yt
amar
ous system comes to us from the cerebral process, which is induced through
sense organs. On the other hand we
receive through the resolving power
re
automated.
As
a result,
the
desired
success is achieved with more speed
and more precision, and mechanisms
of great complexity are mastered.
of receptive systems information about
the environmental source of stimulation. In visual perceptions derived from
both eyes, for example, paralactic shift
is utilized in composing an integrated
stereo image. The impression that the
sensory stimulation originates in the en-
vironment is confirmed through the di-
rected motor reaction—for example,
through the grasping of a visually localized object. The successful attempt to
grasp the object confirms the correlation between perception and reality.
Involved are consistent temporal and
spatial relationships which produce the
impression of causality (29).
Simple mechanisms for the preservation of life are genetically controlled
and subject to phylogenetic selection.
Important individual behavioral patterns are determined prenatally. Complex reactions, on the other hand. are
learned postnataliy, and their release
is under the control of conscious will.
Through frequent repetition, psychic
functions become partially or totally
Summary
This article is based upon data which
are suitable for the correlation of behavioral research and experimental neurophysiclogy. Causal thinking manifests
a sort of integrative activity which
brings simultaneous and successive
patterns of nervous excitation into
a subjectively meaningful frame of reference. While neuronal patterns determine the content of consciousness, they
fail to provide clues concerning the
transformation of such patterns into
subjective experience.
References and Notes
1. C. J. Herrick, The Evolution of Human Nature (Univ. of Texas Press, Austin, 1956).
2. The Neuropsychology of Lashley (selected
papers of K. 5. Lashley), F. A. Beach, D. O.
Hebb, C. T. Morgan, H. W. Nissen, Eds.
(McGraw-Hill, New York, 1960).
3. D. O. Hebb, The Organization of Behavior
(Wiley, New York, 1949).
4, W. Penfield and T. Rasmussen, The Cerebral
Cortex of Man (Macmillan, New York, 1950).
5. H. Kiliver. J. Lancet 72, 567 (1952);
:
in Ciba Foundation Symposium on the Neurological Basis of Behavior, G. E. W. Wolstenhoime and C. M. O’Connor, Eds. (Little,
Brown, Boston, 1958), p. 175.
6. D. W. Ploog, Jahrb, Max-Planck-Ges. (1963),
p. 130; P. D. MacLean, Animal Behaviour
11, 32 (1963).
7, J, M. R. Delgado, Intern, Rev. Neurobiol. 6.
349 (1964).
8. P. D. MacLean, Psychosomart. Med. 11, 338
(1949): A.M.A. Arch. Neurol. Psychiat. 78,
113 (1957).
9. S. L. Polyak, The Vertebrate Visual System
(Univ. of Chicago Press, Chicago, 1957).
10. R. Jung, in The Visual System, R. Jung and
H. Kornhuber, Eds. (Springer, Berlin, 1961),
p. 410.
11. D. H. Hubel and T. N. Wiesel, f. NeuroPhysiol, 28, 229 (1965).
12. G, Baumgartner, in The Visual System, R.
Jung and H. Kornhuber, Eds, (Springer, Berlin, 1961), p. 296.
13. B. J. Alpers, Res. Pub. Ass. Nervous Mental
Diseases 20, 725 (1940).
14. B, Andersson, Acta Physiol. Scand. 28, 188
(1953);
, P. A. Jewell, S. Larsson, Ciba
Foundation Symposium on the Neurological
Basis of Behavior (Little, Brown, Boston,
1958), p. 76: B. K. Anand and J. R. Brobeck,
Yale J. Biol. 24, 123 (1951).
15. W. R. Hess, Diencephaion, Autonomic and
Extrapyramidal Functions, O. Krayer, Trans.
(Grune & Stratton, New York, 1954);
and M. Briigger. Helv, Physiol. Pharmacel.
Acta 1, 33 (1943); R. W. Hunsperger, ibid.
14, 70 (1956).
16. B. Andersson and W. Wyrwicka, Acta Physiol, Scand. 41, 194 (1957).
17. W. R. Hess, The Biology of Mind (Univ. of
Chicago Press, Chicago, 1964).
18. W. A. Stoll, Schweiz. Arch. Neurol. Neurochir, Psychiat. 60, 1 (1947).
19. W. R. Hess, Psychologie in Biologischer Sicht
(Thieme, Stuttgart, ed. 2, 1967).
20. The work discussed was supported by a grant
from the Swiss National Foundation of Scientific Research.
1500 instances of laboratory-acquired
infections resulting in 39 deaths. A
standing Committee on Laboratory Infections and Accidents of the Ameri-
can Public Health Association (APHA
Arbovirus Infections of
Laboratory Workers
/CLIA) (3) has maintained a file of
cases of laboratory-acquired infections
whether reported to the public or by
Extent of problem emphasizes the need
have been over 2700 cases with 107 fatalities.
for more effective measures to reduce. hazards.
R. P. Hanson, S. E. Sulkin, E. L. Buescher, W. McD. Hammon,
private communication; so far, there
Molecular biologists interested in the
relation of viruses to the metabolic
systems of cells and in the structure
of their nucleic acids may now be
added to the many virologists who have
long worked with a heterogeneous
group of viruses known as_ arboviruses. The health hazard inherent in
the manipulation of these viruses may
ruses. The magnitude of the overall not be well known to many of the
problem of laboratory-acquired infecnewer investigators who lack clinically
tions, however, became evident in an exoriented training.
tensive survey (2) which revealed over
The arboviruses, a contraction of
R. W. McKinney, and T. H. Work
Prior to 1950, only an occasional report was concerned with the need for
protection of laboratory personnel who
came in daily contact with disease-producing agents. Sulkin and Pike (/) had
collected data on viral infections contracted in laboratories in the hope that
this information would be helpful in
determining where the greatest caution
must be exercised in working with vi8 DECEMBER 1967
The authors are members of the American Committee on Arthropod-borme Viruses/Subcommittee
on Laboratory Infections (ACAV/SLI). Dr. Hanson is in the department of veterinary science,
University of Wisconsin, Madison; Dr. Sulkin is in the department of microbiology, University of
Texas Southwestern Medical School, Dallas; Dr. Buescher is in the department of virus diseases,
Walter Reed Army Institute of Research, Washington, D.C.; Dr. Hammon is in the department
of epidemiology and microbiology, University of Pittsburgh, Pittsburgh, Pennsylvania; Dr. McKi me) .
is at Ft. Detrick, Frederick, Maryland; Dr, Work is in the department of infectious and thople ?
diseases, University of California School of Public Health, Los Angeles.
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