The left hemisphere governs our ability to express ourselves in language. In over 95% of right-handed people the left hemisphere is dominant for speech. The figure is somewhat lower for left handers, approximately 70%, but still highly significant. The left hemisphere is better then the right at recognizing sequences of words and letters. It controls our logic, our reasoning, and our analytical thought processes. It can focus on details, however it has difficulty comprehending the whole picture.
The perceptual functions of the right hemisphere are more specialized for the analysis of space and geometrical shapes and forms, elements that are all present at the same time (not so sequential like language). The right hemisphere is the creative half, it can "see" the whole out of parts, thus allowing us to connect puzzle parts together. The right hemisphere also plays and important role in the comprehension of emotion. In an experiment where subjects were shown pictures of a faces with strong facial expression, the right hemisphere was able to discern the expression more accurately then the left hemisphere. In addition, an experiment was done where subjects listened to verbal messages said with different emotions. The messages were presented to each ear separately. When presented to the left hemisphere, the subject was more accurate with regards to the verbal content of the message. However the right hemisphere was more accurate at identifying the emotional tone of the voice.
Ehrenwald (1984: 16) has classified important differences between the hemispheres as follows:
|Thinking||Abstract, linear, analytic||Concrete, holistic|
|Cognitive style||Rational, logical||Intuitive, artistic|
|Language||Rich vocabulary, good grammar and syntax; pose||no grammar, syntax; prosody, poor vocabulary metaphoric, verse|
|Executive capacity||Introspection, will, initiative, sense of self, focus on trees||Low sense of self, low initiative, focus on forest|
|Specialized functions||Reading, writing, arithmetic, sensory-motor skills; inhibits psi||Three i's, music, rich dream imagery, good face and gestalt recognition, open to psi|
|Time experience||Sequentially ordered, measured||"Lived" time, primitive time sense|
|Spatial orientation||Relatively poor||Superior, also for shapes, wire figures|
|Psychoanalytic aspects||Secondary process, ego functions, consciousness; superego?||Primary process, dream-work, free assoc. hallucinations?|
|Ideal prototype||Aristotle, Appollonian mode, Marx, Freud, Koestler's Commissar||Plato, Dionysian mode, Nietzsche, Jung Koestler's Yogi|