|
Toward a Psychocivilized Society
Jose M. R. Delgado, M.D. © 1969
(Electrical Stimulation of the Brain)
On the basis of many studies during cerebral surgery,
Penfield has said of anger, joy, pleasure, and sexual excitement in the human brain
that "so far as our experience goes, neither localized epileptic discharge nor
electrical stimulation is capable of awaking any such emotion. One is tempted to
believe that there are no specific cortical mechanisms associated with these emotions."
This statement still holds true for the cerebral cortex, but studies in human subjects
with implanted electrodes have demonstrated that electrical stimulation of the depth
of the brain can induce pleasurable manifestations, as evidenced by the spontaneous
verbal reports of patients, their facial expression and general behavior, and their
desire to repeat the experience. In a group of twenty-three patients suffering from
schizophrenia, electrical stimulation of the septal region, located deep in the frontal
lobes, produced an enhancement of alertness sometimes accompanied by an increase in
verbal output, euphoria, or pleasure. In a more systematic study in another group of
patients, further evidence was presented of the rewarding effects of septal stimulation.
One man suffering from narclolepsia was provided with a small stimulator and a built-in
counter which recorded the number of times that he voluntarily stimulated each of several
selected points in his brain during a period of seventeen weeks. The highest score was
recorded from one point in the septal region, and the patient that pushing this particular
button made him feel "good" as if he were building up to a sexual orgasm, although he was
not able to reach the end point and often felt impatient and anxious. His narcolepsia
was greatly relieved by pressing this "septal button." Another patient, with psychomotor
epilepsy also enjoyed septal self-stimulation, which again had the highest rate of button
pressing and often induced sexual thoughts. Activation of the septal region by direct
injection of acetylcholine produced local electrical changes in two epileptic patients
and a shift in mood from disphoria to contentment and euphoria, usually with concomitant
sexual motivation and some "orgastic sensations."
These results indicate the need for careful functional exploration during brain surgery
in order to avoid excessive euphoria or depression when positive or negative reinforcing
areas are damaged. Emotional instability, in which the subject bursts suddenly into tears
or laughter without apparent reason, has been observed following some neurosurgical
interventions. These major behavior problems might have been avoided by sparing the
region involved in emotional regulation.
In our own experience, pleasurable sensations were observed in three patients with
psychomotor epilepsy. The first case was V.P., a 36-year-old female with a long history
of epileptic attacks which could not be controlled by medication. Electrodes were
implanted in her right temporal lobe and upon stimulation of a contact located in
the superior part about thirty millimeters below the surface, the patient reported
a pleasant tingling sensation in the left side of her body "from my face down to the
bottom of my legs." She started giggling and making funny comments, stating that she
enjoyed the sensation "very much." Repetition of these stimulations made the patient
more communicative and flirtatious, and she ended by openly expressing her desire to
marry the therapist. Stimulation of other cerebral points failed to modify her mood
and indicated the specificity of the evoked effect. During control interviews before
and after ESB, her behavior was quite proper, without familiarity or excessive
friendliness.
The second patient was J.M., an attractive, cooperative, and intelligent 30-year-old
female who had suffered for eleven years from psychomotor and grand mal attacks which
resisted medical therapy. Electrodes were implanted in her right temporal lobe, and
stimulation of one of the points in the amygdala induced a pleasant sensation of
relaxation and considerably increased her verbal output, which took on a more intimate
character. This patient openly expressed her fondness for the therapist (who was new
to her), kissed his hands, and talked about her immense gratitude for what was being
done for her. A similar increase in verbal and emotional expression was repeated when
the same point was stimulated on a different day, but it did not appear when other
areas of the brain were explored. During the control situations the patient was rather
reserved and poised.
The third case was A.F., an 11-year-old boy with severe psychomotor epilepsy. Six days
after electrode implantation in both temporal lobes, his fourth tape-recorded interview
was carried out while electrical activity of the brain was continuously recorded and
5-second stimulations were applied in a prearranged sequence at intervals of about
four minutes. The interviewer maintained an air of friendly interest throughout,
usually without intiating conversation. After six other excitations, point LP located
on the surface of the left temporal lobe was stimulated for the first time, and there was
an open and precipitous declaration of pleasure. The patient had been silent for the
previous five-minute interval, but immediately after this stimulation he exclaimed,
"Hey! You can keep me here longer when you give me these; I like those." He went on
to insist that the ongoing brain tests made him feel good. Similar statements with
an emphatic expression of "feeling good" followed eight of a total sixteen stimulations
of this point during the ninety-minute interview. Several of these manifestations were
accompanied by a statement of fondness for the male interviewer, and the last one was
accompanied by a voluptuous stretch. None of these manifestations appeared during
the twenty-two minutes when other points were excited. Statistical analysis of the
difference between the frequency of pleasurable expressions before and after onset
of stimulations proved that results were highly significant (P<0.001).
The open expressions of pleasure in this interview and the general passivity of behavior
could be linked, more or less intuitively, to feminine strivings. It was therefore
remarkable that in the next interview, performed in a similar manner, the patient's
expressions of confusion about his own sexual identity again appeared following
stimulation of point LP. He suddenly began to discuss the desire to get married, but
when asked, "To whom?" he did not immediately reply. Following stimulation of
another point and a one-minute, twenty-second silence, thepatient said, "I was
thinking - there's - I was saying this to you. How to spell 'yes' - y-e-s
. I mean y-o-s. No! 'You' ain't y-e-o . It's this. Y-o-u." The topic was then
completely dropped. The monitor who was listening from the next room interpreted
this as a thinly veiled wish to marry the interviewer, and it was decided to
stimulate the same site again after the prearranged schedulehad been completed.
During the following forty minutes, seven other points were stimulated, and the
patient spoke about several topics of a completely different and unrelated content.
Then LP was stimulated again, and the patient started making references to the
facial hair of the interviewer and continued by mentioning pubic hair and his
having been the object of genital sex play in the past. He then expressed doubt
about his sexual identity, saying, "I was thinkin' if I was a boy or a girl --
which one I'd like to be." Following another excitation he remarked with evident
pleasure: "You're doin' it now," and then he said, "I'd like to be a girl."
|