Can the Different Cerebral Hemispheres
Have Distinct Personalities?
Evidence and Its Implications
for Theory and Treatment
of PTSD and Other Disorders

Fredric Schiffer, MD

ABSTRACT. The author presents an evidence-based psychological
theory which is derived from clinical observations, a review of the
literature, especially the split-brain literature, and experimentation with
lateral visual field stimulation which has been found to induce changes
in patients’ cognitive and emotional status thought to be associated with
the relative activation of one cerebral hemisphere or the other. The
evidence from lateral visual field stimulation suggests that often each
hemisphere can have distinct psychological perspectives differing especially
in their level of neuroticism with one visual field evoking a more
immature perspective than the other. One of the central tenets of the
hypothesis is that psychological traumas are associated more with one
cerebral hemisphere and than the other, and that the ultimate aim of
psychiatric care then becomes the teaching of the mental entity associated
with this troubled hemisphere that it is now safer and more valued
than it had been at the time of the trauma.

Interpretations of the patient’s difficulties usually evolved from an attempt to empathetically appreciate
how the patient may have felt during a past traumatic period, and that perspective often led to a clearer dynamic
understanding of the patient’s symptoms. Serious psychological theoreticians
did not support the idea that the unconscious resembled an
intact, though troubled, inner child (Munroe, 1955). The popular concept
of the “inner child” did not emerge until the mid-198Os, and was
never fully developed into a sophisticated, complex hypothesis.

During a brief psychiatric interview, one of the two split-brain
patients told me that he had been bullied as a child. He told me further
that he was not at all bothered by those incidents because they had
occurred about 30 years earlier. When he was tested, I asked 3.5 questions
of a general psychological nature such as “How anxious do you feel?”
or “How confident do you feel?” I also asked 14 questions
about the bullies such as “How angry do you feel about the bullies?”
or “How much does the bullying still bother you?” On the general
questions, both hands generally responded similarly, but on the questions
about the bullying there was a large discrepancy between the
responses given by his two hands. His right hand, answering for his
left hemisphere, as he had already told me, indicated that he was not
bothered by the bullies. But his left hand consistently indicated that he
was still very disturbed by the bullying. We interpreted this to mean
that his right brain was still quite upset by the bullying even though his
left was not.

CLINICAL IMPLICATIONS

There are two aspects to the ideas I am presenting and both have
clinical relevance. The first is the general psychological theory that
most people have a mature and an immature part to their personalities.
This hypothesis has usefulness in our attempts to understand human
behavior and to assist people with their psychological problems. This
conceptualization of the mind allows the theoretical insights described
in the previous section. It formulates psychopathology as usually coming
from an immature aspect which still believes it is in the midst of a
traumatic experience. Psychotherapy is then conceptualized as the
teaching of this troubled, immature aspect, that it is in fact safer and
more valued than it has realized. Usually the troubled part of the
personality does not realized that a new, more mature, more realistic
part of the mind has come into existence since childhood. The therapist
can help the patient find and use this more mature part of the
patient’s personality to help the troubled part.

Some of clinicians have reported to me that they feel uncomfortable
trying new techniques and have requested that I present a hands-on
workshop to assist them. I am of the opinion that these techniques are
not so complex and are simply an extension of traditional dynamic
psychotherapy.