This disorder means people will experience difficulty in finding their way in familiar surroundings.
Topographic disorientation (TD) can be very disabling yet may go undetected. This inability to navigate through the environment usually involves the person being unable to learn routes in new environments as well.
TD is generally viewed as an impairment in spatial memory and has been given different names such as visual disorientation, topographic amnesia and spatial disorientation.
Making our way around our house or driving across the city is a complex behaviour involving many components. TD varies from person to person depending on the area of the brain affected. For example one area of the brain acquires spatial information, another develops long-term representation of position while another will perceive relevant landmarks on a journey.
A person may not even remember how to get around their home any more. Another may remember strategic landmarks but not be able to compute their positional relationship to each other. Others may remember well established routes but be unable to learn a new one. The degree people are affected by TD depends on whether they can develop strategies that will compensate for the disorder.
Some people can still make their way around town by using maps and constantly asking for directions. Some may benefit from the GPS satellite navigation units that can now be fitted to cars which will give verbal instructions to reach destinations.
Small portable units are also available and becoming cheaper each year.
Condensed from the Topographic Disorientation fact sheet at Synapse.org.au
This story was first seen in the Synapse bridge magazine www.synapse.org.au