Studying Effect of Age on Ability to Ignore Distractions
Introduction
With aging, people tend to perform poorly on cognitive tasks as they are unable to ignore non-relevant information. At the same time, young adults are observed to be adept at ignoring irrelevant information as they seem to be more focussed and have the ability to ignore distractions. Research studies published so far are throwing highly contrasting results. Mack & Rock (1998) in studies related to inattentional blindness (IB) formulated a working hypothesis that there is no perception without attention, as young adults failed to respond or to remember information presented in the centre of their visual field.
This Paper is aimed at studying effect of age differences in the ability to ignore distraction using a task in which irrelevant information must be ignored – using an implicit measure of memory : a word fragment completion task without the participants being aware of the target words or re-use of previously presented material.
My hypothesis in this study: Age has a significant effect on person’s ability to ignore distraction.
The older the person is, lesser will be his/her ability to ignore distraction. Younger the person is, higher will be his/her ability to ignore distraction.
Method
Participants: There were 34 young university students (aged 18-30 years) and 34 older participants (aged 60-75), who were community-dwelling volunteers and were paid for participating in this study.
Material: Main data set for the study was select simple line drawings, chosen from a picture set developed by Snodgrass & Vanderwart (1980), overlaid with equal number of either random letter-strings or words.
Procedure: Experimental study consisted of two phases: study and test. During the study phase, participants viewed a sequence of individual pictures (presented for 1500ms at a time), some of which were superimposed with random letters, a filler word, or a target word.
Test phase: This involved word-fragment completion task followed by a picture-comparison task. The test phase began, after an interval of approximately 10 minutes during which participants completed an unrelated task. Out of the 30 word-fragments given to the participants, 10 were fragments of target words presented during the study phase, 10 were fragments of control words that were not presented, and 10 were easily solved fragments that served as fillers to ensure participants felt successful during the task. In this way the test tool obscured the connection between the study phase and test phase. Target and control words were counterbalanced equally between participants.
Tests used
Two tests were used in this study: Word-fragment completion test and Visual memory task. Word fragment completion test is chosen because it is easy to administer either in pencil-or-paper mode or online version and further such tests bring in a novelty for the participants by breaking the monotony of other tests and survey instruments. This test is one among many tools available for measuring implicit memory. In the visual memory task, participants were required to identify pictures which were repeated and then their ability to get distracted by the words embedded within the picture was also tested. In a study reported by Rowe, Valderrama, Hasher & Lenartowicz (2006), older adults showed greater implicit memory for previous distraction, which had occurred an on earlier 1-back test as irrelevant words superimposed on relevant pictures.
Age is a grouped variable (‘older’ and ‘younger’), while percentage of correct answers is a continuous variable. Hence robust statistical tests for this data cannot be conducted. Descriptive statistics for computing central measures of tendency and percentile distribution of correct answers are suitable, as they give a comparative picture about the performance of two groups in the experimental tests.
Results
Data related to - ‘age’ (independent variable) and ‘percentage of correct answers’ (dependent variable) of 68 participants- is collected in this study. Participants belonged to two groups ‘older’ and ‘younger’ were equal in number. The test scores as measured by the percentage of marks for the two groups are given in Fig 1 (appended at the end) and Table 1.
Descriptive statistics, indicating measures of central tendency for the two groups of participants are given in Table 2. Percentile distribution of ‘% of correct answers’ given by participants is indicated in Table 3.
Bi-variate correlation was used to check whether ‘percentage of correct answers’ is related to the age of participants. Test results are given in Table 4.
Discussion
Interestingly, the older group of participants had higher mean percentage of correct answers 56.86, as compared to a lower mean of 36.52 per cent for younger participants. Standard error of mean, standard deviation and variance for the younger group was higher than the corresponding values for the older group. These higher values indicate the wider scatter of sample mean from the population mean for the younger group. In the context of this study, the younger participants seem to be afflicted with inattentive blindness and since they do not pay attention, there is no perception about the critical clues given in the two phases of the test hence majority of them lower values of ‘% of correct answers’
28 participants belonging to the younger group provided correct answers within the band of 16.67 to 50 per cent, while only 16 older participants could fall within this bracket. Coming to the band of above 50 per cent, i.e. 58.33-91.67, only six younger participants (17.6% of the younger group) fell in this band, while 18 older participants (52.9% of the older group) were able to achieve this higher scale. Older participants correctly answering (above 50% of questions correctly) were three times more than the younger participants. This is an interesting result which shows that older people are not inattentive in spite of their age, and many of them could recollect from memory.
Correlation test shows that ‘Percentage of correct answers’ is moderately related to ‘age group’ and the relationship is negative. In other words, as the age advances, percentage of correct answers goes up; while younger adults are likely to score lower percentage. This means that ability to ignore distractions does not come down with aging. Younger people get distracted and score lower in percentage of correct answers.
Conclusions
Results reveal that the hypothesis formulated in this study: “Age has a significant effect on person’s ability to ignore distraction” is not proved. Correlation test shows that the variables are negatively correlated i.e. the older the person is, higher will be his/her ability to ignore distraction. Younger the person is, lesser will be his/her ability to ignore distraction, which converges with Mark & Rock’s ‘inattentional blindness’ hypothesis. In other words, older group of participants have displayed higher level of implicit memory as compared to the young group.
The implicit memory levels of younger group, as measured by the percentage of correct answers might be due to several factors, major among which are: English may not be their native language; they are not exposed to larger vocabulary of words in English and their exposure to English literature may be less or their medium of instruction could be other than English.
Memory can be improved through several means: focussing on the task: either word completion (recall test) or elimination of duplicate pictures (recollection); picture identification (even though distractions are placed- recognition test); and by grouping the long phrases or words with some associations;
With a small sample size of 68 and grouped data (age), findings of this study cannot be generalized. Further studies are needed involving larger sample, rich data capturing different dimensions, such as demographics, time and day of the test and personality traits of participants.
References
Mack, A. & Rock, I. (1998). Inattentional blindness. Cambridge, MA: MIT Press.
Snodgrass, J.G. & Vanderwart, M. (1980). Norms for picture stimuli. Journal of
Experimental Psychology: Human Learning and Memory, 6, 205-210.
Rowe, G., Valderrama, S., Hasher, L., & Lenartowicz, A. (2006). Attentional disregulation:
A benefit for implicit memory. Psychology and Aging, 21, 826-830.
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