Study closed out due to recruitment complications.

This study is designed to see if doing regular training on a spatial imagery task leads to improvements in the ability to do the trained spatial imagery task and in the ability to get around in everyday activities.

The investigators will recruit 40 blind participants, randomized by the investigators' CVNR statistician into two groups. One group will undergo the experimental intervention (spatial cognitive training) and the other will undergo a control intervention involving letter-number matching. The participants will include women and minorities in proportion to the demographics of the Veteran population attending the Atlanta VA.

Inclusion Criteria:

• Inability to perceive visual stimuli, i.e. no light perception, with stable visual loss over the past year

• The investigators anticipate that causes of blindness will be ocular, including:

  • glaucoma
  • diabetic retinopathy and macular degeneration
  • the most common causes of blindness in Veterans
  • as well as possibly late-onset Leber's optic atrophy and ocular trauma (in the absence of TBI)

• To minimize heterogeneity due to variations in age and the duration of visual loss, the investigators will restrict enrollment to Veterans and Non-Veterans over the age of 50 who lost light perception within the last 5 years, and who have completed standard O&M training.

• From a practical standpoint, this also enables the investigators to focus on participants who can potentially benefit most from the proposed intervention.

Exclusion Criteria:

• Participants will be excluded if they have any neurological condition, such as:

  • TBI
  • history of blast exposure
  • stroke
  • brain tumors
  • epilepsy, etc.

• Participants will also be excluded if MRI scanning is contra-indicated, e.g.:

  • due to an implanted device such as a pacemaker
  • or foreign bodies of ferromagnetic nature

• Cognitive screening will be performed using the Repeatable Battery for Assessment of Neuropsychological Status (RBANS, Randolph, 1998) and participants with cognitive impairment will be excluded based on a score of 1.5 SD below the mean for the Verbal Memory Index.

• The investigators will test participants' hearing using a validated screening questionnaire (Screening Version of the Hearing Handicap Inventory for the Elderly, HHIE-S, Wentry & Weinstein, 1983, Lichtenstein et al., 1988) followed by assessment of audiometric pure tone (0.5, 1.0, 2.0, 4.0 KHz) hearing thresholds in the CVNR sound booth.

• Participants with more than mild hearing loss (HHIE score >8 or audiometric thresholds >40dB) will be excluded (Wentry & Weinstein, 1983; Wilson, 2009), given that the investigators are relying on audio cues.

• The investigators will also exclude visually impaired Veterans who are dependent on a wheelchair or scooter for mobility, as they will not be able to take part in the real-world task.

Approximately 4 week per participant.