How Does Vision Loss Affect Cognitive Function?

There is research that addresses the association between vision impairment and cognitive decline.  The outcome of these studies suggest vision impairment leads to an increased risk of dementia and reduced cognitive function. This may sound bleak, but what if improving vision could lead to better brain health? 

In this post, we’ll explore why vision and cognitive function are closely connected and tips on keeping your vision healthy.

Is There a Link Between Vision Loss and Cognition?

Yes, there is a link between vision loss and cognitive function. Numerous studies have demonstrated a connection between vision impairment and decreased cognitive function.

Studies found a connection between vision impairment and an increased risk of cognitive decline, cognitive impairment, and dementia in older adults (Nagarajan et al., 2022).

Prevalence of Vision Loss and Cognitive Impairment

A systematic review found that 83% of studies examining the vision-cognition relationship reported an association between vision impairment and cognitive impairment (Nagarajan et al., 2022).

Cognitive Domains Affected

Vision impairment is linked to poorer performance in a range of cognitive domains (Varadaraj et al., 2021), including: 

• Language

• Memory

• Attention

• Visual spatial ability

Are Certain Eye Conditions Risk Factors for Dementia?

Certain eye conditions may be potential risk factors for dementia. Vision impairment is associated with an increased risk of cognitive impairment and dementia in older adults (Shang et al., 2021).

Eye conditions that can be associated with increased dementia risk include:

• Age-related macular degeneration (AMD)

• Cataracts

• Diabetes-related eye disease (Solan, 2022)

How Does Vision Loss Affect Cognitive Function?

Vision loss can significantly impact cognitive function in several ways:

1. Spatial awareness and orientation: Individuals with vision loss may struggle to form accurate mental maps of their surroundings. This can make it difficult to navigate daily tasks and everyday life.

2. Information processing: Vision loss can hinder the ability to process and interpret visual information. This can make reading, face recognition, and understanding nonverbal communication more difficult.

3. Cognitive decline risk: Vision impairment has been linked to an increased risk of cognitive decline, cognitive impairment, and dementia.

You May Also Like: Vision and Balance Issues: The Link Between Vision and Balance

Eye Conditions That Links to Cognitive Decline

Several specific eye conditions have been associated with an increased risk of cognitive decline and dementia.

Eye conditions linked to cognitive decline include:

1. Age-related macular degeneration (AMD): Studies have shown that AMD is associated with a 26% increased risk of dementia (Solan, 2022).

2. Cataracts: Research indicates that cataracts are linked to an 11% higher risk of dementia (Solan, 2022). In adjusted models, cataracts were associated with a 38% increased risk of all-cause dementia and a 34% increased risk of Alzheimer's disease (Hwang et al., 2021).

3. Diabetes-related eye disease (DRED): This condition has been associated with a 61% higher risk of dementia (Solan, 2022).

4. Neovascular AMD: One study reported that people with dementia were 37% more likely to have had prior neovascular AMD compared to controls (Xu et al., 2023).

It's important to note that while these eye conditions are associated with an increased risk of cognitive decline, they do not necessarily cause dementia directly.

The relationship between eye health and cognitive function is complex and likely involves multiple factors. Having multiple eye conditions or eye conditions combined with other health issues, such as diabetes or heart disease, may further increase the risk of cognitive decline (Solan, 2022).

Tips to Maintain Vision and Cognitive Health

Maintaining both vision and cognitive health is essential for overall well-being.

Here are some practical tips to help you preserve both:

1. Regular Eye Examinations

Schedule comprehensive dilated eye exams to detect eye conditions early, even before symptoms appear. Early detection is your strongest defense against complications.

2. Seek Care After a Traumatic Brain Injury, Stroke, or Other Neurological Damage

We strongly recommend seeing a neuro-optometrist if you experience a brain injury. At For Eyes, our neuro-optometry exams evaluate eye health and visual acuity following a traumatic brain injury. We can then facilitate a successful neuro-optometric rehabilitation program to ensure the best chance at a full recovery.

3. Healthy Diet

Consume a balanced diet rich in dark leafy greens, fatty fish, and ample fruits and veggies. Leafy greens, such as spinach and kale, are bursting with nutrients that support eye and brain health. Fatty fish, such as salmon and tuna, are high in omega-3 fatty acids. These nutrients support eye health and may reduce the risk of cognitive decline.

4. Regular Physical Activity

Engage in consistent exercise to improve blood circulation, which benefits both the eyes and the brain. Activities like walking can lower the risk of age-related macular degeneration and support cognitive functions.

5. Protect Your Eyes

Wear sunglasses that block 99% to 100% of UVA and UVB radiation to shield your eyes from harmful sun exposure.

6. Manage Chronic Conditions

Keep health issues like high blood pressure, diabetes, and high cholesterol under control, as they can affect both vision and cognitive health.

7. Quit Smoking

Avoid smoking to reduce the risk of eye diseases such as cataracts and age-related macular degeneration. Quitting smoking can also reduce your risk of cognitive decline.

8. Stay Mentally Active

Just as our bodies need exercise to stay healthy, so do our brains. Engage in activities that challenge your brain, like reading, puzzles, or learning new skills. to help maintain cognitive function.

9. Maintain Social Connections

Regular social interactions can support mental health and may reduce the risk of cognitive decline.

10. Protect Against Head Injuries

Use appropriate protective gear during activities to prevent head injuries. Head injuries, such as concussions, can negatively impact both vision and cognitive health.

11. Get Adequate Sleep

A good sleep routine can help support healthy vision. Aim for 7 to 9 hours of quality sleep each night to support brain function and overall health.

By incorporating these habits into your daily routine, you can help maintain both your vision and cognitive health.

The Importance of Regular Eye Exams

Increasing studies show that vision loss or visual impairment and cognition are closely connected. Studies show that vision loss or impairment can negatively impact daily life and lead to cognitive decline.

Cognitive decline due to vision loss can result in decreased independence, reduced social interactions, and difficulty completing daily tasks.

Early detection is an important defense against vision issues, which is why we’ve provided eye tests for over 30 years. Eye tests allow us to perform a comprehensive evaluation of your eye health. We can detect abnormalities, assess vision and overall eye health, and pinpoint potential concerns. 

Book your eye test today to take a proactive approach to keeping your vision and cognitive function healthy. 

Frequently Asked Questions

How does vision loss affect cognition?

When the body loses the ability to properly perceive its surroundings, confusion can ensue. Vision loss can make daily tasks difficult due to balance, proprioception, and visual input issues.

Vision loss can negatively impact a variety of cognitive functions, including:

• Language skills, such as comprehension and word recognition 

• Navigating environments

• Socialising

• Reading

• Memory

• Attention span

How does poor vision affect the brain?

Vision loss can pose a variety of challenges for the brain. The brain relies heavily on visual input for a range of tasks, including everything from balance to social interactions to processing information.

Although the vision-cognition relationship needs further research, it is hypothesised that sensory loss may lead to functional and structural changes in the brain(Vision impairment and cognitive decline among older adults: a systematic review - PMC). 

Vision impairment can negatively impact memory, object recognition, emotional well-being, attention span, social well-being, and language abilities.

Is vision loss a neurological symptom?

Yes, vision loss or visual impairment can be a neurological symptom. Damage to the optic nerve, nervous system, or brain can result in visual loss or impairment. Brain injuries such as stroke, brain tumours, neurological conditions, and concussions can all contribute to visual disorders.

Neuro-optometry aims to treat and manage visual disorders caused by brain injuries by looking at how the eyes and brain work together.

Is vision loss a symptom of dementia?

Vision loss may be an early symptom or a risk factor for dementia. Research indicates a correlation between vision loss and age-related cognitive decline with a higher risk of developing dementia.

Vision loss due to dementia is not a functional issue with the eye. Rather, dementia changes how the brain processes visual information.

Affecting how the brain perceives visual information can lead to difficulties, such as:

• Trouble with spatial awareness

• Issues with depth perception

• Difficulty avoiding obstacles

• Light sensitivity

• Difficulty recognising people

• Trouble with coordination

• Distorted vision

References

Nagarajan, N., Assi, L., Varadaraj, V., Motaghi, M., Sun, Y., Couser, E., Ehrlich, J. R., Whitson, H., & Swenor, B. K. (2022). Vision impairment and cognitive decline among older adults: a systematic review. BMJ Open, 12(1), e047929. https://doi.org/10.1136/bmjopen-2020-047929 

Varadaraj, V., Munoz, B., Deal, J. A., An, Y., Albert, M. S., Resnick, S. M., Ferrucci, L., & Swenor, B. K. (2021). Association of Vision Impairment With Cognitive Decline Across Multiple Domains in Older Adults. JAMA Network Open, 4(7), e2117416. https://doi.org/10.1001/jamanetworkopen.2021.17416 

(2023, June 7). Assessments Prove Link Between Vision Impairment, Cognitive Decline. Reviewofoptometry.com. https://www.reviewofoptometry.com/article/assessments-prove-link-between-vision-impairment-cognitive-decline 

‌Kolli, A., Hood, M. M., Karvonen-Gutierrez, C., Moroi, S. E., Ehrlich, J. R., Gillespie, B. W., Wood, S. D., & Musch, D. C. (2021). Midlife Vision Impairment and Cognitive Function in Later Life: The Study of Women’s Health Across the Nation, Michigan Cohort. The Journals of Gerontology Series A, 76(12), 2178–2186. https://doi.org/10.1093/gerona/glab180 

Solan, M. (2022, January 1). Eye diseases linked to a higher risk of dementia. Harvard Health. https://www.health.harvard.edu/mind-and-mood/eye-diseases-linked-to-a-higher-risk-of-dementia 

‌ Xu, Y., Phu, J., Htein Linn Aung, Negin Hesam-Shariati, Keay, L., Tully, P. J., Booth, A., Anderson, C. S., Anstey, K. J., & Peters, R. (2023). Frequency of coexistent eye diseases and cognitive impairment or dementia: a systematic review and meta-analysis. Eye, 37(15), 3128–3136. https://doi.org/10.1038/s41433-023-02481-4 

‌Hwang, P. H., Longstreth, W. T., Thielke, S. M., Francis, C. E., Carone, M., Kuller, L. H., & Fitzpatrick, A. L. (2021). Ophthalmic conditions associated with dementia risk: The Cardiovascular Health Study. Alzheimer’s & Dementia, 17(9), 1442–1451. https://doi.org/10.1002/alz.12313 

Xu, Y., Phu, J., Htein Linn Aung, Negin Hesam-Shariati, Keay, L., Tully, P. J., Booth, A., Anderson, C. S., Anstey, K. J., & Peters, R. (2023). Frequency of coexistent eye diseases and cognitive impairment or dementia: a systematic review and meta-analysis. Eye, 37(15), 3128–3136. https://doi.org/10.1038/s41433-023-02481-4