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2 Solutions If employers know about or had access to the information reviewed at the conference, they would be able to unprove or introduce programs that take into account the changing vision capabilities of their workers. The preceding section described work that needs to be done by the scientific and business communities before such programs can be put into place in their entirety. But employers need not wait. There are many steps that could be taken now to improve the performance of workers based on current knowledge. This section identifies some of the possi- bilities raised by conference participants, which include providing suitabIc sometimes very inexpensive visual aids for older work- ers; providing opportunities for training and retraining on the job; raising illumination; introducing other selected modifications in the design of the work environment; adopting certain avail- able screening procedures; and redesigning jobs. Taken separately or together, these actions could bring enormous returns to both workers and employers. COMPENSATING FOR DECLINING VISUAL FUNCTION In 1890 William James published a psychology text that even now, nearly a century later, contains many powerful insights. Among them ~ a proposed general law of perception: Whilst part of what we perceive comes through our senses from the object before us, another part (and it may be the larger part) always comes out of our own mind." 28
29 Though one may not agree with James's claimed proportions- it may not be the larger part of perception that comes out of our own mmdsit ~ hard to deny that the act of seeing draws on far more than just the neural information that ~ momentarily avail- able from st~rnulating the eyes. A number of studies suggest that the past experiences that older people are able to draw on in the performance of certain tasks may overcome certain age effects in visual function. Practice ~ the principal agent creating important skill differences between experienced and inexperienced workers. And the expertise that comes with practice ~ certainly among the older worker's strong suits. One such study, reported by Salthouse, examined transcrip- tion typing, that is, typing from printed copy.6 This is an interest- ing activity from our current perspective because there is a large number of typists at many leveb of experience at all ages, and typing is a perceptual-motor skill that laboratory results suggest declines with age. However, the Salthouse study yielded some surprising results. Typists ranging from 19 to 72 years of age and with a range of typing speed from 17 to 104 net words per minute participated in a series of typing-like tasks. The sample was deliberately selected to result in a near-zero correlation between age and typing skill because the primary research question was not whether typing speed declined with age, but rather what were the differences between typists of different ages with the same overall level of skill. Two of the initial measures obtained from each participant were the average time between successive keystrokes (interkey in- terval) while perfortn~ng normal typing, and the average time between keystrokes while performing a standard reaction time task. These activities are structurally quite similar in that both involve rapid keystroke responses to visually presented alphabetic characters, but the stimuli in the choice reaction tone task were presented discretely, with the next stimulus presented only after the response had been registered from the previous stimulus. The important finding to note from this study is that the age trends differ substantially for the two tasks despite considerable super- ficial similarity. Performance on the reaction time task exhibits 6 Salthouse, T.A. (1984), Effects of age and skill in typing. Journal of E~crimcntal Psychology: Gcncral 113:345-371.
30 quite typical age-related increases indicating poorer performance with increased age, yet performance of these same individuals on the typing task was virtually independent of age. Subsequent manipulations in the project were designed to ad- dress two questions: (~) Why ~ there no age trend in the speed of typing when there ~ a pronounced age trend among the same individuab in the speed of responding in reaction tune task? and (2) Why are people of all ages so much faster in their keystrokes in typing than in reaction tune? Tentative answers to these ques- tions came from a variation of the test, In which the number of preview characters in the display was systematically varied while typing; the average interkey interval was then measured as a func- tion of the size of the preview window. The results indicate that average interval between keystrokes increases as the number of visible characters decreases below about 7 characters. This fi~- ing suggests that skilled typists begin processing characters to be typed well in advance of the current character. In fact, if only a single character ~ presented and typists are prevented from using this type of anticipatory processing, performance closely resem- bles that characteristic of the reaction time task. An examination of the age trends on these measures suggested to Salthouse that older typists employed a form of anticipatory processing to com- pensate for their slower perceptual-motor processes. This finding resembles those of Czaja.7 Other types of compensatory skills were described at the con- ference by Morgan: When ~ go from outdoors to indoors, it takes me much longer than anybody else in my group to find out what's going on.... ~ am relatively more certain that ~ don't see as well anyway, no matter how weld ~ dark-adapt. ~ also notice that have some difficulty separating blue colors. ~ can't tell some- tunes whether the thing is lavender or pink. It so happens that in time ~ can arrive at the correct conclusion by introspection: if ~ am certain of the color, it's probably lavender; if I'm not certain, it's probably pink. ~ don't have as much trouble driving at night as one might think. Because ~ expect to have trouble driving at night, have cut down my night driving. But ~ have great difficulty 7 Czaja, S. and C. B. Drury (1981), Age and pretraining in industrial inspection. Nunwn Factors 23:485-494.
31 driving at twilight e In part, it is due to the fact I have great difficulty In visual search, in finding the particular area the scene that I want to pick out that makes sense to me. I've gotten into the habit of taking a dry run to somebody's home that I have never visited before. I will drive to it in the middle of the afternoon to find out where it is, so that I won't get lost getting there in twilight. The ability of older workers to develop compensatory skills and the role of practice should never be underestimated when considering visual changes among older workers. BETTER VISION SCREENING PROCEDURES Screening tests are often used to determine whether an indi- vidual's vision is adequate for a particular job. Vision screening procedures, however, "e often not very job specific. Kline reviewed a number of visual screening procedures that may be of interest to employers. In older workers, effective visual field size may be reduced, which argues for the inclusion of visual field tests in any screening procedure. At the present tune, a few states require a visual field determination for a driver's license. As Michaels pointed out, every patient should have visual field records, but this is not always practical. As visual field extent is shown to be of importance in jobs involving visual search, for example, or in information-dense scenes, visual field testing may become more desirable and thus a standard part of screening procedures for older workers. Many visual screening procedures that could be used by em- ployers are still In the experimental phase. The contrast sensitiv- ity function (CSF), for example, provides a more comprehensive statement of spatial vision abilities than do more traditional acuity measures, according to Kline. It does so by determining threshold contrast required to detect objects (typically gratings) by varying spatial structure (spatial frequency). It is likely that some work tasks depend more on intermediate spatial frequencies that are better assessed by the CSF than by standard acuity tests. Unfor- tunately, as Kline points out, although work is proceeding in this direction and test patterns are readily available, the diagnostic value of the CSF has yet to be demonstrated for such tasks.
32 Standard acuity testing gives little indication of a person's ability to distinguish detail in a rapidly moving object. More con- sideration should be given to tests to assess the visual fitness of older workers for tasks involving discrimination, such as occurs in driving or In ~moving-part" industrial operations. Such standard- ized tests have yet to be developed, however. As Michaels pointed out, the examination of the aging eye does not differ in essentials from that of any other eye except that it takes more time, more tact, and more patience. fit takes more time because older people frequently have many nonspecific complaints, poorly expressed, and sequentially muddled. Some symptoms may go unreported because of memory loss, fear, or indifference. It takes more tact because, in the nature of things, some senescent diseases are not only chronic but irreparable. It takes more patience because the aged eye often suffers multiple defects which must be sorted out. As more consideration is given to the introduction of more or different procedures to screen the visual capabilities of older workers, some thought will need to be given to the question of who wiD administer the tests and decide which tests are needed. A great deal of sensitivity should be applied in using procedures that may rame concerns about vision functions that heretofore have not been given much thought by most workers. PROVIDING VISUAL AIDS What simple changes might be made in the workplace in order to accommodate visually Unpaired workers? There are many simple magnification devices and techniques that can be put to use, such as a device to increase the relative size of the material to be used. Bruce Rosenthal illustrated the point that it ~ possible to be quite clever in meeting people's vision needs: ~ would like to tell you what happened with one of my patients who is 84 years old. He was flying out to the West Coast to work on a case. He ~ a lawyer, and it was a $350 million case. He said, ~I really would like to have some notes with me. What can ~ do? ~ don't want to use my lens because have to hold it up very close. He really didn't want to use his high-powered lens because he didn't want to have anybody
33 look at horn askance and think he really didn't know too much about the case. What we ended up doing was something very simple that everybody here can do. We got hold of one of the newer copiers which magnifies about 22 percent. We sent his notes through the copier once, a second time, then again. think we did it about 20 times. He ended up with a few letters on 11~ x I8~ size paper. That solved his problem. He brought reams of paper into the courtroom, and he won the case. Another technique involves moving the object toward the viewer's face, in effect, magnifying the image on the retina. There are high-powerec} reading spectacles that focus for a Chinch work- ing distance, although some people function much better using a hand magnifier. Stand magnifiers are devices that have plus lenses that are built into rigid housings. These are useful for arthritics or people who have a difficult time holding the lens steady, since the magnifier sits in a rigid housing. Genensky, In a paper prepared for the conference, also iden- tified the role of closed circuit television as a versatile visual aid currently available to partially sighted workers in some settings. Closed circuit television permits the control of the magnification of material seen on the screen as well as its brightness and contrast. Simpler nonoptical aids are also available. The typoscope LS certainly the simplest aid. This a piece of fairly stiff cardboard that is rectangular in shape and contains a rectangular slit or window in the middle. The typoscope is usually small enough to encompass all or a portion of a few lines of print when it Is placed on a page. Morgan observed: ~! very seldom find reported in the literature the problem of spatial interaction In reading printed material. It ~ the lack of border on the printed page as much as the fact that there ~ lack of space between the words and between the lines that makes it difficult to read. One of the solutions to the problem ~ a typoscope.... ~ need a white typoscope. ~ put it down on the paper, and ~ immediately increase the contrast between the print [and the background). Now ~ have a nice, white background, which allows me to figure out the line of print." In summary, many optical aids are available to augment de- clining sight.
34 RETRAINING OLDER WORMERS The compensations older people make in response to declin- ing sensory functioning suggest that learning, and therefore sys- tematic training or retraining programs, could be helpful with respect to the visual performance of older workers. To what ex- tent can training be used to approve performance directly through the development of compensatory strategies? Czaja reported at the conference that research has shown that appropriate training strategies can often enhance the task performance of older persons. Several studies have shown that a problem-solving discovery ap- proach that munimizes rote memory is effective for older learners. It is also important to provide learners with immediate feedback to maximize the unlearning of incorrect responses and also to give them enough time to avoid deleterious pacing effects. Successful learning is important both ~ its own right and in helping to avoid negative attitudes that act as a barrier to the acquisition of new skins. Learning and training are important areas to consider. And the issue of aging and training, which has not been examined very much from an industrial point of view, should be addressed from two different perspectives. The first is training in learning strate- gies. Czaja reported on evidence that suggests that the elderly are led likely to use cognitive strategies or learning strategies: Tithings like mnemonic aide and mediators and organizing learn- ing material. We have done some research on training older people to perform industrial inspection tasks. One thing we found was that providing them with Retraining on component skills that were relevant to the inspection task carried over later to subs quent inspection performance. We tried to provide pretraining and learning to learn kinds of skills, like organizing material, making size judgments, and the like." The second perspective concerns how to train people for spe- cific tasks. Czaja and her colleagues found that the success of older people In learning to perform new tasks or new jobs is highly de- pendent on the type of training method employed. "We certainly found this in our work when we looked at industrial inspection. We varied training. We used passive, traditional kinds of industrial approaches. We varied that with active, self-discovery feedback, and we found that this approach was superior. In fact, if people
35 were provided with that kind of training, they could successfully learn to perform those tasks. Czaja cautioned, however, that as people are being trained they are also forming attitudes about having to learn a new skill. "We did not find any age differences in attitude. We did find, however, that after training, people who reported a negative ex- perience in the training session and who felt that they did poorly had a significant change in attitudes and were not too keen on using [the new skiing. MODIFYING Tom: WORKPLACE In indoor office and factory workplaces the major limitation on visual functioning of older workers results from a relative lack of illumination of the unage on the retina. As Fozard reported to conferees, one study measured the time required by women in two age ranges from (1~27 years and 4~57 years) to complete a visual search task under three levels of illumination, 53S, 1,076 and 1,614 Jux. Performance times decreased with increasing levels of illumination in both age groups but more so for the older women. Other findings were that both groups expressed a preference for higher levels of illumination, and the older but not the younger women experienced greater eye comfort at the two higher levels. Adequate iBum~nation includes the ability to manipulate the lighting arrangement both to properly illuminate the object of visual attention and to control for glare. To achieve this it is necessary to provide workers with a degree of control over both generalusually ceiling illumination as well as local illurn~na- tion usually lamps~f smaller areas. Provision of this degree of control is necessary but may not be sufficient, inasmuch as most people are accustomed to thinking of lighting in terms of a fixed entity, such as ceiling fixture or a piece of furniture, that should not be moved around simply for functional convenience. For these reasons the opportunity to manipulate lighting sources should be supplemented with some training designed to show people how to manipulate the visual environment to their advantage. Environmental intervention can also mitigate the effects of age differences in adapting to changes in illumination. Changes that require shifts between very different levels of illumination can be especially difficult for older people. In raising light levels, however, it is important to avoid glare problems caused by creating
36 excessive differences In brightness. One way to achieve this is to provide workers with individual control over both general and local iBurn~nation levels. Video Replay terminal present special problems for the vision of older workers. With care, special glasses can be worn to brig the video screen to clearest focus for an individual, but commonly the keyboard and reference documents are located at other dis- tances. So the individual working at a video display workstation must either accept blurred vision or change posture in order to view the keyboard or the reference documents. Thoughtful work- place design or the use of trifocab or progressive focal lenses can reduce these problems. Working-~mtance problems are not just associated with video displays. Inspection of large diagrams or drawings, reference to large notice boards, and a multitude of various construction and manipulative tasks often require critical vision over a range of dif- ferent viewing distances. Such tasks often present serious difficul- ties to older bifocal wearers who must change their head position or posture when they change their viewing from one object distance to another. Some of these problems are intrinsically unavoidable, but in many cases specially designed spectacle lenses or redesign of the work task can make work more comfortable and efficient. Kosnik pointed out that dimly lit environments may differen- tially impair the performance of older workers. And older workers' performance will be doubly compromised if small-s~zed print, me- ters, label, scales, charts, etc., have to be read in poor or darn illumination. Older workers may have more difficulty reading or locating targets when the visual scene Is cluttered with other objects. As a result, visual acuity, assessed with one target at a tune or assessed with widely separated targetsmay not provide an accurate guide to the functional acuity that the older worker brings to the job. Pastalan offered a number of specific suggestions for enhancing the safety of older workers through appropriate environmental design. These include the use of sign systems that employ high contrast between symbol and background; the introduction of textured surfaces to reduce glare; the use of redundant cueing around machines and hazardous areas; the use of extreme contrasts in transitional zones (e.g., indoor-outdoor entrances); and the use of red-yellow colors where accents are required. Clearly, there is
37 no shortage of ideas for changes that can be made in the workplace to facilitate the work of people with visual deficits. JOB REDESIGN Despite its demands, paid work is a critical component of adult life, and finding ways of extending a work attachment for the visually impaired as well as for other workers ~ very ~rnportant. As Kahne pointed out, "Not only is it the customary source of economic support for individuals add their dependents, for many persons it makes possible valuable pension benefits and offers the only source of health insurance protection at reasonable cost prior to age 65. It often provides, as well, psychological support of 'community' and a sense of self-identity." Can part-time work ever be a viable alternative to meet the needs of older workers for whom vision problems significantly im- pede the performance of their tasks? There is a lack of information to answer that question, but Kahne observed that institutional change to extend work attachment for the visually impaired will not be easy. Nonetheless, part-time employment may well be one of the more desirable approaches to responding to the employment needs of older workers whose declining vision has become a serious impediment to their employability.