318 Abnormal Psychology
Neuroscience research overturned view that the cerebral
hemispheres are identical in the latter half of the nineteenth
century. Results of neurological research, including autopsies
performed on patients with psychological deficits related to
brain tumors and traumas, correlation of behavioral changes
with ablation of particular structures of the central nervous
system, direct electrical stimulation of areas of the exposed
brain in living subjects and the corresponding techniques of
measuring degree and locus of electrical activity of the brain
evoked by systematic stimulation of areas of the body, all lent
support for the theory that different psychological functions
are localized in separate areas of the brain.
LATE NINETEENTH INTO TWENTIETH CENTURY
Theory of the Evolution of the Brain
and Psychopathology
J. Hughlings Jackson (1835–1911), an English neurologist
who specialized in neuropathology, confirmed Broca’s dis-
covery of the speech center, finding in most cases that aphasia
in right-handed persons is associated with disease of the left
cerebral hemisphere. In 1863, he observed epileptic convul-
sions that progress through the body in a series of spasms;
such convulsions are now known as “Jacksonian epilepsy.”
He theorized that the lower functional levels of the human
mind are dynamically and unconsciously present in all
healthy individuals and are temporarily released from control
of the higher cortical centers whenever the cortex is relatively
inactive, as during sleep, and in cases of cortical damage.
Jackson concluded that the behavioral symptoms of brain
damage are determined by the functioning of one or more
lower centers that have been freed from the inhibitory control
normally imposed on them by the higher brain centers. He
pointed out that this evolutionary sequence can be observed in
individual mental development and suggested that in old
age, in various neurological diseases, and in most forms of in-
sanity there occurs a general reversal of this developmental/
evolutionary process (Jackson, 1887).
The Clinico-Anatomic Method
The discovery of cerebral localization of motor, sensory, and
even integrative psychological functions supported the thesis
that psychological functions are localized in the brain. If
particular psychological functions are localized in different
parts of the brain, it follows that various manifestations of
psychopathology might be caused by diseases of specific
parts of the brain. In this view, the domain of psychopathol-
ogy represents various specific diseases to be described in
order to establish descriptive categories. The diseases can
then be related to specific underlying diagnosable neurologi-
cal pathologies. This is conceptually a “pathogen model” of
psychopathology. This view was largely hereditarian but not
necessarily so, as organically based psychopathology could
be caused by innate or acquired brain dysfunctions.General ParesisBy the late nineteenth century large numbers of mentally ill
persons were crowded in the large public institutions, some
suffering from alcoholism, others from old age and dementia,
and still others were probably “natural fools.” Still others suf-
fered from various metabolic and neurological diseases and
brain damage. Many suffered from general paresis (originally
called “general paralysis of the insane” or GPI). Autopsy of
the brains revealed widespread brain tissue destruction, but
no one knew that general paresis had a specific pathology
linked to syphilis until Krafft-Ebing established that this
form of insanity is the tertiary stage of syphilis, a delayed,
but not inevitable, result of a syphilitic infection. In 1897,
he inoculated with the syphilis spirochete nine individuals
with general paresis and no known history of syphilitic infec-
tion. None developed secondary symptoms. Researchers
concluded that they must have been previously infected,
although they had not developed the usual symptoms of
syphilis. This finding established that an early infection
with syphilis is the cause of general paresis. The symptoms,
which begin to appear 15 to 20 years after the initial infec-
tion, include manic-like behavior, with euphoria, delusions
of grandeur and persecution and depression, and disorders of
speech and locomotion, similar to those found in some major
psychiatric disorders. The hypothesis of syphilitic infection
was not fully accepted until Noguchi and Moore produced
definitive proof by finding evidence of the spirochete in the
brains of syphilitics (Moore, 1910).Brain Lesions and PsychopathologyThroughout the second half of the nineteenth century, many
physicians attributed all mental derangement to cerebral
pathology. Technical limitations mostly prevented physicians
from establishing the nature and location of central nervous
system pathology until after the patient had died, and so med-
ical researchers turned to autopsies to confirm the supposi-
tion that brain pathology underlay psychopathology.
D. Hack Tuke (1881), in his presidential address to the
Medico-Psychological Association, reviewed autopsy re-
search into the physical correlates of mental pathology. He