I have only the vaguest idea who Jonsson was. His obituary in the San Diego Union-Tribune notes only
Sept. 14, 1922-Jan. 24, 2008. He was born in Folk, Sweden, and was an engineer. He served in the Swedish army during World War II. He was a member of the Royal Institute of Navigation and the California Native Plant Society.That is enough to know a little something, however, and he seems entirely familiar with the research over the last 150 years. He makes dozens of fascinating observations - the book is an easy read, BTW - but for our purposes three main ones stand out.
1. We make a cognitive map of a place upon entering it, largely unconscious. (Cognitive map is a term in psychology that does not usually mean "map" in the overhead sense. In this case, it in fact means what we have called landmarks.) If there was an error in this original, it is nearly impossible to erase - and the better a sense of direction one has, the more persistent the wrong map is. The naturally expert wayfinder makes an initial structure for navigation so powerful that it is indestructible. Most frequently, these maps are misoriented by 90 or 180 degrees from the start. Forever after, the navigator cannot convince himself of the true orientation no matter how hard he tries. (The factors which cause this take up much of the book.)
2. Sense of Direction seems to operate most powerfully to the question "Where did this journey start?" People with a good sense of direction can often point back to Start with fair accuracy, even if they have not been paying much attention.
3. People who grow up in urban environments have this intuitive sense of navigation stunted or weakened. So much of the orienting work is done for them that the old, primitive sense of navigation does not develop properly. Additionally, most travel is now done at speeds which exceed our instinctive cognitive map-making abilities. We can still landmark, but it is more attenuated.