Clinical trial NCT03109314: Combining Donepezil With Perceptual Learning in Normal and Amblyopic Human The Effect of Donepezil on Perceptual Learning in Adult Amblyopia
Official title: The Effect of Donepezil on Perceptual Learning in Adult Amblyopia
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE4
Conditions: Amblyopia
Keywords: amblyopia
donepezil
perceptual learning
crowding
contrast sensitivity
visual acuity
Lead sponsor: University of California, Berkeley
Sponsor class: OTHER
First posted: 2017-04-12
Enrollment: 20
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: SEQUENTIAL
Primary purpose: BASIC_SCIENCE

Brief summary: The research deals with amblyopia or lazy eye, a condition that affects about 3% of the population, and results in a variety of visual deficits. Recent work suggests that there is limited neural plasticity in the visual system of adults with amblyopia. This study is aimed at understanding and increasing this plasticity. In this study, the investigators aim to understand how the amblyopic brain learns and how this process is affected by a drug called donepezil, which is sometimes given as a treatment for Alzheimer's disease. The investigators hope that this study will help to identify the chemical components that help the brain to learn, as well as the mechanism of amblyopia. The investigators also plan to test the normal periphery, as control.

Detailed description: The research deals with amblyopia or lazy eye, a condition that affects about 3% of the population, and results in a variety of visual deficits. Recent work suggests that there is limited neural plasticity in the visual system of adults with amblyopia. This study is aimed at understanding and increasing this plasticity. In this study, the investigators aim to understand how the amblyopic brain learns and how this process is affected by a drug called donepezil, which is sometimes given as a treatment for Alzheimer's disease. The investigators hope that this study will help to identify the chemical components that help the brain to learn, as well as the mechanism of amblyopia. The investigators also plan to test the normal periphery, as control.

In this study, donepezil will be administered while amblyopic subjects (or normally sighted subjects tested in the periphery) are trained on a low-contrast single-letter recognition task, or an uncrowd task (recognizing a letter closely embedded within two other letters). Subjects will be asked to identify the target letter (the low-contrast single letter, or the letter embedded within other letters). Training will take place for 10 consecutive days. Pre- and post-tests will be conducted immediately before and after training, and will consist of the measurements of visual acuity, crowding extent and contrast threshold for recognizing single letters.

Eligibility criteria: Subjects with amblyopia

Inclusion Criteria:

* corrected visual acuity being 20/30 or worse in the poorer eye (at least 20/20 in the better eye)
* reduced stereoacuity
* normal retina

Exclusion Criteria:

* with other diagnosed eye diseases

Subjects with normal vision

Inclusion Criteria:

* corrected visual acuity at least 20/20 in each eye
* normal stereoacuity
* normal retina

Exclusion Criteria:

* with other diagnosed eye diseases

Primary outcomes:
measure: Improvement in percent-correct performance in the respective training task
timeFrame: During training (performance will be summarized for each block of trials (a block takes approximately 5 - 10 min to complete). In other words, there should be 100 points of measurements throughout the training period.)
measure: Visual acuity (the smallest letter the participants can see)
timeFrame: Immediately (one day) before and after training
measure: Contrast sensitivity for identifying single letters (the lowest contrast required to identify letters)
timeFrame: Immediately (one day) before and after training
measure: Crowding extent (the extent over which adjacent letters will affect the recognition of a letter)
timeFrame: Immediately (one day) before and after training
Secondary outcomes:
Other outcomes:
Locations:
city: Berkeley
country: United States
facility: University of California, Berkeley
state: California
Study officials:
affiliation: University of California, Berkeley
name: Dennis M Levi, OD, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Chung STL, Li RW, Silver MA, Levi DM. Donepezil Does Not Enhance Perceptual Learning in Adults with Amblyopia: A Pilot Study. Front Neurosci. 2017 Aug 7;11:448. doi: 10.3389/fnins.2017.00448. eCollection 2017.