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ELECTROPHYSIOLOCICAL THEORY
47
al.,
1957)
localizes the projections
in
sensorimotor, frontal oculomotor,
paraoccipital
or
posterior-parietal, orbito-frontal, and anterior cingulate
cortex,
together with superior, anterior,
and
medial-basal portions of
the temporal lobes, with an absence of corticoreticdar projections from
other regions of cortex. Various suggestions have been made for the in-
fluenceof these projections
on
central activity: they may affect arousal
and
states
of arousal, both behavioral and electrical; facilitate
or
in-
hibit motor activities (Sloan and Kaada)
;
modulate and suppress sen-
sory input, control states of alertness and somnolence, and affect the rate
of nerve conduction (French et al.). French and his associates noted the
striking
resemblance
in
cortical topography between these areas and
the so-called suppressor areas, which are now thought to be regulatory
rather than inhibitory in function.
Jasper and his associates
(1952)
reported
a
rich projection from para-
striate cortex to the intralaminar thalamus, with an absence
of
corre-
sponding projections from striate cortex. This indication of a projection
from
a
secondary
sensory area (visual
11)
is borne out by the general
cortical topography of these projections, which reads well as a sche-
matum
of
secondary levels of registration and discrimination for all
sensory modalities, together with the oculomotor, orbitofrontal, tem-
poral, and anterior cingulate regions. The reasons for regarding these
latter regions of the cortex
as
also belonging
on
a
second level of cortical
activity are presented in a later section of this paper.
The implication
is
strong that these projections carry cortically dis-
criminated information of sensory
origin
into
the central integrating
system and therefore into immediate consciousness.
The inhibition
or
attenuation
of
these projections should of itself have the behavioral
effect of separating cortically defined
senswy
information from immedi-
ate, active, waking cm-ess ,
and hence produce general hypnosis.
Hypnosis intervenes, possibly
in
this manner, between the level of
sensory-afferent perception and the level
of
higher integration and re-
spome, to maintain
a
blockage which in full hypnosis empties conscious
mental experience
of
effective sensory content.
Amnesia, automatism, and apathy.
A
coherent theory
of
hypnosis
mu& account
for
the dramatic symptoms
of
amnesia, automatism, and
apathy.
To
put the case conversely, hypnosis appears to involve a dis-
turbance of the processes and mechanisms by which serial memories,
intents,
and affects are elaborated
in
the brain. The experimental evi-
dence suggeststhat
these
dysfunctions
in
hypnosis may most reasonably
be connectedwith the exclusion from central response of data projected
from anterior-temporal, orbitofrontal,
and
anterior cingulate cortex re-
sDectivelv.
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