The Denny-Brown Collection: useful resource for physical therapy practitioners and educators.

Understanding the effects of central nervous system (CNS) lesions on human motor behavior, and the potential for and stages of recovery, is of paramount importance to physical therapists. We suggest in this review that the Denny-Brown collection has much to offer physical therapists in furthering their understanding of these issues.[2]

The Denny-Brown Collection

Dr Derek E Denny-Brown, at the time of his death in 1981, was the James Jackson Putnam Professor of Neurology Emeritus at Harvard Medical School (Cambridge, Mass). His illustrious career has been described by Gilman,[1] Foley,[2] Geschwind,[3] and Gilliat,[4] and his well-known legacy to neurology includes his classic books, articles, and edited volumes and the many residents, fellows, and students he trained.

Denny-Brown left behind another legacy that is less well known. Between 1948 and 1972, he conducted CNS lesion experiments on about 450 monkeys and made films of the animals postoperatively. The result of this effort is 67,000 m (220,000 ft) of film depicting monkeys with lesions in virtually every major CNS structure. The postoperative behavior of most of the animals was recorded on multiple films that show the animals at various times after both single and successive lesions. Thus, the films often document the recovery process and, by depicting successive lesions, suggest which areas of the brain were instrumental in this process. Typically, the films show each animal sitting, standing, and walking in a cage during examination with a variety of stimuli to evoke standard reflexes (eg, pacing, hopping, righting, tilting, grasping, and avoiding) and responding to passive manipulation of the limbs and noxious stimuli (eg, pinpricks) (Figure). In addition to the films of each animal, there are extensive written records describing the postoperative behavior of the animals, drawings and descriptions of the lesions, photographs of the brain or spinal cord at autopsy, and microscope slides documenting the extent of the lesions.

[Vilensky JA, Gilman S. The Denny-Brown collection: useful resource for physical therapy practitioners and educators. Phys Ther. 1996;76:890-893.]

Key Words: Avoiding, Brain damage, Grasping, Reflexes. In addition to the primate lesion material, the collection includes about 17,000 m (50,000 ft) of film of some of the patients under Denny-Brown's care between 1942 and 1967 in the Neurological Unit of Boston City Hospital and the Neurology Service of Long Island Hospital (a chronic disease hospital maintained by the city of Boston). Many of the films depict patients in various stages of movement disorders such as Wilson's disease, Huntington's disease, and Parkinson's disease, including diseases not currently seen (eg, postencephalitic Parkinson's disease). The depiction of patients with end-stage disease is particularly valuable because currently patients in the terminal stages of such diseases spend their final months in nursing homes or chronic disease facilities; thus, health care professionals often do not have a chance to observe them.

A complete description of the contents of the collection and a detailed description of one of the monkey cases have been published.[5,6] Although we have previously emphasized the research and teaching potential of this collection to scientists and neurologists,[5] we believe that Denny-Brown's approach to his experimental animals and patients makes the collection uniquely valuable to physical therapists.

Denny-Brown's Approach to Examination and Rehabilitation

Two of Denny-Brown's mentors were especially influential in shaping his views on the nervous system and his method of examination of both animals and patients. Sir Charles Sherrington stressed to him the importance of reflexes for understanding the normal functioning of the motor system, and Dr Gordon-Holmes taught him to study the behavior of his patients with the same rigor used to study the behavior of experimental animals. This training led Denny-Brown to examine his animals and patients not from the contemporary viewpoint of identifying the deficit, but from the viewpoint of determining which behaviors (reflexes) are "released." He believed that these released behaviors (ie "positive signs") indicated nervous system disintegration.

To illustrate Denny-Brown's views on the clinical effects of CNS damage, we will use the example of grasping and avoiding responses. Denny-Brown asserted that the primate motor system is anatomically and physiologically arranged to support two opposing strategies relative to the surrounding environment: (1) an exploratory strategy exemplified by grasping and (2) a withdrawal strategy exemplified by avoiding.

In the normally functioning nervous system, the CNS regions that direct these strategies are coordinated and balanced. Injury to the frontal lobe upsets the balance, resulting in the enhancement ("release") of various types of reflex grasping phenomena such as the traction response, grasp reflex, and instinctive grasp reaction, depending on the extent of the lesion and the stage of recovery.[7,8] Sometimes, specific stimuli are required to elicit the grasping behavior (eg, a grasp reflex requires a moving stimulus in the palm), although manifestations of the response are often apparent without such a stimulus (eg, continuous manipulation of objects). The types of grasp phenomena are dependent on differing levels of cerebral organization (eg, subcortical versus cortical), with the more basic responses (eg, a grasp reflex) providing the substrate for recovery of the higher responses (eg, an instinctive grasp reaction in which the hand responds to a tactile stimulus anywhere on it). In studies to test these conceptions, Denny-Brown found that lesions of the cingulate gyrus (area 24), and, to a lesser extent, areas 6 and 8, release grasping responses in monkeys.[8]

Avoiding responses occur in patients with injury to the parietal lobe. When these patients extend a hand outward contralateral to the affected hemisphere, gradual hyperextension of the fingers and wrist occurs. In some patients, stroking the palm results in an exaggeration of the posture, so that the whole arm is raised ("levitation").[8,9] Denny-Brown reported similar responses in monkeys with unilateral ablation of the somatosensory association area of the parietal lobe (area 7), and in monkeys with more extensive parietal lobe ablations.[10] Monkeys with bilateral lesions showed extremely active responses in which the hand avoided contact with the stimulus and the animals reacted violently to being touched. The films of avoiding responses after bilateral lesions are particularly striking, giving the impression that the monkey's hand is repelled by the stimulus as it continually moves to avoid contact. Recent studies[11-16] have substantiated the existence of various forms of grasping following frontal lesions and avoiding following parietal lesions.

Conclusion

We believe that viewing, understanding, and incorporating Denny-Brown's approach to patient examination and rehabilitation may offer physical therapists insights into their patients' behaviors and perhaps suggest novel ways to encourage their recovery. Using funds provided by the National Institutes of Health, we have organized and cataloged the Denny-Brown collection. All of the monkey images are being transferred to videotape. The human films have been evaluated relative to their uniqueness and teaching applications, with the most interesting films currently being compiled into two 1-hour verbally annotated videotapes, one for students (eg, students in undergraduate medical, nursing, or physical therapy programs) and one for professionals (eg, neurologists, physical therapists). Further information regarding the videotapes or the Denny-Brown collection is available from the first author (JAV).

[Figure ILLUSTRATION OMITTED]

References

[1] Gilman S. D Denny-Brown, 1901-1981. Neurology. 1982;32:1-8.

[2] Foley JM. Derek Ernest Denny-Brown, 1901-1981. Ann Neurol. 1982; 11:413-419.

[3] Geschwind N. Derek Ernest Denny-Brown, 1901-1981. J Neurol Sci. 1982;53:137-139.

[4] Gilliat RW. Dr Derek Denny-Brown, OBE, MD, DPHIL, FRCP, 1901-1981: an appreciation. Can J Neurol Sci. 1981;8:271-273.

[5] Vilensky JA, Gilman S, Dec EM. The Denny-Brown collection: a research and teaching resource. Ann NeuroL 1994;36:247-251.

[6] Vilensky JA, Gilman S, Morecraft RJ. DC60: an example of one of the 450 cases that compose the Denny-Brown collection of primate lesion material. Mov Disord. 1996;11:207-213.

[7] Seyffarth H, Denny-Brown DE. The grasp reflex and the instinctive grasp reaction. Brain. 1948;71:109-183.

[8] Denny-Brown DE. Positive and negative aspects of cerebral cortical functions. N C Med J. 1956;17:295-303.

[9] Denny-Brown DE, Meyer JS, Horenstein S. The significance of perceptual rivalry resulting from parietal lesion. Brain. 1952;75:433-471.

[10] Denny-Brown DE, Chambers RA. The parietal lobe and behavior. Res Publ Assoc Res Nerv Ment Dis. 1958;36:35-117.

[11] De Renzi E, Barbieri C. The incidence of the grasp reflex following hemispheric lesion and its relation to frontal damage. Brain. 1992;115:293-313.

[12] Mori E, Yamadori A. Unilateral hemispheric injury and ipsilateral instinctive grasp reaction. Arch NeuroL 1985;42:485-488.

[13] Mori E, Yamadori A. Rejection behaviour: a human homologue of the abnormal behavior of Denny-Brown and Chamber's monkeys with bilateral parietal ablation. J Neurol Neurosurg Psychiatry. 1989;52:1260-1266.

[14] Freund H-J. Abnormalities of motor behavior after cortical lesions in humans. In: Plum F, ed. Handbook of Physiology: The Nervous System, V. Baltimore, Md: Williams & Wilkins; 1987:763-810.

[15] Jeannerod M, Michel F, Prablanc C. The control of hand movement in a case of hemianaesthesia following a parietal lesion. Brain. 1984; 107:899-920.

[16] Pause M, Kunesch E, Binkofski F, Freund H-J. Sensorimotor disturbances in patients with lesions of the parietal cortex. Brain. 1989;1 12:1599-1625.

JA Vilensky, PhD, is Professor of Anatomy, Indiana University School of Medicine, 2101 Coliseum Blvd E, Fort Wayne, IN 46805 (USA) ([e-mail]). Address all correspondence to Dr Vilensky.

Sid Gilman, MD, is Chairman and Professor of Neurology, University of Michigan School of Medicine, Taubman Center 1914/0316, 1500 E Medical Center Dr, Ann Arbor, M1 48109.

This work was supported by the National Institute of Neurological Disorders and Stroke (PHS NS33782).