiments are critical to understanding the many similarities and
Research Question (no apriori hypothesis): How will the incentive manipulation influence the                     found on Table 1 below.                                                                                                 differences between them. Finding a strong correlation between the TOL under incentive
performance (number correct) on the TOL and LNS tasks?                                                           The research question addressed how the incentive manipulation would influence the                                      conditions and IGT (while there was none between the TOL under non-incentive conditions and
Hypothesis 1: The scores on the TOL and LNS tasks given under non-incentive conditions will be                   performance (number correct) on the TOL and LNS tasks. The paired-samples t-test showed no                              the IGT) is a very interesting result, and further experimentation could support or hurt this finding.
moderately correlated with each other because they are both considered to be “cold” EF tasks.                    significant differences in performance on the TOL or the LNS tasks under incentive and non-
Hypothesis 2: The scores on the TOL and LNS tasks given under non-incentive conditions will be                   incentive conditions.
correlated with the “hot” EF task, IGT, at a low magnitude.
Hypothesis 3: The scores on the TOL and LNS tasks given under incentive conditions will be
                                                                                                                 Hypothesis 1 stated that the scores on the TOL and LNS tasks given under non-incentive conditions
                                                                                                                 would be moderately correlated with each other because they are both considered to be “cold” EF                         Acknowledgements
                                                                                                                 tasks. Correlational analysis found a non-significant positive correlation, r (8) = 0.268, p = 0.227                    I’d like to thank Dr. Welsh for all her tremendous help on this project and paper, including the design of the study in the first place.
correlated with the “hot” EF task, IGT, at a moderate to high magnitude.                                                                                                                                                                 She was an excellent mentor, and always answered any questions I had during the research process. I would also like to thank
                                                                                                                 (fig. 3). The scatter-plot indicates a positive association, however many outliers caused the                           Nathan Kirkley and Zabedah Saad for their help on editing this paper. My best regards go out to Lori Ball and UNC, for maintaining a
                                                                                                                 correlation to be non-significant.                                                                                      science program as awesome as FSI. Lastly, I’d like to thank Newmont Mining for sponsoring me to attend this program; it has been
Methods/Measures                                                                                                 Hypothesis 2 stated that the scores on the TOL and LNS tasks given under non-incentive conditions
                                                                                                                 will be correlated with the “hot” EF task, IGT, at a low magnitude. Correlational analysis once again
                                                                                                                                                                                                                                         a truly life-changing experience.

Participants
A total of 10 teenagers ranging from ages 15-17 (mean = 16.1, std. deviation = 0.57) voluntarily
participated in this study. The group contained 5 boys and 5 girls. All participants are active
                                                                                                                 found a non-significant positive correlation between the non-incentive TOL and IGT. This suggests
                                                                                                                 that better scores on the TOL were related to better (less risky) choices on the IGT. The exception                     References
                                                                                                                 to this finding was the first block of 20 IGT trials in which there was a significant negative                          Baddeley, A. (2010, February 23). Working memory. Current Biology, 20(4).
members of the 2011 Frontiers of Science Institute.                                                                                                                                                                                                                                    D
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General Procedure
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                                                                                                                 conditions and IGT, meaning that higher scores on the LNS resulted in poorer choices on the IGT.                                                                    A
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                                                                                                                 negative correlation, r (8) = -0.536, p = 0.055.
participants were informed that their performance on the tasks would determine the number of                                                                                                                                             Gilbert, S. J., & Burgess, P. W. (2008, February 12). Executive function. Current Biology, 18(3).
                                                                                                                 Hypothesis 3 stated that the scores on the TOL and LNS tasks given under incentive conditions will                      Hongwanishkul, D., Happaney, K. R., Lee, W. S. C., & Zelazo, P. D. (2010, June 8). Assessment of Hot and Cool Executive Function in
entries to receive a prize. After the Iowa Gambling Task (IGT) the group was given another 15
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Tower of London problems and 7 more Letter-Number Sequencing problems, where they were told                                                                                                                                              Kerr, A., & Zelazo, P. D. (2004, June). Development of “hot” executive function: The children’s gambling task. Brain and Cognition,
                                                                                                                 yielded several significant positive correlations between the TOL under incentive conditions and
that the performance would not count toward entries for the prize. For the second group of                                                                                                                                               55(1).
                                                                                                                 IGT Block 2, r (8) = 0.598, p = 0.034, IGT Block 3, r (8) = 0.726, p = 0.009, IGT Block 4, r (8) = 0.725, p             Prencipe, A., Kesek, A., Cohen, J., Lamm, C., Lewis, M. D., & Zelazo, P. D. (2011). Development of hot and cool executive function
participants, 15 Tower of London problems and 7 Letter-Number Sequencing problems were given
                                                                                                                 = 0.009, IGT Block 5, r (8) = 0.633, p = 0.025, and the IGT net total, r (8) = 0.776, p = 0.004 (fig. 5).               during the transition to adolescence. Journal of Experimental Child Psychology, (108).
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                                                                                                                 Correlations between the LNS under incentive conditions and the IGT were all non-significant,
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                                                                                                                 ranging from negative to positive.                                                                                      adolescence: Implications for developmental psychopathology. Cognitive Development, (22).
participants being told that performance on these tasks would count towards the drawing.

				
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