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Adulthood Aging: Normal Effects on Visual Function Goal: Understanding of the normal degradation of numerous visual functions, including the underlying.

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Presentation on theme: "Adulthood Aging: Normal Effects on Visual Function Goal: Understanding of the normal degradation of numerous visual functions, including the underlying."— Presentation transcript:

1 Adulthood Aging: Normal Effects on Visual Function Goal: Understanding of the normal degradation of numerous visual functions, including the underlying sensory processes, that gradually occur during adulthood. This understanding is necessary for proper clinical examination, diagnosis of age-normal versus pathological change, and patient counseling. Schwartz pages 372 – 378 Optical, neurophysiological and psychological changes combine to detrimentally effect monocular sensory processes. Adulthood Aging: Normal Effects on Visual Function Goal: Understanding of the normal degradation of numerous visual functions, including the underlying sensory processes, that gradually occur during adulthood. This understanding is necessary for proper clinical examination, diagnosis of age-normal versus pathological change, and patient counseling. Schwartz pages 372 – 378 Optical, neurophysiological and psychological changes combine to detrimentally effect monocular sensory processes. EW8250F07

2 Adulthood Aging There has been understandably less focus on normal aging changes in visual function and enormous focus on eye diseases typically seen in older adults. Nonetheless, the vision changes produced by the former are often similar, albeit smaller, thus accurate diagnosis requires a working knowledge of these changes. Age ≥ 85: fastest growing segment of the US population. Adulthood Aging There has been understandably less focus on normal aging changes in visual function and enormous focus on eye diseases typically seen in older adults. Nonetheless, the vision changes produced by the former are often similar, albeit smaller, thus accurate diagnosis requires a working knowledge of these changes. Age ≥ 85: fastest growing segment of the US population. EW8250F07

3 Adulthood Aging: Normal Effects on Visual Function List of Topics Optical Changes Pupil, cornea, lens, vitreous Neurophysiological Changes Retina, cortex Psychological Changes Criterion Affected Sensory Processes Dark adaptation, acuity, acuity photostress recovery, MTF, spatial CSF, temporal CSF, visual field, useful visual field, color perception, refractive error, accommodation, motion, stereo acuity, acuity disability glare, and SCE-I. Adulthood Aging: Normal Effects on Visual Function List of Topics Optical Changes Pupil, cornea, lens, vitreous Neurophysiological Changes Retina, cortex Psychological Changes Criterion Affected Sensory Processes Dark adaptation, acuity, acuity photostress recovery, MTF, spatial CSF, temporal CSF, visual field, useful visual field, color perception, refractive error, accommodation, motion, stereo acuity, acuity disability glare, and SCE-I. EW8250F07

4 Adulthood Aging: Decreased Pupil Size (Senile Miosis) Large data spread but does show a decrease in pupil size with age. As expected, the decrease is larger (steeper slope) for very dim lighting. Very dim lighting, ~3 mm change. Very bright lighting, ~1 mm change. Clinical Implications Tests and refraction in dim lighting. Advising regarding optimal lighting. Expect a fixed 3–4 mm pupil by ~80. Also pupil reaction speed decreases. Ref-1 EW8250F07

5 Adulthood Aging: Decreased Pupil Size (Senile Miosis) Both iris sphincter and dilator muscles weaken. Increased inhibitory input to EW nucleus (parasympathetic). In total results in miosis and slower constriction and dilation. Produces symptoms of vision being ‘less bright’, initial ‘dazzle’ to outdoor light and difficult transitioning from light to dark areas. Adulthood Aging: Decreased Pupil Size (Senile Miosis) Both iris sphincter and dilator muscles weaken. Increased inhibitory input to EW nucleus (parasympathetic). In total results in miosis and slower constriction and dilation. Produces symptoms of vision being ‘less bright’, initial ‘dazzle’ to outdoor light and difficult transitioning from light to dark areas. Two Benefits: Reduced pupil-dependent aberrations. Not equal to the detrimental effects from reduced retinal illumination, lens-induced increases in light scatter, absorption and aberrations, and both retina and cortex aging. Increased depth of field. Results in less dependence on glasses during high illumination conditions. Ref-7 Line Spread Function for various pupil sizes EW8250F07

6 Adulthood Aging: Decreased Pupil Size (Senile Miosis) Detriment: Reduces retinal illumination thus also VA, CSF, etc. Average pupil size: age 20 = ~5 mm, age 60 = ~3 mm. Retinal Illuminance = Luminance (pupil area) = L(  r 2 ). As = 6, and = 2, retinal illuminance reduces by a factor of year old experiences age 60 trolands via ND 0.48 filter (log(1/.33)). Adulthood Aging: Decreased Pupil Size (Senile Miosis) Detriment: Reduces retinal illumination thus also VA, CSF, etc. Average pupil size: age 20 = ~5 mm, age 60 = ~3 mm. Retinal Illuminance = Luminance (pupil area) = L(  r 2 ). As = 6, and = 2, retinal illuminance reduces by a factor of year old experiences age 60 trolands via ND 0.48 filter (log(1/.33)). Ref-2 } 10x factor 3x factor (~2 lines) ~10 & ~30 trolands EW8250F07

7 Adulthood Aging: Decreased Transmittance (T) Normal sclerosis, largely from UV light absorption, results in further UV absorption, a yellow appearance, decreased color perception and decreased retinal illuminance. Adulthood Aging: Decreased Transmittance (T) Normal sclerosis, largely from UV light absorption, results in further UV absorption, a yellow appearance, decreased color perception and decreased retinal illuminance. Ref-1 Reduced T begins at age ~20 (adult). Visible wavelengths are all absorbed. Ultraviolet light is maximally absorbed by age ~45 whereas short visible (blue) wavelengths are similarly absorbed by age ~70. EW8250F07

8 Adulthood Aging: Decreased Transmittance (T) Nuclear sclerosis is at most a pre-cursor to nuclear cataract. Clinical learning involves the lens appearance for cataract diagnosis. Loss of corneal clarity (small effect) & vitreous debris can decrease T. Nuclear sclerosis is also shown by changes in index and surface radii: Adulthood Aging: Decreased Transmittance (T) Nuclear sclerosis is at most a pre-cursor to nuclear cataract. Clinical learning involves the lens appearance for cataract diagnosis. Loss of corneal clarity (small effect) & vitreous debris can decrease T. Nuclear sclerosis is also shown by changes in index and surface radii: Ref-1 Large changes by age 40. Anterior radius steepens. Posterior radius steepens. Thus thickness increases. Thus AC depth decreases. Refractive index decreases. Optical density increases. Total lens power decreases. EW8250F07

9 Adulthood Aging: Retinal Changes (Physical) Gradual loss of photoreceptors; rod loss >> cone loss. Reduced density of foveal cones. Reduced density of photopigment. Misalignment or improper orientation of cone outer segment. (Though not shown psychophysically by SCE-I.) Decrease in membrane resting potential (net hyperpolarized). Could lead to decreased photoreceptor response amplitudes. Decrease in neurotransmitter levels. Small but gradual loss of ganglion cells. Reduced mfERG: optical factors if age 70 (cone and bipolar cells contribution) Adulthood Aging: Retinal Changes (Physical) Gradual loss of photoreceptors; rod loss >> cone loss. Reduced density of foveal cones. Reduced density of photopigment. Misalignment or improper orientation of cone outer segment. (Though not shown psychophysically by SCE-I.) Decrease in membrane resting potential (net hyperpolarized). Could lead to decreased photoreceptor response amplitudes. Decrease in neurotransmitter levels. Small but gradual loss of ganglion cells. Reduced mfERG: optical factors if age 70 (cone and bipolar cells contribution) EW8250F07

10 Adulthood Aging: Central Changes Similar to physical changes in the retina… Small but gradual loss of neurons. Decrease in neurotransmitter levels, excitatory > inhibitory. Decrease in amount and weighting of binocular connections. Decrease in neuron tuning with associated increase in noise. LGN cell function is unchanged based on monkey physiology. Thus suggesting cortex as the site of major neural changes. Adulthood Aging: Central Changes Similar to physical changes in the retina… Small but gradual loss of neurons. Decrease in neurotransmitter levels, excitatory > inhibitory. Decrease in amount and weighting of binocular connections. Decrease in neuron tuning with associated increase in noise. LGN cell function is unchanged based on monkey physiology. Thus suggesting cortex as the site of major neural changes. EW8250F07

11 Adulthood Aging: Reduced Modulation Transfer Function (MTF) Ref-1 Image Contrast Object Contrast Reflects optical and neural contributions. Reduced transfer of object contrast for all spatial frequencies. Convincing contribution (non-pathological) to reduced visual acuity for ages ≥ 60–70. Functions calculated from empirical PSFs. 4 mm pupil used but relationship holds for all pupil sizes. EW8250F07

12 Adulthood Aging: Psychophysical Changes In order to not answer wrongly, patients adopt a strict criterion. Relevance to all subjective tests, including refraction and fields. Adulthood Aging: Psychophysical Changes In order to not answer wrongly, patients adopt a strict criterion. Relevance to all subjective tests, including refraction and fields. Ref-6 Psychophysics: Normal threshold for age but criterion gives a false high threshold. Normal or abnormal threshold for age but criterion gives a false high threshold due to less ‘hits’ reported. EW8250F07

13 Adulthood Aging: Psychophysical Changes To counteract a strict, or conservative, criterion: Encourage guessing; generally keep responsive. Adjust instructions and tone to allow for ‘mistakes’. Use a forced-choice procedure (i.e. forced response). Use discrimination tasks rather than detection tasks. Use the above methods beginning with entrance tests. Adulthood Aging: Psychophysical Changes To counteract a strict, or conservative, criterion: Encourage guessing; generally keep responsive. Adjust instructions and tone to allow for ‘mistakes’. Use a forced-choice procedure (i.e. forced response). Use discrimination tasks rather than detection tasks. Use the above methods beginning with entrance tests. Ref-6 EW8250F07

14 Adulthood Aging: Reduced Dark Adaptation Function shifts up and flattens beginning in early adulthood. Amount of reduction with age is non-proportional. Adulthood Aging: Reduced Dark Adaptation Function shifts up and flattens beginning in early adulthood. Amount of reduction with age is non-proportional. Ref-2 } Flatter slope throughout function, and flatter with age. Asymptote: Absolute sensitivity worsens with age. EW8250F07

15 Adulthood Aging: Reduced Dark Adaptation Mechanisms underlying upward shift of function: Higher (worse) absolute threshold: photoreceptor loss (rods > cones). Slower rate of adaptation: reduced rate of rhodopsin regeneration. Both of the above: optical changes, e.g. miosis, lens changes. Adulthood Aging: Reduced Dark Adaptation Mechanisms underlying upward shift of function: Higher (worse) absolute threshold: photoreceptor loss (rods > cones). Slower rate of adaptation: reduced rate of rhodopsin regeneration. Both of the above: optical changes, e.g. miosis, lens changes. Ref-2 Aged adults have more difficulty adapting to dark conditions than to light conditions. Elevated thresholds throughout function Maximum elevation: Cone portion 1 log unit Rod portion 2+ log unit EW8250F07

16 Adulthood Aging: Reduced Visual Acuity Normal acuity is maintained until age 65 – 70, then declines. From age 65 the link between VA and pathology is more difficult. Adulthood Aging: Reduced Visual Acuity Normal acuity is maintained until age 65 – 70, then declines. From age 65 the link between VA and pathology is more difficult. Ref-2 20/16 20/20 20/25 20/32 20/40 20/50 20/20, age ~65 20/25, age ~70 20/32, age ~75 Other studies find less loss: ~1 line/decade. EW8250F07

17 Adulthood Aging: Reduced Visual Acuity VA is a threshold measure so all optical and neural factors contribute. Reflected in effects of both reduced illumination and letter contrast: Marked VA reduction before age 65 – 70 that continues proportionally. Adulthood Aging: Reduced Visual Acuity VA is a threshold measure so all optical and neural factors contribute. Reflected in effects of both reduced illumination and letter contrast: Marked VA reduction before age 65 – 70 that continues proportionally. Ref-3 Ref-2 High Contrast and Luminance High Contrast, Low Luminance Low Contrast and Luminance Slightly unequal age onset and rate of decline. EW8250F07

18 Adulthood Aging: Reduced Visual Acuity VA test conditions / reason that older adults are very sensitive to: Luminance level /  retinal illuminance Letter contrast /  CSF Letter spacing /  crowding Criterion /  conservative Number of letters per size /  guessing Increment size of letters / if subnormal VA Improper testing often results in false VA loss in older adults. LogMar chart resolves some of these conditions. Adulthood Aging: Reduced Visual Acuity VA test conditions / reason that older adults are very sensitive to: Luminance level /  retinal illuminance Letter contrast /  CSF Letter spacing /  crowding Criterion /  conservative Number of letters per size /  guessing Increment size of letters / if subnormal VA Improper testing often results in false VA loss in older adults. LogMar chart resolves some of these conditions. EW8250F07

19 Adulthood Aging: Reduced Photostress Recovery Time Procedure: exposure to bright, diffuse light then wait for best VA. Results: age ≥ 60 shows non-linear increase in recovery time. Results: ~ 13–90 second recoveries; glare response to 20/200. Adulthood Aging: Reduced Photostress Recovery Time Procedure: exposure to bright, diffuse light then wait for best VA. Results: age ≥ 60 shows non-linear increase in recovery time. Results: ~ 13–90 second recoveries; glare response to 20/200. Ref-3 Mechanism Reduced letter contrast due to increased light scatter from miosis and lens changes. Natural Conditions oncoming headlights, flood lights, outdoor sun glare, streetlights. Relevance Exam sequence, therapy and counseling. EW8250F07

20 Adulthood Aging: Increased Disability Glare Veiling glare applied to acuity chart. A test of functional vision – conditions the same as for the photostress recovery test. Aids differential diagnosis of cataract disability. Some Commercial Equipment Miller-Nadler Glare Tester Mentor Brightness Acuity Tester (BAT) Berkeley Glare Test Straylightmeter CSV-1000 (VectorVision) MCT 8000 (Vistech) Mentor O&O Adulthood Aging: Increased Disability Glare Veiling glare applied to acuity chart. A test of functional vision – conditions the same as for the photostress recovery test. Aids differential diagnosis of cataract disability. Some Commercial Equipment Miller-Nadler Glare Tester Mentor Brightness Acuity Tester (BAT) Berkeley Glare Test Straylightmeter CSV-1000 (VectorVision) MCT 8000 (Vistech) Mentor O&O EW8250F07

21 Adulthood Aging: Reduced Spatial CSF Due to miosis, lens sclerosis, and neural aging (retina and central). Adulthood Aging: Reduced Spatial CSF Due to miosis, lens sclerosis, and neural aging (retina and central). Ref-2 CSF is relatively stable until 60’s then rapidly declines. CS to low spatial frequencies is always preserved. Thus quality of vision (CSF), as well as quantity (acuity), is reduced. Use for diagnosis and therapy. EW8250F07

22 Adulthood Aging: Reduced Spatial CSF Ref-8 20-year old can nearly mimic 60-year old CSF (reduced by 3x) via ND 0.48 filter. Filter simulates smaller pupil and lens changes. Sensitivity of low spatial frequencies are preserved. Counsel: use 3x normal lighting. EW8250F07

23 Adulthood Aging: Reduced Spatial CSF Ref-8 Adulthood changes do not result in the CSF of youth. Normal CSF, age 18–39. Youth CSF, age 8–15. reduced at all but high spatial frequencies. Adulthood CSF, age 45–66. Expect with further aging: Continued reduction of intermediate and high sf, and preservation of low sf. EW8250F07

24 Adulthood Aging: Reduced Spatial CSF Selected sensitivity loss suggests parvocellular > magnocellular loss. Also because this loss occurs under photopic and mesopic conditions. (Early age loss: increased aberrations & decreased retinal illuminance.) Adulthood Aging: Reduced Spatial CSF Selected sensitivity loss suggests parvocellular > magnocellular loss. Also because this loss occurs under photopic and mesopic conditions. (Early age loss: increased aberrations & decreased retinal illuminance.) Ref-2 Ref-7 Parvocellular component Magnocellular component EW8250F07

25 Adulthood Aging: Reduced Temporal CSF Shown for all temporal frequencies. Also, reduced high temporal frequency cut-off (CFF). Thus likely involves parvocellular and magnocellular neurons… With a contribution from decreased retinal illuminance. Adulthood Aging: Reduced Temporal CSF Shown for all temporal frequencies. Also, reduced high temporal frequency cut-off (CFF). Thus likely involves parvocellular and magnocellular neurons… With a contribution from decreased retinal illuminance. Ref-7 Entire function shifts down and in. Parvo = filled symbols Magno = open symbols EW8250F07

26 Adulthood Aging: Reduced Color Discrimination Shift towards blue-yellow (tritan) deficit. Primarily due to increased absorption by the lens. Secondary contribution from decreased retinal illumination. Secondary contribution from UV light induced retina damage. Minimal contribution from cone loss or photopigment change. Adulthood Aging: Reduced Color Discrimination Shift towards blue-yellow (tritan) deficit. Primarily due to increased absorption by the lens. Secondary contribution from decreased retinal illumination. Secondary contribution from UV light induced retina damage. Minimal contribution from cone loss or photopigment change. Ref-3 D-15 failure Is very high from age 65. EW8250F07

27 Adulthood Aging: Reduced Color Sensitivity Ref-5 Blue and violet light show the greatest rate of reduced sensitivity (> 2 log unit change). 40%–50% of reduction is due to lens sclerosis. Remaining reduction due to retinal change: damage > cone loss. Red and white light show ~ equal rates of reduced sensitivity (~ 0.5 log unit change). EW8250F07

28 Adulthood Aging: Reduced Limits of Visual Field (VF) VF continually decreases at 1–3 degrees per decade. This rate is only slightly increased by adulthood aging. Example:Widest horizontal VF extent: 170–180 degrees. Horizontal extent could reduce at age ≥ 70 to 130–140 degrees. Mechanism is both optical (degraded retinal image) and neural. Detrimental Implications: Visual attention Eye movements Motion detection Mobility Postural stability Adulthood Aging: Reduced Limits of Visual Field (VF) VF continually decreases at 1–3 degrees per decade. This rate is only slightly increased by adulthood aging. Example:Widest horizontal VF extent: 170–180 degrees. Horizontal extent could reduce at age ≥ 70 to 130–140 degrees. Mechanism is both optical (degraded retinal image) and neural. Detrimental Implications: Visual attention Eye movements Motion detection Mobility Postural stability EW8250F07

29 Adulthood Aging: Reduced Sensitivity of Visual Field Steady and similar decline throughout field; throughout adulthood. [note: decibel = (1/20)(log unit), so 6.67 dB = 0.3 log unit = 2x change] Adulthood Aging: Reduced Sensitivity of Visual Field Steady and similar decline throughout field; throughout adulthood. [note: decibel = (1/20)(log unit), so 6.67 dB = 0.3 log unit = 2x change] Ref-2 Each about 3 dB changes, thus a ~ 25% reduction through lifetime. Used in automated visual field programs. EW8250F07

30 Adulthood Aging: Reduction in Useful Visual Field (UVF) Ref-2 Not a conventional visual field. Rather, it’s attention-based: Identify (not detect) a foveal target while also identifying or detecting a peripheral target; dual divided attention task. A–D shows schematic of increasing useful VF reduction with age. EW8250F07

31 Adulthood Aging: Reduction in Useful Visual Field (UVF) Relevant for driving and mobility tasks. Counsel patients. Not a standard clinical test. Uses complex scenes as stimuli. Adulthood Aging: Reduction in Useful Visual Field (UVF) Relevant for driving and mobility tasks. Counsel patients. Not a standard clinical test. Uses complex scenes as stimuli. Ref-3 Slight reduction ~15 deg Large reduction ~100 deg Both start at age 50 – 60 EW8250F07

32 Adulthood Aging: Reduction in Useful Visual Field (UVF) Involves three independent processes within the visual field: Speed of information processing Ability to divide attention Salience of target to background Patients may have deficits in 1–3 processes. Effect is additive. Studies show UVF reductions of up to 85% in older adults. Might explain the increase in auto accidents with aging. (Traditional clinical measures do not, e.g. VA and CSF.) Adulthood Aging: Reduction in Useful Visual Field (UVF) Involves three independent processes within the visual field: Speed of information processing Ability to divide attention Salience of target to background Patients may have deficits in 1–3 processes. Effect is additive. Studies show UVF reductions of up to 85% in older adults. Might explain the increase in auto accidents with aging. (Traditional clinical measures do not, e.g. VA and CSF.) Ref-3 EW8250F07

33 Adulthood Aging: Refractive Error Shift Ref-1 Hyperopia prevalence at < age ~20 Myopic shift at age ~70 due to nuclear cataract Hyperopic shift after age ~40 from  lens power Refraction relatively stable at age ~20–40 EW8250F07

34 Adulthood Aging: Increased Against-The-Rule Astigmatism Astigmatism is predominantly with-the-rule (x180) up to age 40. Then the lens increases in dioptric power in the horizontal meridian. Thus a slow shift of with-the-rule to against-the-rule (x90) refraction. Also at > 40–45: small contribution from corneal shift towards A-T-R. Anticipate spherical and astigmatic changes for exam efficiency and proper diagnosis of age-normal versus pathologic condition. Adulthood Aging: Increased Against-The-Rule Astigmatism Astigmatism is predominantly with-the-rule (x180) up to age 40. Then the lens increases in dioptric power in the horizontal meridian. Thus a slow shift of with-the-rule to against-the-rule (x90) refraction. Also at > 40–45: small contribution from corneal shift towards A-T-R. Anticipate spherical and astigmatic changes for exam efficiency and proper diagnosis of age-normal versus pathologic condition. EW8250F07

35 Adulthood Aging: Reduced Accommodation Decreases steadily from youth but symptoms usually begin in mid-40s. Called presbyopia when decrease is associated with blur and eyestrain. Adulthood Aging: Reduced Accommodation Decreases steadily from youth but symptoms usually begin in mid-40s. Called presbyopia when decrease is associated with blur and eyestrain. Ref-1Ref-3 Rate of reduction is much greater at age < 50. EW8250F07

36 Adulthood Aging: Reduced Accommodation Ref-1 Mechanism Decreased elasticity of the crystalline lens capsule >> reduced ciliary body and zonular fibers function. Push Up Method Contaminated by angular magnification, depth of field, and subjective response. Stigmatoscopy Method Not affected by depth of field. Other two factors remain. Uses a point source conjugate to the retina to measure accommodative change for a separate accommodation target. EW8250F07

37 Adulthood Aging: Reduced Motion Detection and Discrimination Increase in the minimum displacement to detect coherent motion (Dmin). Decrease in the accuracy of discriminating direction of coherent motion. Loss of direction discrimination is worse than that for motion detection. Supported by macaque physiology showing age-related reduction in directional tuning by V1 neurons. Adulthood Aging: Reduced Motion Detection and Discrimination Increase in the minimum displacement to detect coherent motion (Dmin). Decrease in the accuracy of discriminating direction of coherent motion. Loss of direction discrimination is worse than that for motion detection. Supported by macaque physiology showing age-related reduction in directional tuning by V1 neurons. Ref-3 EW8250F07

38 Adulthood Aging: Reduced Motion Detection and Discrimination Mechanism is neural as both psychophysical and physiological studies used stimuli greatly above threshold (contrast & spatial frequency). Likely involvement of area MT or even higher-order motion areas. Detrimental Implications: mobility, driving, eye movements, dynamic VA. Adulthood Aging: Reduced Motion Detection and Discrimination Mechanism is neural as both psychophysical and physiological studies used stimuli greatly above threshold (contrast & spatial frequency). Likely involvement of area MT or even higher-order motion areas. Detrimental Implications: mobility, driving, eye movements, dynamic VA. Ref-9 EW8250F07

39 Adulthood Aging: Stiles Crawford Effect of the First Kind (SCE-I) Remains constant. Original study participants repeated at age 60s: no changes. Would change in response to pathology affecting pupil position. Apparently does not change in response to age-related aberrations. Adulthood Aging: Stiles Crawford Effect of the First Kind (SCE-I) Remains constant. Original study participants repeated at age 60s: no changes. Would change in response to pathology affecting pupil position. Apparently does not change in response to age-related aberrations. Ref-3 EW8250F07

40 Adulthood Aging: Reduced Stereoacuity Stereoacuity is the highest level of depth perception. It is a binocular rather than monocular process… But it requires optimal VA, cortical processing and eye alignment. Adulthood Aging: Reduced Stereoacuity Stereoacuity is the highest level of depth perception. It is a binocular rather than monocular process… But it requires optimal VA, cortical processing and eye alignment. Ref-3 85 arc sec criteria is not strict. Reduction begins at age ~50. That is, prior to normal reduction of visual acuity. Thus hinting at other mechanisms. EW8250F07

41 Adulthood Aging: Normal Effects on Visual Function Overview of Changes, Effects and Topics Optical: aberrations, absorption, light scatter, retinal illuminance Pupil, cornea, lens, vitreous Neurophysiological: absolute threshold, discrimination, rate of change Retina, cortex Psychological: threshold, variance Criterion Sensory Processes: reduction, alteration Dark adaptation, acuity, acuity photo-recovery, MTF, spatial CSF, temporal CSF, visual field, useful visual field, color perception, refractive error, accommodation, motion, stereo acuity, SCE-I. Adulthood Aging: Normal Effects on Visual Function Overview of Changes, Effects and Topics Optical: aberrations, absorption, light scatter, retinal illuminance Pupil, cornea, lens, vitreous Neurophysiological: absolute threshold, discrimination, rate of change Retina, cortex Psychological: threshold, variance Criterion Sensory Processes: reduction, alteration Dark adaptation, acuity, acuity photo-recovery, MTF, spatial CSF, temporal CSF, visual field, useful visual field, color perception, refractive error, accommodation, motion, stereo acuity, SCE-I. EW8250F07

42 Adulthood Aging: Clinical Relevance Acknowledging that people age at different rates, expecteds enable… Proper examination methods, including lighting, and sequence. Proper diagnosis of age-normal or early pathologic conditions. Patient counseling regarding optimum lighting conditions. Patient counseling regarding avoidance of disability glare. Patient counseling regarding upcoming changes in vision. Variable aging rates and the continuum of age-normal to pathology found for many conditions (e.g. cataract & macular degeneration) often make diagnosis rather arbitrary. Clinical experience develops consistency in accurate diagnoses. Adulthood Aging: Clinical Relevance Acknowledging that people age at different rates, expecteds enable… Proper examination methods, including lighting, and sequence. Proper diagnosis of age-normal or early pathologic conditions. Patient counseling regarding optimum lighting conditions. Patient counseling regarding avoidance of disability glare. Patient counseling regarding upcoming changes in vision. Variable aging rates and the continuum of age-normal to pathology found for many conditions (e.g. cataract & macular degeneration) often make diagnosis rather arbitrary. Clinical experience develops consistency in accurate diagnoses. EW8250F07

43 Adulthood Aging: References 1.Atchison, D., & Smith, G. (2000). Optics of the human eye. Butterworth-Heinemann, Oxford. 2.Norton, T., Corliss, D., & Bailey, J., Eds. (2002). The psychophysical measurement of visual function. Butterworth-Heinemann, MA. 3.Schwartz, S. (2004). Visual perception: a clinical orientation. 3rd Ed. McGraw-Hill Companies, Inc., NY. 4.Chalupa, L., & Werner, J., Eds. (2004). The visual neurosciences. MIT Press, MA. 5.Rosenbloom, A., & Morgan, M., Eds. (1993). Vision and aging. 2nd Ed. Butterworth-Heinemann, MA. 6.Gescheider, G. (1997). Psychophysics: The Fundamentals. 3rd Ed. Lawrence Erlbaum Associates, Inc., NJ. 7.Wandell, B. (1995). Foundations of vision. Sinauer Associates, MA. 8.Grosvner, T. (2006). The aging eye: problems that affect acuity and contrast sensitivity. Pacific University College of Optometry, 9.Bruce, V., Green, P., & Georgeson, M. (2003). Visual perception: physiology, psychology and ecology. 4th Ed. Psychology Press, NY. Adulthood Aging: References 1.Atchison, D., & Smith, G. (2000). Optics of the human eye. Butterworth-Heinemann, Oxford. 2.Norton, T., Corliss, D., & Bailey, J., Eds. (2002). The psychophysical measurement of visual function. Butterworth-Heinemann, MA. 3.Schwartz, S. (2004). Visual perception: a clinical orientation. 3rd Ed. McGraw-Hill Companies, Inc., NY. 4.Chalupa, L., & Werner, J., Eds. (2004). The visual neurosciences. MIT Press, MA. 5.Rosenbloom, A., & Morgan, M., Eds. (1993). Vision and aging. 2nd Ed. Butterworth-Heinemann, MA. 6.Gescheider, G. (1997). Psychophysics: The Fundamentals. 3rd Ed. Lawrence Erlbaum Associates, Inc., NJ. 7.Wandell, B. (1995). Foundations of vision. Sinauer Associates, MA. 8.Grosvner, T. (2006). The aging eye: problems that affect acuity and contrast sensitivity. Pacific University College of Optometry, 9.Bruce, V., Green, P., & Georgeson, M. (2003). Visual perception: physiology, psychology and ecology. 4th Ed. Psychology Press, NY. Adulthood Aging sample final exam questions: 2006 Final & NBEO ‘07 Review (EW). EW8250F07


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