INDIAN PSYCHOSOCIAL FOUNDATION
 
   INDIAN PSYCHOSOCIAL FOUNDATION
         
IJPS >
IJPS April 2011
IJPS October 2011
IJPS April 2012
IJPS October 2012
IJPS April 2013
IJPS October 2013
IJPS Apirl 2014
IJPS October 2014
IJPS Apirl 2015
IJPS Apirl 2016
IJPS October 2016
IJPS Apirl 2017
 
 
 

AGEING AND ATTENTION: AN OVERVIEW

Richa Singh

Assistant Professor Department of Psychology

Vasanta College for Women, Rajghat Fort

Varanasi

 

Abstract

Attention appears to be the integral component of most cognitive tasks.  It is a necessary component of many everyday skills such as driving, conversing in noisy environment, searching for a friend in crowd or interacting with technology (e.g., websites, ATMs).  As the population of older people is growing rapidly, it has become increasingly necessary to examine how attention function changes with age and to understand the extent to which these changes can affect their functioning.  Measuring attentional abilities among older adults would allow prediction of continued success with tasks of everyday life.  Some researches have shown that different types of attention (selective, divided and sustained) decline with ageing when demands on attentional tasks are increased.  This paper presents an overview of researches done to assess the attentional ability in young and old adults.

Key words: Attention, Ageing, Selective attention, Attentional capacity, sustained attention.

Introduction

Healthy ageing is accompanied with a number of cognitive changes.  These include decline in functions such as episodic and working memory, attention and inhibition.  Among these cognitive changes attention is considered to be the fundamental component as it is gateway to rest of the cognition.  Information processing theories of cognitive ageing suggested that attention deficits could be the source of all or most age related changes in cognition.  Different types of attention (selective, sustained, and divided) have been found to decline with ageing.  Deficiency in attentional resources has been postulated as important in ageing leading to inefficiencies rather than losses of functions.  It has become increasingly necessary to examine how attentional ability changes with age and to understand the extent to which these changes can affect the functioning of rapidly growing older adult population. 

Ageing and Attention

Attention is a necessary component of everyday skills that require search and prioritization of information such as driving or interacting with technology (e.g., websites, ATMs); measuring attentional abilities among older adults would allow prediction of continued success with tasks of everyday life.  Attention is a cognitive process that helps in complex interaction with the environment by picking up the relevant information while ignoring the irrelevant ones.  Processing one source of information at the expense of others is the “selective” function of attention; simultaneous processing of two or more sources of information is the function of “divided attention” and maintaining a consistent focus on one source of information is the function of “sustained attention”.

Studies designed to understand the age related changes underlying attentional abilities show that normal aging results in loss of attentional capacity 1, 2, 3 typically, the observed effects of aging on attention are modest, and deficits are apparent only under circumstances of high attentional demands 4, 1, 5.  A number of studies suggested that attention diminishes in old age, as the tendency for attention to wander begins 2, 6, 7,.  For example, one of the most popular theories used to explain attention and aging, postulates that with age attention declines because of the increasingly inefficient operations of an inhibitory mechanism that that helps to suppress irrelevant information 8, 9.  Research on visual attention processes and aging has focused on selective attention, attentional capacity (divided attention) and sustained attention.

Aging and Selective Attention

Selective attention is the mechanism in which the resources are directed toward relevant stimuli while ignoring the irrelevant information in order to meet effectively with task such as driving, conversing in noisy environment or searching for a friend in crowd.  Visual search task is generally employed to examine the age related attentional change.  Visual search task requires subjects to detect target items in a visual display.  The typical finding in a visual search task is that as the display size increases, there is a linear increase in RT 10.  Previous researches have reported both deficit as well as age constancies in selective attention. 

Evidence for age related selective attention deficits come from the studies which demonstrated an age related deficits in the ability to ignore irrelevant or interfering information 11,12,13,14.  Rabbit conducted the early investigation for age differences in selective attention and concluded that older subjects had difficulty ignoring irrelevant information and were at disadvantage when searching complex stimuli.11 another study   provided further evidence for age related deficit in selective attention. 13  They used two conditions of search i.e. feature search and conjunction search and demonstrated that the older adults were at a disadvantage relative young adults in the conjunction search condition.  Search RT in the feature search condition was fairly constant over display size for both young and old.  It was concluded that age differences in the conjunction search condition was the result of increased attentional demands of selecting the appropriate target and avoiding the interference from similar non target features.

Evidence for age constancies in selective attention has also been reported.  In a study Nabes compared young and old adults who were required to respond “yes” or “no” regarding the presence of a prespecified target in a visual display of six digits. 15 On half of the trials a valid visual cue was presented 1sec. prior to the display onset and on remaining half of the trail an invalid cue was presented 1sec. prior to the display onset.  Result demonstrated that decrease in RT associated with cue was equivalent for both young and older adults suggesting that the older adults were as effective as the young adults in using the cue to attend selectively to the relevant display items 16.  Thus, advance knowledge about target location can reduce the negative impact of distracters of older adults.

Aging and Attentional Capacity

Attentional capacity refers to the limited amount of processing resources that underlie task performance 16.  With regard to attentional capacity researches have focused on divided attention or dual task performance.  It has been assumed that the need to divide the limited pool of attentional resource between two task is more detrimental for older than to younger adults due to a reduction in cognitive resource with increasing age. 

Dual tasks have been used to investigate age related changes in attentional capacity.  The findings from such studies have demonstrated that the impairment of performance associated with dual condition is greater for older adults than for young adults 17.  Numerous studies in cognitive aging research have shown that as the complexity of the task increases, the magnitude of the age difference in performance also increases 18, 19, 20, 21.  Nestor, Parsuraman and Haxby used probe RT task paradigm in young and old adults to evaluate the “cost” of both automatic and controlled mental processes.  Results demonstrated that older adults showed increased attentional cost for both automatic and effortful mental operations compared to young adults.

These results can be explained from the assumption that there is fundamental resource (cognitive capacity) and this resource is reduced in old age.  Dual tasks require division of attention between two simultaneous tasks.  If cognitive capacity of elderly subjects is reduced, then primary task requires greater proportion of the available resource leaving less for secondary task and thus leading to poorer secondary task performance in older tan in young adults.

Ageing and Sustained Attention

Sustained attention or vigilance refers to the ability to detect small changes occurring at random intervals in the environment 22.  The fundamental problem with sustained attention or vigilance is the decrement function.  Vigilance decrement is the decline in the detection rate of critical targets with time on task.  Studies of sustained attention distinguish between overall vigilance, reflecting overall level of performance on sustained attention task, and the vigilance decrement, reflecting the ability to sustain attention over time on task 23.

Laboratory studies of sustained attention in older persons yielded conflicting results. Several studies found that sustained attention of young and older persons on vigilance tests did not differ 24, 25, 26, 27, and 28; while other studies showed that the vigilance performance of elder person was less efficient than that of younger persons 29, 30, 31, 32, 33, 34.

The clock test for 1 hour to study sustained attention in normal aging and found overall decrease in detection (hits) rates in old relative to young subjects.32 older subjects had equivalent increase in response time than young subjects.  Several studies indicate that aging is generally associated with increase in response criteria 35, 36, and that older subjects become more conservative over time on task than the young.  Pars Raman, Nestor and Greenwood 37 used the vigilance task with degraded stimuli while Berardi, Parsuraman, and Haxby 3 used high event rate digit discrimination task at six levels of stimulus degradation to investigated age differences in sustained attention.  These studies provided evidence in support of the view that overall level of sustained attention are lower in older individuals than they are in young individuals as the processing demands of vigilance tests are increased by varying event rate and stimulus degradation.

Researchers have explained this inconsistency in findings regarding sustained attention and aging as the result of a number of factors.  Researches suggested that the rate of stimulus presentation and the stimulus quality influence performance significantly among older individuals 38, 39, 1, 37, 40.

Theoretical explanations Proposed

Many theoretical explanations have been proposed for age differences in attentional processes and age related differences in attentional functioning. 41 The first theory proposes that with increased age comes a reduction in energy that fuels cognitive processing.  Thus, attention is a resource that enables cognitive processing and this resource is diminished with advanced age.  Second theory proposes that older adult exhibit reduced inhibitory functioning. 42 Attentional deficiencies in older adults are due to a filtering decrement, resulting in increased levels of intrusions and distractions from irrelevant stimuli.  The third theoretical consideration explains age differences in attention by a generalized slowing model or by the consideration of a reduction in the size of older adult’s functional visual field 43.  Those who posit a generalized age related slowing argue that age related attentional effects are expressions of a general slowing of all cognitive operations with advanced age 18, 42, 19, 45.

Conclusion

In summary, it can be concluded that attentional capacity is affected by ageing which is manifested in terms of inefficiencies in their functioning.  Typically, the observed effects of aging on attention are modest, and deficits are apparent only under circumstances of high attentional demands.  Selective attention seems to decline with ageing but advance knowledge about target location can reduces the negative impact of distracters.  An attentional capacity or divided attention appears to be most affected by the ageing process while studies of sustained attention in older persons yielded conflicting results.  The inconsistencies in the findings can be attributed to differences in methodologies used in different researches.  Various theoretical accounts have also been proposed to explain these results but this area needs more extensive explorations to understand the changes in attention as the person grows older.

References

 

1.        Parsuraman, R & Giambra, L. Skill devlopment in vigilance: Effect of event rate and age. Psychology and Ageing, (1991).  6, 155-169.

2.        Greenwood, P. M., Parsuraman, R. & Alexander, G. E. Controlling of focus of spatial attention during visual search: Effects of advancedd aging and Alzheimer’s disease. Neuropsychology, (1997). 11, 3-12.

3.        Berardi, A. M., Parsuraman, R., & Haxby, J. V. Overall vigilance and sustained attention decrement in healthy aging. Experimental Aging Research, (2001). 27, 19-39.

4.        Parsuraman, R., Nestor, P., & Greenwood, P. M. Sustained attention capacity in young and older adults. Psychology and Aging, (1989).  4, 339-345.

5.        Mouloua, M. & Parsuraman, R. Aging and Cognitive vigilance: Effect of spatial uncertainity and event rate. Experimental Aging Research, (1995). 21, 17-32.

6.        Langely, L. K., Overmier, J. B., Knopman, D. S. & Prod’Homme, M. M. (1998). Inhibition and habituation: Preserved mechanism of attentional selection in aging and Alzheimer’s disease. Neuropsychology, 12, 353-366.

7.        McDowd, J. M. & Filion, D. L. Aging, selective attention, and inhibitory processes: a psycho physiological approach. Psychology and Aging, (1992).  7(1), 65-71.

8.        Hasher, L., Zacks, R. T., & May, C. P. (1999). Inhibitory control, circadian arousal, and age. In D. Gopher & A. Koriat (Eds.) Attention and performance XVII: Cognitive regulation of performance (pp. 653- 675). Cambridge, MA: MIT Press, Bradford Books.

9.        Zacks, R. T., Radvansky, G., & Hasher, L. Studies of directed forgetting in older adults. Journal of Experiment Psychology: Learning, Memory, & Cognition, (1996). 22, 143-156.

10.     Treisman, A Strategies and models of selective attention. Psychological Review,(1969). 76, 282-299.

11.     Rabbit, P. Set and age in choice response task. Journal of Gerontology (1964). 19, 301-306.

12.     Rabbit, P. Age and discrimination between complex stimuli. In A. T. Welford & J. E. Birren (Eds.) Behavior, ageing and the nervous system, (1965). (pp. 35-53), Charles C. Thomas, Springfield, IL.

13.     Plude D. J. & Doussard-Roosevelt, J. A. Ageing, selective attention and feature integration. Psychology of Ageing, (1989).  4, 98-195.

14.     Allen, P. A., Madden, D. J. Groth, K. E. & Crozier, L. Impact of age, redundancy, and perceptual noise on visual search. Journal of Gerontology: Psychological Science, (1992).  47(2), 69-74.

15.     Nebes, R. D. & Madden, D. J. The use of focused attention in visual search by young and old adults. Experimental Ageing Research, (1983) 9, 139-143.

16.     Madden, D. J Adult age differences in attentional selectivity and capacity. European Journal of Cognitive Psychology, (1990).  2, 229-252.

17.     Groth, K. E. & Allen, P. A. Visual attention and aging. Frontiers in Bioscience (2000). 5, 284-297.

18.     Cerella, J. Information processing rate in the elderly. Psychological Bulletin, (1985b).  98, 67-83.

19.     Salthouse, T. A. Speed of behavior and its implications for cognition. In J. E. Birren, & K. W. Schaie (Eds.) The Handbook of Psychology of Ageing, (1985). (pp. 400-426), Van Nostrand Reinhold, NY.

20.     Brinley, J. F. Cognitive set, speed and accuracy of performance in the elderly. In A. T. Welford & J. E. Birren (Eds.) Behavior, Ageing and the Nervous System, (1965).  (pp. 114-149).

21.     Cerella, J. L., Poon, L. W. & Williams, D. M. Age and the complexity hypothesis. In L. W. Poon, (Ed.) Ageing in the 1980s: Psychological issue, (1980).  (pp. 332-340).

22.     Mackworth, N. H. The breakdown of vigilance during prolonged visual search. Quarterly Journal of Experimental Psychology, (1948). 1, 6-21.

23.     Davies, D. R., & Parsuraman, R. The psychology of vigilance. (1982). Academic Press, London.

24.     Davies, D. R. & Griew, S. A further note on the effect of aging on auditory vigilance performance: the effect of low signal frequency. Journal of Gerontology, (1963).  18, 370-371.

25.     Griew, S. & Davies, D. R. The effect of ageing on auditory vigilance performance. Journal of Gerontology, (1962).  17, 88-90.

26.     Neal, G. L. & Pearson, R. G. Comparative effect of age, sex and drug upon two tasks of auditory vigilance. Perceptual and Motor Skills, (1966). 23, 967-974.

27.     Tune, G. S. Age differences in error commission. British Journal of Psychology, (1966). 57, 391-392.

28.     York, C. M. Behavioral efficiency in a monitoring task as a function of signal rate and observer age. Perceptual and Motor Skills, (1962). 15, 404.

29.     Davies, D. R., Age differences in paced inspection tasks. In G. A. Talland (Ed.) Varities of attention (1968).  (pp. 395-447). NY: Academic Press.

30.     Davies, A. D. & Davies, D. R. The effect of noise and time of day upon age differences in performance at two checking tasks. Ergonomics, (1975). 18, 321-336.

31.     Harkins S. W., Nowlin, J. B., Ramm, D. & Schroeder, S. Effect of age, sex and time on watch on a brief continuous performance task. In E. Palmore (Ed.) Normal Aging II (1974). (pp. 140-150). Durham, NC: Duke University Press

32.     Surwillo, W. W. & Quilter, R. Vigilance, age and response time. The American Journal of Psychology, (1964). 77, 614-620.

33.     Tallland, G. A. Visual signal detection as a function of age, input rate and signal frequency. Journal of Psychology, (1966).  63, 105-115

34.     Thompson, L. W., Opton, E. J., &Cohen, L. DEffect of age, presentation speed, and sensory modality on performance of a “vigilance” task. Journal of Gerontology, (1963). 18, 366-369.

35.     Botwinick, J. Ageing and behavior. Springer, NY. (1984).

36.     Okun, M. A. Adult age and cautiousness in decision: A Review. Human Development, (1976). 19, 220-233.

37.     Parsuraman, R. & Mouloua, M. Interaction of signal discriminability and task type in vigilance decrement. Perception and Psychophysics, (1987). 41, 17-22.

38.     Bunce, D. J. Age differences in vigilance as a function of age related physical fitness and task demands. Neuropsychologia, (2001). 39, 789-798.

39.     Deaton, J. E. & Parasuraman, R. Sensory and cognitive vigilance: Effects of age on performance and subjective workload. Human Performance, (1993). 6, 71-97.

40.     Rueckert, L. & Grafman, J. Sustained attention deficit in patients with lesion of posterior cortex. Neuropsychologia, (1998). 36, 653-660.

41.     Hartely, A. A. Attention. In F. I. M. Craik & T. A. Salthouse (Eds.) the Handbook of Ageing and Attention, (1992). (Pp-3-49). Lawrence Erlbaum, NJ.

42.     Hasher, L. & Zacks, R.T. (1988). Working memory comprehension and ageing. In G. H. Bower (Ed.) the Psychology of Learning and Motivation, (pp. 193-225), Academic, San Diego.

43.     Cerella, J. Age related decline in extrafoveal letter perception. Journal of Gerontology, (1985a).  40, 727-736.

44.     Hale, S., Meyerson, J. & Wagstaff, D. General slowing of nonverbal information processing: Evidence for power law. Journal of Gerontology, (1987).  42, 131-136.

45.     Scialfa, C. T. Adult age differences in visual search: The role of non-attentional factors. In J. T. Enns (Ed.) The Development of Attention: Research and theory (1990).  (pp. 509-526), North Holland, Amsterdam.