Despite overall physiological bilateral symmetry, many species exhibit

lateralized biases, i.e., preferences for right- or left-oriented behavior. When

approaching prey, for example, some predator species favor their right eye; some

prey species respond more quickly when their left eye detects a predator. Similar

behavioral asymmetries occur in humans. Most notable is right- and lefthandedness; less notable is the tendency to turn right when entering a room.

Paul Farnsworth found that more successful students tended to choose seats near

the front, a little to the right. He argued that external factors such as teacher

location might have affected this lateral bias. But it is now known that processing

differences between the two brain hemispheres can also contribute to behavioral

asymmetries.

George Karev found that when presented with a movie theater seating

diagram, right-handed people were more likely than left-handed people to choose

a seat on the right, facing front. But he hypothesized that, since the right

hemisphere processes visuospatial and emotional information, the people who

chose right-side seats did so because that would put the screen in their left visual

field, optimizing information flow to the right hemisphere.

Although the right hemisphere is thought to be dominant in processing

emotion, some evidence suggests that the left hemisphere plays a role. The

valence model proposes that the left and right hemispheres process positive and

negative emotion respectively, while the approach-withdrawal model posits that

the left hemisphere processes emotion expressed in approach behavior and the

right hemisphere processes emotion expressed in withdrawal behavior.

Victoria Harms and colleagues suggested that since a paper seating plan was

used in the theater-seating studies by Karev and others, the exhibited preference

might be due simply to handedness: people choose the same side of the paper as

their favored hand. Consequently, the Harms research was designed to study

choices in an actual movie theater. Also, hoping to distinguish between various

explanations, they studied seating choices for comedies (presumed to contain

Positive emotional content), dramas (presumed to contain negative emotional

content), and documentaries (presumed to have balanced emotional content).

They found significant—though not universal—preference for seats on the right,

facing front, regardless of movie genre and of handedness.