The Huron University College Journal of Learning and Motivation Volume 52 Issue 1 Article 6 2014 Cue Saliency and Age as Factors Affecting Performance in a Card Sorting Task Rebecca Herbert Huron University College Follow this and additional works at: http://ir.lib.uwo.ca/hucjlm Part of the Psychology Commons Recommended Citation Herbert, Rebecca (2014) "Cue Saliency and Age as Factors Affecting Performance in a Card Sorting Task," The Huron University College Journal of Learning and Motivation: Vol. 52: Iss. 1, Article 6. Available at: http://ir.lib.uwo.ca/hucjlm/vol52/iss1/6 This Article is brought to you for free and open access by the Psychology at Scholarship@Western. It has been accepted for inclusion in The Huron University College Journal of Learning and Motivation by an authorized administrator of Scholarship@Western. For more information, please contact jpater22@uwo.ca.
Factors Affecting a Card Sorting Task 82 Cue Saliency and Age as Factors Affecting Performance in a Card Sorting Task Rebecca Herbert Huron University College at Western Abstract The present study aimed to identify if cue saliency could be manipulated in a card-sorting task in a way that would hinder task performance. Specifically, it was predicted that when four similar colours were used in a card-sorting task similar to the Wisconsin Card Sorting Task, performance would suffer. It was also predicted that there would be a significant difference in performance between individuals in their early twenties and individuals in their forties and fifties. The results suggested no significant difference in performance between the control and experimental group, F (1,24) =.21, p>.05, partial 2 =.009, as well as no significant difference in performance between age groups, F (1,24) =.48, p>.05, partial 2 =.019. Keywords: human cognition, card-sorting, cue saliency The Wisconsin Card Sorting Task (WCST) was a task developed to measure a person s ability to adapt or shift their way of thinking based on feedback (Berg, 1948). The task involves having a person sort a set of cards based on the image they contain. These images differ in three fundamental dimensions: shape, colour, and quantity. Specifically, cards may contain stars, crosses, triangles or circles, which may be red, yellow, blue or green, and there may be one, two, three, or four of the images on any given card. Cues that differentiate cards from one another are thought to be relatively equal in their salience; that is, people are not more inclined to sort cards by one particular rule over another. At the beginning of the task, four cards that differ in all 3 dimensions are placed in front of the participant. They are asked to sort the cards into groups by placing test cards one at a time on top of the pile that they believe it belongs to. The researcher gives the participant feedback after every card sorted, telling them whether they have sorted correctly. Correct categories, or sorting criteria are always predetermined. After correctly sorting five cards consecutively, the rule for sorting is changed to one of the two remaining
Factors Affecting a Card Sorting Task 83 dimensions, and the researcher adjusts his/her feedback accordingly. The task is considered complete after a participant successfully completes nine categories. Task performance is measured by calculating the average number of errors made by each participant. Berg (1948) found that the older individuals (ages 58-73) learned the first sorting rule but then showed an inability to shift to the new rule. It has since then been found that children and adolescents often struggle with shifting in the WCST, too (Bujoreanu & Willis, 2008). Because the prefrontal cortex (PFC) has often been associated with cognitive or executive control and an ability to orchestrate thought and action in accordance with internal goals, it is believed that the PFC plays an important role in allowing people to successfully complete the WCST (Miller & Cohen, 2001, p. 167). Evidence that the PFC is one of the last brain areas to mature as well as the first to deteriorate may give insight into why the WCST is much more difficult for both young children and older individuals (Miller & Cohen, 2001; Hampshire, Gruszka, Fallon & Owen, 2008). This theory has further been supported by research that has found that patients who suffer from lesions or damage to the PFC struggle to complete the WCST in much the same way (Milner, 1963). The Dimensional Change Card Sort Task (DCCST) was designed as a simpler version of the WCST, to be more suited for young children around 3 years of age (Fisher, 2010). Rather than cards differing in three dimensions, DCCST cards differ in only two dimensions: shape and colour. In the task, images may be one of two possible colours (Ex. red or blue), and one of two shapes (Ex. boats or flowers). Children are first asked to sort the cards based on one of the two dimensions, and generally are successful at this. However, after they have sorted all of the cards, they are asked to sort by the other dimension. Despite receiving reminders about the new rule,
Factors Affecting a Card Sorting Task 84 young children still tend to struggle to shift their sorting rule in the postswitch phase (Fisher 2010). A study conducted by Fisher (2010) aimed to determine whether it was possible to manipulate cue salience in a way that would make the task of shifting in the DCCST easier for children. It was hypothesized that through altering cue salience in the sorting task, specifically in the postswitch phase, children would have an easier time switching their sorting rule. For example, this was done through using similar colours (red and pink) and dissimilar shapes (stars and flowers) to render shape more salient. This prediction was based on the theory that the more similar two values are, the less salient is the contrast between these values (Fisher 2010, p. 214). It was predicted that if children were switching to a cue that was more salient, they would have an easier time learning and maintaining the new rule in the postswitch phase. Indeed, this hypothesis was confirmed: children who received the manipulated cards to sort performed 30% better than those who received the standard DCCST cards. The present study aims to determine whether cue salience may also be manipulated to make a task like the WCST more difficult for individuals. Specifically, because all cues (colour, shape and number) are relatively equally salient in the standard WCST, it is predicted that using four similar colours may make the task more difficult. Specifically, it is hypothesized that the rule of colour may be more easily overlooked when using cards such as these in comparison to the standard cards. In addition, the present study aims to identify any significant age difference in task performance between individuals in their early 20 s and individuals in their 40 s and 50 s. Based on research involving PFC function, it has been found that the task becomes easier with age to an extent, and then declines as that region begins to deteriorate. However, it is unclear at
Factors Affecting a Card Sorting Task 85 what specific age this peak occurs. It is predicted that there will be a significant difference between the two age groups, presumably due to differences in PFC function. Method Participants Participants in the study were 28 individuals recruited by the researcher. Participants were either under the age of 25 or over the age of 40. The younger participants consisted of friends and peers of the researcher, as well as some individuals recruited around the Huron College campus. The older individuals consisted of family of the researcher, as well as individuals who were recruited in the Masonville Mall food court in London, as well as workers at Leamington Chrysler. The mean age of the young participants was 21.14 years, and the mean age of the older participants was 51.86 years. There were a total of 14 males and 14 females in the study (4 males in the younger group, and 10 males in the older group). Materials The card-sorting task used in the present study was modeled after the WCST. The shapes used were squares, circles, crosses and triangles, and there were one, two, three, or four shapes on any given card. There were two sets of cards- set A and set B. In set A (the control group), images were red, green, blue, or yellow. In set B (the experimental group), however, cards were light pink, hot pink, red, or burgundy. See appendix A for a sample from each set. In each set there were a total of 18 cards, and each card was unique from the rest in that set. Procedure Individuals who agreed to participate in the study were seated across from the researcher. The researcher laid out four cards before the participant. In the control group, the cards were images of: one yellow square, two red crosses, three green triangles, and four blue circles. The
Factors Affecting a Card Sorting Task 86 cards were identical in the experimental group, except that yellow shapes were burgundy, green shapes were light pink, and blue shapes were hot pink (red shapes remained red). The participant was informed that they would be given a series of cards, one at a time, to sort into one of the four piles, based on whatever criteria they wished. They were also informed that the researcher would give them feedback whether they had sorted based on the correct rule or not, and that they should switch until they had selected the correct pile. A fundamental change from the standard WCST was made in the task used for the present study: rather than have sorting rules change systematically throughout the study, the sorting rules were set up in a random fashion to allow for less predictability for the participant. This was done so that participants would not learn a certain pattern of change throughout testing. Thus, the rule for sorting switched sporadically throughout the process. The researcher had predetermined correct sorting criteria ahead of time. A total of five switches occurred during each trial. The number of errors made by each participant was recorded as they sorted a total of 14 cards. When the participant sorted the last card correctly, they were thanked for their participation and given a debriefing form. Results The results of the study are shown in table 1. A 2X2 ANOVA was conducted with number of errors in the card-sorting task as the dependent variable and age (younger/older) and type of cards (control/experimental) as the independent variables. The results indicated that there was not a significant difference in task performance between younger individuals (M = 8.42, SD = 2.56) and older individuals (M = 9.71, SD = 6.23), thus showing no main effect for age, F (1,24) =.48, p>.05, partial 2 =.019. In addition, there was not a significant difference in task performance between control cards (M = 8.64, SD = 4.41) and experimental cards (M = 9.5, SD =
Factors Affecting a Card Sorting Task 87 5.14), thus showing no main effect for card type, F (1,24) =.21, p>.05, partial 2 =.009. Lastly, there was no age by card type interaction found, F (1,24) =.09, p>.05, partial 2 =.004. Table 1: ANOVA Table Dependent Variable df F Partial 2 p Age 1.476.019.497 Cards 1.212.009.650 Age * Cards 1.094.004.762 Error 24.094 Note: Significant at the p< 0.05 value. Discussion Previous research has shown that cue saliency may be manipulated during the DCCST to make the task easier for younger participants (Fisher 2010). The present study hypothesized that manipulation of cue saliency may impede task performance in a task similar to the WCST, specifically through using four very similar colours. In addition, it has been theorized that the PFC plays a crucial role in allowing for successful completion of the card sorting tasks, thus making performance difficult for both younger and older individuals (Miller & Cohen, 2001). The present study hypothesized that there would be a significant difference in task performance between individuals in their early 20 s and individuals in their 40 s and 50 s. Results of the present study did not support either of the hypotheses; there were no significant differences between any of the four groups. The scientific adequacy of the present study must be examined as a potential reason for the results. The sample size was rather small, and although an equal number of men and women partook in the study, they were not evenly dispersed between groups. Specifically, there were
Factors Affecting a Card Sorting Task 88 fewer young males sampled and more older males sampled. In addition, upon being invited to participate, some people said no and expressed concerns about failing miserably. Thus, it is possible that the only individuals who participated were ones who believed they could do well at such a task, leading to a more biased sample that was less reflective of the true population. In addition, it is possible that the age ranges used were too wide. Specifically, having the older group consist of individuals anywhere from 40-60 years of age may have been too large of a window to see an effect. This is especially true because of the research that shows the PFC is normally the first brain area to deteriorate; this may be too much of a time-sensitive matter to test with an age range of 20 years (Miller & Cohen, 2001). Sampling may have been improved by incorporating a larger, more diverse sample, with an equal number of males and females in each group, as well as a smaller age range for the older group. In addition to sampling, the card-sorting task used may have not been as reliable or valid of a measure as the actual WCST. Although it was modeled after the WCST, it is still unlikely that the card-sorting task used was just as effective of a measure. In addition, the researcher conducting the card-sorting task was not as qualified as testers that administer the WCST; the researcher may not have been unbiased throughout testing, and this may have had an effect on how well or poor people performed on the task. Furthermore, there were some outliers in the data collected- specifically, people who got notably more errors than their peers. The outliers were not eliminated from the data set. However, it is unclear why this occurred. It is possible that this was due to a poor understanding of the task itself, perhaps which was due to a poor explanation of the task by the researcher. Thus, the present study may have benefited from using a standardized card-sorting task such as the WCST, and having it administered by someone with professional training.
Factors Affecting a Card Sorting Task 89 An issue with any colourful card-sorting task is colourblindness- an issue that is most predominately found in males. If a colourblind male attempted the task, his performance may be severely hindered. This is especially true for the experimental group, where all colours used on the cards were around the red area of the colour spectrum. If a male did have a form of colourblindness that affected his perception of red, he would likely not be able to distinguish between any of the colours on the cards. This phenomenon may be a potential reason for some of the outlier data that was observed. It is difficult to get around the possibility of testing someone who is colourblind, unless males are eliminated completely from the study. However, doing this would also greatly affect the generalizability of the sample. A future study may first test males ability to distinguish between the four colours used in the task before actually beginning the task. This would ensure that results were more a measure of true task performance, rather than a measure of colour vision. Future research in the area may look at ways to help improve performance in card-sorting tasks for older individuals. Specifically, rather than trying to make the task more difficult for participants, future research may look at ways of manipulating cue saliency to make the task easier for older individuals, as Fisher (2010) did with children in the DCCST. Another possible area of research could be incorporating brain imaging techniques such as fmri into the card sorting tasks, in order to obtain more information about brain function in the card-sorting tasks, as well as to observe changes in brain function as age increases. Card sorting tasks give interesting insight into the function of the frontal lobe, specifically the PFC, and hold many possibilities for exciting research in the future.
Factors Affecting a Card Sorting Task 90 References Berg, E. A. (1948). A simple objective technique for measuring flexibility in thinking. Journal of General Psychology, 39, 15. Bujoreanu, I. S., & Willis, W. G. (2008). Developmental and neuropsychological perspectives on the wisconsin card sorting test in children. Developmental Neuropsychology, 33(5), 584-600. Fisher, A. V. (2010). Automatic shifts of attention in the dimensional change card sort task: Subtle changes in task materials lead to flexible switching. Journal of Experimental Child Psychology, 108(1), 211-219. Hampshire, A., Gruszka, A., Fallon, S. J., & Owen, A. M. (2008). Inefficiency in self-organized attentional switching in the normal aging population is associated with decreased activity in the ventrolateral prefrontal cortex. Journal of Cognitive Neuroscience, 20(9), 1670-1686. Miller, E. K., & Cohen, J. D. (2001). An integrative theory of prefrontal cortex function. Annual Review of Neuroscience, 24, 167-202. Milner, B. (1963). Effects of different brain lesions on card sorting: The role of the frontal lobes. Archives of Neurology, 9, 90-110.
Factors Affecting a Card Sorting Task 91 Set A (Control Cards): Appendix A Set B (Experimental Cards):