Quirky Minds: Terra Incognita

Quirky Minds: Terra Incognita
When half the map is missing—and you don't notice.

After surviving a series of strokes, Kate Lautzenhiser suspected that she had vision problems. At the hospital, she collided with door frames and people on her left side. When she returned home and tried to solve a crossword puzzle, something was off. "I could see the clues," she recalls, "but not the grid printed to the left."
Lautzenhiser suffers from spatial neglect, a neurological condition that results most commonly from stroke. Damage to one brain hemisphere erases awareness of the opposite side of the world. In extreme cases, people with left-neglect see only the digits 12 through 6 on a clock, shave just the right sides of their faces, and eat food from only the right sides of their dinner plates. They may even deny ownership of limbs and try to push "alien" legs out of bed.
Although spatial neglect usually interferes with vision, it can also create deficits in hearing, smell, and the awareness and control of one's body. Maria Mangano-Erichsen copes with both visual and motor neglect. Although she can move her left arm, she never thinks to use it. "I can walk around for an hour with something in my left hand and not realize it," she says. She only chews food using the right side of her mouth, and spontaneous facial expressions are confined to the right half of her face.
Treatment aims to redirect the patient's attention to the neglected side. Some sufferers wear prism glasses that pull their vision in the appropriate direction and can thus rewire the brain. Others see improvements by repeatedly scanning the environment from side to side. Scanning works best in contexts where people practice it, such as reading books, but otherwise the need to scan doesn't always occur to people, says Ian Robertson, an authority on the condition and a professor at Dublin's Trinity College. In the case of motor neglect, patients can issue oral commands to their limbs to help restore their brains' attention to them: "Move, arm!" Ice water in the ear canal can also activate the opposite brain hemisphere and briefly relieve symptoms.
Recovery times vary greatly, but those who can overcome neglect typically do so within the month following a stroke. Mangano-Erichsen has been living with her condition for three years and, despite realizing gains with her prism glasses, still bumps into people and walls, and fears that she will swerve into oncoming traffic when driving. "I don't know if I'll ever get better," she says. ——William Lee Adams
Case Study: Kate Lautzenhiser, Madison, Wisconsin
The injury: Three strokes damaged her brain's right parietal lobe.
The symptoms: She ignores her left visual field and forgets she has a left leg. She is unaware of her leg position unless she looks at it.
Danger: She has burned her left arm several times on oven racks and BBQ flames without feeling it.
Therapy: She plays online mahjong and constantly scans her environment from left to right.
Movement: She must see her feet in order to walk, so she carries groceries and other objects in a wheeled cart. During a water-aerobics class, she must look at her left leg and say, "Left leg, move!"