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A History of Primate Experimentation at the University of Wisconsin, Madison

The early days: Harlow and 50 years of cruelty.

1930 Harry Harlow joins faculty at UW.

Early 30’s Harlow and Abraham Maslow begin studying primates at Henry Vilas Zoo.

1932 UW gives Harlow space for primate colony.

Colony grows to include monkeys of a variety of species, sometimes caged together. Harlow takes note of monkeys’ apparently calculated behavior, an observation at odds with the then accepted mechanistic theories of animal behavior.

Late 1940s Harlow begins his voluminous production of literature about monkeys.

1949 Meyer DR, Harlow HF. The development of transfer of response to patterning by monkeys.

1950 Harlow HF. Performance of catarrhine monkeys on a series of discrimination reversal problems.

1950 Harlow HF. Learning and satiation of response in intrinsically motivated complex puzzle performance by monkeys.

1950 Harlow HF. The effect of large cortical lesions on learned behavior in monkeys.

1950 Davis RT, Settlage PH, Harlow HF. Performance of normal and brain-operated monkeys on mechanical puzzles with and without food incentive.

1951 Meyer DR, Harlow HF, Ades HW. Retention of delayed responses and proficiency in oddity problems by monkeys with preoccipital ablations.

1951 Harlow HF, Meyer D, Settlage PH. The effects of large cortical lesions on the solution of oddity problems by monkeys.

1952 Harlow HF, Davis RT, Settlage PH, Meyer DR. Analysis of frontal and posterior association syndromes in brain-damaged monkeys.

1952 Meyer DR, Harlow HF. Effects of multiple variables on delayed response performance by monkeys.

1952 Warren JM, Harlow HF. Discrimination learning by normal and brain operated monkeys.

1952 Warren JM, Harlow HF. Learned discrimination performance by monkeys after prolonged postoperative recovery from large cortical lesions.

1952 Harlow HF, Warren JM. Formation and transfer of discrimination learning sets.

1952 Leary RW, Harlow HF, Settlage PH, Greenwood DD. Performance on double-alternation problems by normal and brain-injured monkeys.

1953 Harlow HF. Mice, monkeys, men, and motives.

1953 Harlow HF. Higher functions of the nervous system.

1953 Fay JC, Miller JD, Harlow HF. Incentive size, food deprivation, and food preference.

1954 Harlow HF, McClearn GE. Object discrimination learned by monkeys on the basis of manipulation motives.

1954 Butler RA, Harlow HF. Persistence of visual exploration in monkeys.

1954 McClearn GE, Harlow HF. The effect of spatial contiguity on discrimination learning by rhesus monkeys.

1955 Harlow HF, Schlitz KA, Settlage PH. Effect of cortical implantation of radioactive cobalt on learned behavior of rhesus monkeys.

1955 Blazek NC, Harlow HF. Persistence of performance differences on discriminations of varying difficulty.

1955 Moon LE, Harlow HF. Analysis of oddity learning by rhesus monkeys.

1955 Moon LE, Harlow HF, Bogumill GP. Some effects of periodic x-radiation.

1955 French GM, Harlow HF. Locomotor reaction decrement in normal and brain-damaged Rhesus monkeys.

1956 Harlow HF, Moon LE. The effects of repeated doses of total-body x radiation on motivation and learning in rhesus monkeys.

1956 Schrier AM, Harlow HF. Effect of amount of incentive on discrimination learning by monkeys.

1956 Harlow HF, Schrier AM, Simons DG. Exposure of primates to cosmic radiation above 90,000 feet.

1956 Blazek NC, Harlow HF, McClearn GE. Manipulatory motivation in the infant rhesus monkey.

1956 Blazek NC, Harlow HF, Mason WA. Learning capacities of the infant rhesus monkey.

1957 National Heart Institute (NHI) and National Advisory Heart Council form planning committee to promote a national primate center for cardiovascular research.

1957 Planning committee selects Howard Curtis, Leon Schmidt, Theodore Ruch, and Harlow to prepare a recommendation.

1957 Harlow et al, distribute “A Proposal for a National Primate Institute.”

In order to better understand the nature of biological processes as they occur in man it is necessary to have available for research animals which resemble man as closely as possible. Many diseases processes which occur in man can be studied only in man and subhuman primates. An outstanding example of this is poliomyelititis, and it is well known thatr this disease could not have been brought under control with an abundant supply of moinkeys. Maedical research is becoming more and more precise. Many research fields have gone almost as far as they can using lower animals, and progress lies in applying these methods and ideas to higher animals so that the relationship to man will be better understood. (12-16-1957) [Quoted in The Alpha Males: An early history of the regional primate research centers. Dukelow WR. University Press of America.1995.]

1958 Mason WA, Harlow HF. Formation of conditioned responses in infant monkeys.

1958 Mason WA, Harlow HF. Performance of infant rhesus monkeys on a spatial discrimination problem.

1958 Schrier AM, Harlow HF. Effect of reserpine on avoidance of humans by Rhesus monkeys.

Harlow H. 1958. The nature of love. Address of the President at the sixty-sixth Annual Convention of the American Psychological Association, Washington, D. C., August 31, 1958. First published in American Psychologist, 13, 573-685.

The macaque infant differs from the human infant in that the monkey is more mature at birth and grows more rapidly; but the basic responses relating to affection, including nursing, contact, clinging, and even visual and auditory exploration, exhibit no fundamental differences in the two species. Even the development of perception, fear, frustration, and learning capability follows very similar sequences in rhesus monkeys and human children.

1959 Harlow HF. Love in infant monkeys.

1959 Harlow HF, Zimmerman RR. Affectional responses in the infant monkey; orphaned baby monkeys develop a strong and persistent attachment to inanimate surrogate mothers.

US House and Appropriations Committees agree to appropriate $2 million for establishment of first two national primate colonies. Oregon is chosen as first site; Seattle, Washington, second.

October 1960 Harlow submits application for Wisconsin to become one of the new federally funded primate research colonies.

1960 Harlow HF. Primary affectional patterns in primates.

1961 Harlow’s application is approved; Wisconsin Primate Center is formally funded.

1962 Construction begins.

1962 Harlow HF. The effects of early experiences upon the personal-social, heterosexual, and maternal behavior of rhesus monkeys.

1962 Seay B, Hansen E, Harlow HF. Mother-infant separation in monkeys.

1962 Cadell TE, Harlow HF, Waisman HA. EEG changes in experimental phenylketonuria.

1962 French GM, Harlow HF. Variability of delayed-reaction performance in normal and brain-damaged rhesus monkeys.

1962 Harlow HF, Harlow MK. The effect of rearing conditions on behavior.

1962 Harlow HF, Harlow M. Social deprivation in monkeys.

1964 April 27-28 Wisconsin Regional Primate Center officially dedicated.

Summer 1964 Wisconsin Primate Center fully operational, including holding facility constructed with NIH funds at Henry Vilas Zoo. Harlow is director of his own primate laboratory and the Wisconsin Primate Center. There are now approximately 900 monkeys on hand; 90% are rhesus macaques.

1964 Seay B, Alexander BK, Harlow HF. Maternal behavior of socially deprived rhesus monkeys.

1964 Harlow HF, Rowland GL, Griffen GA. The effect of total social deprivation on the development of monkey behavior.

1965 Seay B, Harlow HF. Maternal separation in the rhesus monkey.

1965 Harlow HF, Dodsworth RO, Harlow MK. Total social isolation in monkeys.

For the past ten years we have studied the effects of partial social isolation by raising monkeys from birth onward in bare wire cages such as those shown in Figure 1. These monkeys suffer total maternal deprivation and, even more important, have no opportunity to form affectional ties with their peers. We have already reported the resulting progressively deepening syndrome of compulsive nonnutritional sucking, repetitive stereotyped movements, detachment from the environment, hostility directed outwardly toward others and inwardly toward the animal’s own body, and inability to form adequate social or heterosexual attachments to others when such opportunities are provided in preadolescence, adolescence, or adulthood.

More recently, we have initiated a series of studies on the effects of total social isolation by housing monkeys from a few hours after birth until 3, 6, or 12 months of age in the stainless-steel chamber illustrated in Figure 2. During the prescribed sentence in this apparatus, the monkey has no contact with any animal, human or subhuman. Although social isolation is total, no attempt is made to maximize sensory deprivation. The chamber is constantly illuminated, transmits sounds, and affords relatively adequate opportunities for cutaneous-proprioceptive expression and exploration. The room outside the living cage was sound-masked by a 70-db white noise source, but loud sounds from the corridor produced attentive and even freezing responses.

1966 Harlow HF, Harlow M. Learning to love.

1966 Griffin GA, Harlow HF. Effects of three months of total social deprivation on social adjustment and learning in the rhesus monkey.

1967 Arling GL, Harlow HF. Effects of social deprivation on maternal behavior of rhesus monkeys.

1967 Harlow wins National Medal of Science.

1968 Harlow seeks treatment at Mayo Clinic for his depression. He receives drugs and electroshock therapy. Treatment partially successful.

1969 Kerr GR, Chamove AS, Harlow HF. Environmental deprivation: its effect on the growth of infant monkeys.

1970 Harlow HF, Suomi SJ. Nature of love--simplified.

1970 Harlow HF, Thompson CI, Blomquist AJ, Schiltz KA. Learning in rhesus monkeys after varying amounts of prefrontal lobe destruction during infancy and adolescence.

1970 Chamove AS, Harlow HF. Exaggeration of self-aggression following alcohol ingestion in rhesus monkeys.

1970 Harlow HF, Schiltz KA, Blomquist AJ, Thompson CI. Effects of combined frontal and temporal lesions on learned behaviors in rhesus monkeys.

1970 Suomi SJ, Harlow HF, Lewis JK. Effect of bilateral frontal lobectomy on social preferences of rhesus monkeys.

1970 Suomi SJ, Harlow HF, Domek CJ. Effect of repetitive infant-infant separation of young monkeys.

1971 McKinney WT Jr, Suomi SJ, Harlow HF. Depression in primates.

1971 Harlow HF, Suomi SJ. Production of depressive behaviors in young monkeys.

1971 Harlow HF, Mc Kinney WT Jr. Nonhuman primates and psychoses.

1971 Suomi SJ, Harlow HF, Kimball SD. Behavioral effects of prolonged partial social isolation in the rhesus monkey.

June 30, 1971 Harlow steps down from directorship of WPRC. He remains director of his own lab and continues his experiments.

Robert Goy replaces Harlow as WPRC director.

1972 McKinney WT Jr, Suomi SJ, Harlow HF. Vertical-chamber confinement of juvenile-age rhesus monkeys. A study in experimental psychopathology.

1972 Suomi SJ, Harlow HF. Depressive behavior in young monkeys subjected to vertical chamber confinement.

1972 McKinney WT Jr, Suomi SJ, Harlow HF. Repetitive peer separations of juvenile-age rhesus monkeys.

1973 Harlow HF, Novak MA. Psychopathological perspectives.

1973 Young LD, Suomi SS, Harlow HF, McKinney WT Jr. Early stress and later response to separation in rhesus monkeys.

1973 Schiltz KA, Thompson CI, Harlow HF, Mohr DJ, Blomquist AJ. Learning in monkeys after combined lesions in frontal and anterior temporal lobes.

1973 Chamove AS, Rosenblum LA, Harlow HF. Monkeys (Macaca mulatta) raised only with peers. A pilot study.

1973 Harlow HF, Plubell PE, Baysinger CM. Induction of psychological death in rhesus monkeys.

1974 Harlow HF, Suomi SJ. Induced depression in monkeys.

1975 Suomi SJ, Harlow HF. Effects of differential removal from group on social development of Rhesus monkeys.

1975 Mears CE, Harlow HF. Play: early and eternal.

1975 Suomi SJ, Eisele CD, Grady SA, Harlow HF. Depressive behavior in adult monkeys following separation from family environment.

1975 Suomi SJ, Collins ML, Harlow HF, Ruppenthal GC. Effects of maternal and peer separations on young monkeys.

1976 Ruppenthal GC, Arling GL, Harlow HF, Sackett GP, Suomi SJ. A 10-year perspective of motherless-mother monkey behavior.

1976 Suomi SJ, Delizio R, Harlow HF. Social rehabilitation of separation-induced depressive disorders in monkeys.

1980 Bowman RE, Heironimus MP, Fobes J, Leary RW, Harlow HF. Facilitation of discrimination learning but not of learning set by post-training injections of pentylenetetrazol in rhesus monkeys.

1981 Harlow dies in Arizona.


Madison's Hidden Monkeys is a joint project of the
Alliance for Animals and the
Primate Freedom Project