Age-Related Macular Degeneration: the Effect of Training on Visual Performance and Neural Activity

Kristina Visscher, Ph.D.

University of Alabama School of Medicine

Funded in December, 2010: $200000 for 3 years
LAY SUMMARY . BIOGRAPHY .

LAY SUMMARY

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Determining how vision can be improved in patients with macular degeneration

Investigators will determine how macular degeneration modifies visual activity in the brain, and how this activity is further modified by training designed to increase the speed of patients’ cognitive processing.  

About two million older adults have an advanced stage of macular degeneration. The disorder causes them to lose the ability to see in the center of their visual field, including parts of the eye’s retina called the “macula.” Ordinarily, this area is responsible for our visual ability to read, recognize faces and scrutinize objects and scenes. The visual information is passed on to the brain’s primary visual cortex, where it is processed. While macular degeneration destroys this key visual field, patients retain vision in the outer part of the retina. Many patients are able to compensate by using these spared visual areas, while others are not. The reasons for this disparity are not clear. Prior research in patients, however, indicates that a specific area of the brain’s primary visual cortex, called the “lesion projection zone,” remains active even though it receives no information from the retina. Activity in this zone may account for the ability by many patients with macular degeneration to compensate for their visual loss. The investigators, therefore, will use fMRI imaging to explore how macular degeneration modifies neural activity in the lesion projection zone, and how this neural activity is further modified by cognitive training.

They hypothesize that: (1) patients undergo remapping of their visual cortex, which represents development of alternative ways to focus attention; (2) standardized training designed to speed the pace of patients’ cognitive processing further modifies these neural changes; and (3) the extent to which patients improve their performance on visual tasks will correlate with the extent of the changes in the visual cortex that improve attention and also produce stronger connections with the brain’s motor cortex. Using fMRI imaging in 24 adults with macular degeneration and 24 healthy volunteers, they will first determine whether patients’ visual cortex has undergone visual remapping. Then, 12 of the patients will participate in a standardized cognitive training regimen designed to increase the speed at which they process cognitive information. All 24 patients will then be re-imaged, and investigators will determine whether the trained patients perform better on visual tasks compared to the untrained patients, and whether their improved performance is correlated with further changes in function in their visual cortex.

Significance: The research could lead to methods to tailor cognitive training to the needs of each individual patient with age-related macular degeneration to maximize residual visual skills.  

INVESTIGATOR BIOGRAPHIES

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Kristina Visscher, Ph.D.

BIOGRAPHICAL SKETCH

Provide the following information for the Senior/key personnel and other significant contributors in the order listed on Form Page 2.
Follow this format for each person.  DO NOT EXCEED FOUR PAGES.

 

NAME

Fletcher, Donald C.

POSITION TITLE

Scientist (Affiliate) – Smith-Kettlewell

Associate Professor – Univ. of Kansas

eRA COMMONS USER NAME (credential, e.g., agency login)

FLORIDAFLETCH

EDUCATION/TRAINING  (Begin with baccalaureate or other initial professional education, such as nursing, include postdoctoral training and residency training if applicable.)

INSTITUTION AND LOCATION

DEGREE

(if applicable)

MM/YY

FIELD OF STUDY

University of Alberta, Edmonton, Canada

B.Sc.

1978

Medical Science

University of Alberta, Edmonton, Canada

M.D.

1982

Medicine

 

 

 

 

 

 

 

 

 

 

 

 


 

A.   A. Personal Statement

The goal of this project is to test how ongoing activity in visual cortex of macular degeneration patients differs from patients with healthy vision.  In addition, we propose to examine how training with a speed of processing paradigm impacts both behavior and fMRI activity in the AMD patients.  My expertise studying age-related macular degeneration and specifically the impacts of training on outcomes of patients with AMD will be helpful for designing the studies and for interpreting the results.

 

B. Positions and Honors.

Professional Experience

1982-1985                               Ophthalmology Residency: University of Saskatchewan, Saskatoon, Canada.

1985-1986                               Retina Fellowship: Presbyterian Medical Center, Denver, CO.

1986-1987                               Low Vision Rehabilitation Fellowship: Pacific Medical Center, San Francisco, CA.

1992-1995                               Assistant Professor: University of Missouri, Kansas City; Ophthalmology.

1992-1995                               Adjunct Associate Professor: University of Kansas; Allied Health, Occupational Therapy.

1995-2001                               Clinical Associate Professor: University of South Florida, Tampa; Ophthalmology.

1996-pres.                               Adjunct Clinical Associate Scientist: Schepens Eye Research Institute, Boston.

2000-2004                               Associate Professor: University of Alabama, Birmingham; Ophthalmology.

2004-present               Scientist (Affiliate): The Smith-Kettlewell Eye Research Institute, San Francisco.

2004-present               Full time faculty: California Pacific Medical Center, San Francisco; Ophthalmology.

2009-present               Adjunct Associate Professor: University of Kansas, Dept. of Ophthalmology, Kansas City

 

Honors

Recipient: Honor Award and Senior Achievement Award, American Academy of Ophthalmology (AAO).

Recipient: Meritorious Award for Outstanding Lifetime Contributions to Low Vision, Association for Education and Rehabilitation of the Blind and Visually Impaired (AER).

Past-member: Ophthalmic Practice Committee, AAO.

Past-chair: Low Vision Rehabilitation Committee, AAO.

Past-member: NEI’s Visual Impairment & Rehabilitation Panel.

Member: Editorial Board, Retinal Physician, 2005 to present.

Member: Professional Issues Committee, (AER), 2006 to present.

AAO representative: American Congress of Rehabilitation Medicine.

Advisor: National Eye Health Education Program.

Member: Scientific Advisory Board, Helen Keller Eye Research Foundation.

Board of Directors: Oakland Lions Blind Center

Participant: volunteer medical work in Africa, South America and Asia.

Memberships

American Academy of Ophthalmology (AAO)

American Congress of Rehabilitation Medicine (ACRM)

American Medical Association (AMA)

Association for Education and Rehabilitation of the Blind and Visually Impaired (AER)

Association for Research in Vision and Ophthalmology (ARVO)

 

C. Selected Peer-Reviewed Publications.

Publications

Fletcher DC, Schuchard RA.  Preferred Retinal Loci (PRLs) relationship to macular scotomas in a low vision population. Ophthalmology 1997; 104(4): 632-8.

Massof RW, Rubin GS, Tielsch JM, Fletcher DC.  Estimation of vision disability scales from item responses on visual function questionnaires. Optical Society America 1999; February.

Fletcher DC, Schuchard RA, Watson G.  Relative locations of macular scotomas near the PRL:  Effect on low vision reading. Journal of Rehabilitation Research and Development 1999; 36(4): 356-64.

Massof RW, Fletcher DC.  Evaluation of the NEI Visual Functioning Questionnaire as an interval measure of visual ability in low vision. Vision Research 2001; 41(3): 397-413.

Morris RE, Fletcher DC, Scott SS.  Counseling and rehabilitation. Ophthalmology Clinics of North America 2002, 15(2): 167-70.

Fletcher DC, Dreer L, Elliott T.  A tactile analogue scale instrument for investigation of low vision patient psychological characteristics. Proc. London Vision Conference, International Congress Series 2005.

Fletcher DC, Schuchard RA.  Visual function in patients with CNV due to AMD: The importance of looking beyond visual acuity. Optometry and Vision Science 2006; 83(3): 178-89.

Fletcher DC.  Acuity does not equal vision. Retinal Physician, March/April Supp. 2006; 3-6.

Renninger LW, Verghese P, Fletcher DC.  Efficienct eye movements for low vision rehabiltiation. Journal of Vision 2007; 7(15): 98a. http://journalofvision.org/7/15/98/

Renninger LW, Dang L, Verghese P, Fletcher DC.  Effect of central scotoma on eye movement behavior. Journal of Vision 2008; 8(6): 641a. http://journalofvision.org/8/6/641/

Fletcher DC, Schuchard RA, Walker JP, Raskauskas PA.  Patient with Macular Disease, good visual acuity, and central visual field disruption and significant difficulties with activities of daily living. Journal of Visual Impairment and Blindness 2008; 102(10): 656-8.

Markowitz S, Kent C, Schuchard R, Fletcher DC.  Ability to read medication labels improved by participation in a low vision rehabilitation program. Journal of Visual Impairment and Blindness 2008; 102(12): 774-7.

Schoessow KA, Fletcher DC.  Shifting Desktop Video Magnfier Monitors to Compensate for Central Scotomas. AER Journal Research and Practice in Visual Impairment and Blindness 2009; 2(2): 76-83.

Fletcher DC, Renninger LW.  Acuity Alone Does Not Indicate the Extent of Macular Disease.  Retinal Physician 2009; 6(3): 64-6.

 

 

 

 

 

 

 

 

D. Research Support.

Ongoing Research Support

Fletcher (PI)                                                                                  01/01/10 – 12/31/10

The Smith-Kettlewell Eye Research Institute

“Research on Devices, Technologies and Assessment Tools”

The goal of this project is to develop and evaluate new rehabilitation technology and methods for the blind and visually impaired.

Role: PI

 

2 R01 EY018004-04 Renninger (PI)                                            04/01/10 – 03/31/13

NIH/NEI

“CRCNS: Where to Look Next? Modeling Eye Movements in Normal and Impaired Vision”

The goal of this proposal is to develop an explanatory and predictive model of eye movement planning in normal and low vision that can be used to objectively design and measure the effectiveness of low vision rehabilitation.

Role: Co-PI

 

4 R44 EY018781-02 Hallinan (PI)                                                04/01/08 – 03/31/11

NIH/NEI

“Sight on Call: Remote Services for the Blind and Low Vision”

The goal of this proposal is to develop a cell phone based service of on-call sighted assistants to the estimated 3.4 million blind and low-vision Americans.

Role: Scientist

 

Kuykendall (PI)                                                                             07/01/08 – 06/30/10

NSF

“3D Lithography of Thick Photopolymers for Imaging and Photonic Crystal Waveguides”

The goal of the project is to develop a lightweight, headmounted image delivery and capture system. The system will have the ability to image the retina and deliver gaze-contingent stimuli. Low vision applications include use as a visual aid and as an “all-in-one” vision testing and rehabilitation training system.

Role: Scientist

 

Completed Research Support

Renninger (PI)                                                                              01/01/09 – 12/31/09

Pacific Vision Foundation

“Binocular Field Testing”

The goal of this project is to develop, evaluate and validate three new tools for binocular field mapping. Special emphasize is placed on the evaluation of PC-based software tools that are inexpensive and accessible to the low vision rehabilitation community.

Role: Co-Investigator

 

5 R44 EY014487-04 Nitzberg (PI)                                                09/01/07 – 08/31/09

NIH/NEI

“A Smart Telescope for Low Vision”

The goal of this project is to develop a device for persons with low vision that uses computer vision algorithms to search for, detect and enhance targets such as text and faces to aid in everyday tasks such as travel, navigation, and social interactions.  It will consist of a miniature camera and visual display discreetly mounted on spectacles or a hat, and a compact computing device and set of controls that fit into a pocket.  The commercial version is meant for persons with acuity between approximately 20/60 and 20/500.

Role: Scientist