How age affects the speed of perception of computer

icons

學生：董瑩蟬

Purpose

• This paper want to investigate the visual search task performance on the different age group. It is contrast between the different icon size and spacing search time .

Reference• Normal aging of visual system

年份 學者 結果2000 A.J. Bron et al. The visual ability decreases with age.

1999 A. Guirao et al. The eye of modulation transfer function decline with age.

2001 A. Glasser et al. There is a declined of Light scatter in the lens, which reduced visual contrast.

2005 J.W Page et al. The colour discrimination performance decreases with age.

19931996

C.A. Curcio et al.S. pardhan et al.

The number of retinal ganglion cells decreases with aging, which decline the transmitted ability, and it has loser contrast sensitivity.

Reference• Visual search年份 學者 結果1999 M.E. Scheck et al. In the dual task, the visual tunnel become

narrower with older.

2002 E.T. Davis et al. There is a longer of search time in older .

19972002

A.T. Weford et al.T.A. Salthouse. et al.

The visual perceptual slower with older, and the motor and cognitive has the same result.

20012002

N. Charness et al.E.T. Davis et al.

The performance can increase with train in older.

20012001

N. Charness et al.S.J. Czaja et al.

The performance dose not eliminate the effect, even after training.

Method1.Subject

51 person (8M,43F),Five groupNo eye-disease and visual impairedHave use computer experience

2.EquipmentPrecision visionVistechPC ComputerSGI 1600SW LCD

Method3. Independent variables

Icon sizesSpacing

4.Dependent variablesSearch time

Method5.Process• Measure visual acuity and contrast sensitivity.• Two trains.• Visual search task.• When fined the different

icon Click the “icon”, no

different or no fined click “no”. • When subjects find two errors,

this task will finish.

500ms

800ms

Results

Results

Results

Results

Results• Mean search time for normal size and normal vision for age group

Group Mean (ms) S.D

20-29 6066 9892

30-39 5302 4277

40-49 4647 2697

50-59 12019 11593

60-69 6436 4154

Results

Discussion

年份學者 得到結果 本實驗結果

2000 T.A. Sathouse The cognitive processing speed slower with aging.

The visual search speed increased with aging.

1997 N. Walker et al. The older spend more time to chick the mouse

cursor.

2003 R. Nasanen et al. There is a bad affect in search performance, when reduce the icon contrast.

Discussion

• The older has poor attention resources. (P.A. Reuter-Lorenz 2002)

• The older adults has less visual field. (G. Haegerstrom-Portony et al.,1999)

• The useful field of view reduce with aging. (J. Cerella,1985)

• The visual field become narrower with aging. (J. Cerella,1985; G. Haegerstrom-Portony et al.,1999)

Conclusions• The search time declined with increase

age.

• The interfere increase with the subnormal vision person, when the small icon and the far spacing.

• People with subnormal vision has no difference with normal person, when the large icon.

• The interface design degree about 1 and the spaced must be next to each other.