Sensory hind-limb representation in the Sml cortex of the cat after spinal tractotomies

Levitt, M.; Levitt, Janice

doi:10.1016/0014-4886(68)90057-5

Cited by 53 publications

(5 citation statements)

References 64 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The cats in this study retained or recovered somatosensory discriminative function in spite of profoundly disturbed electrophysiology of hindlimb somatosensory cortex. Cortical responses of the cats in the present experiment were unaffected acutely by the lesion, confirming an evoked potential study on kittens by Andersson and Leissner (1972) and 3 acutely prepared cats reported by Levitt and Levitt (1968b). However, 10 days or more after the lesion was placed, recordings from the hindleg area of somatosensory cortex I were markedly altered.…”

Section: Discussionsupporting

confidence: 89%

Somatosensory function and cortical unit activity in cats with only dorsal column fibers

1977

View full text Add to dashboard Cite

Cats received lesions that transected the entire thoracic cord except for partial sparing of the dorsal columns. The cats were required to discriminate the side on which they were touched, the size of simultaneously presented discs, or the direction their fur was stroked to obtain food reward. All cats found by anatomical and/or electrophysiological criteria to have any functional continuity in the dorsal columns were able to master the first of these tasks; some responded above chance on the second. Performance was at chance on blank trials, and cats with complete cord transection failed to discriminate. Lesioned cats did not orient or otherwise react to any nonrewarded stimulus below the level of the lesion. A total of 532 units were recorded under light barbiturate anesthesia from the hind paw projection near the tip of the ansate sulcus in these and other similarly prepared cats. Three-fourths of the units found before and acutely after the cord lesions were made were driven by hind limb stimulation. Only 27% of the units recorded 10 or more days afterwards could be driven. Of these driven units, 15 (38%) responded to foreleg stimulation, 13 exclusively so. No such units were found in intact or acutely lesioned cats.

show abstract

Section: Discussionsupporting

confidence: 89%

Somatosensory function and cortical unit activity in cats with only dorsal column fibers

1977

View full text Add to dashboard Cite

show abstract

“…A further problem has been noted by Levitt & Levitt (63). Complete destruction of the dorsal columns is likely to damage fibers in the dorso lateral fasciculus which certainly contains important afferent pathways.…”

Section: Section Of Dorsal Columnsmentioning

confidence: 95%

“…N udeus ventralis posterior lateralis (VPL) in thalamus receives many inputs other than from the dorsal column nucleus: these include afferents from lateral cervical nucleus, (50), the spinothalamic tract (71,72), the reticular formation (8, 95), midbrain tegmentum (82), the opposite VPL (2), cortex (56), and the inferior colliculus (55). A number of studies have been made of the physiological properties of cells in thalamus or cortex following destruction of either dorsal columns or dorsal column nuclei or the lemniscal decussation (2, 10, 60,63,84,89,105,115). All agree that there is a considerable loss of cells with small receptive fields, low thresholds, and high specificity, but it is still debated whether any are left when the lateral cervical nucleus projections are intact.…”

Section: Section Of Dorsal Columnsmentioning

confidence: 99%

Somatosensory Pathways

Wall¹,

Dubner²

1972

Annu. Rev. Physiol.

View full text Add to dashboard Cite

All reviews are selective: here, we have chosen to concentrate on some of the recent points of interest in somatosensory afferent systems. The reader is warned that one of the authors is naturaIly biased in favor of his own survey on the dorsal columns (111). However a more traditional and com prehensive review on this subject is available (85). GENERAL SCHEMES FOR AFFERENT SYSTEMSEach succeeding A nnual Review tends to define the nervous system in terms of more and more specific subdivisions. The intention of this progres sion is to identify and study the ultimate and indivisible particles whose reconstitution forms the entire system. This search for elementary particles is the most respectable of scientific analytic tactics; final success nevertheless depends on selecting the correct elemental categories. The history of science shows many examples of considerable progress in analysis based on categories which eventually became non-productive. Generations of men at least as clever as we are developed an elaborate technology and, in that sense, an understanding of materials based on the categories of earth, air, fire, and water. Generations of neurophysiologists have also developed categories, each based on a model of the way the system is assumed to operate; the justification and usefulness of these categories, stated or implicit in previous work, are now being questioned.What are these categories in which the organization and function of afferent systems are described? First, there are the categories of origin, as implied in the names of the cutaneous, proprioceptive, and visceral afferent systems. Within these there are subdivisions which may depend either on morphologically recognizable end organs such as muscle spindles, Golgi tendon organs, and Pacinian corpuscles, or on physiologically recognizable axons such as nociceptors, heat detectors, and cold detectors. No one now doubts the existence of these structures and functions as described, although there remain the questions whether all the morphological types are funda mentally different from each other-especially, whether the physiological 315 1082 Annu. Rev. Physiol. 1972.34:315-336. Downloaded from www.annualreviews.org Access provided by Lancaster University -UK on 02/05/15. For personal use only.Quick links to online content Further ANNUAL REVIEWS

show abstract

“…Cells in these three distinct, albeit primary receiving areas are responsive to touch, texture, shape, motion, and the direction of stimulus movement, including temporalsequential patterning, and can directly monitor the position and movement of the ex-tremities (Levitt & Levitt, 1968;Mountcastle, 1957;Warren, Hamalainen, & Gardner, 1986a,b;Whitsel, Roppolo, & Werner, 1972). In this manner, we can detect an insect crawling up or down our leg and the direction in which it is moving, as well as determine the position of our arms and legs without looking at them.…”

Section: The Primary Somesthetic Receiving Areasmentioning

confidence: 99%

“…Because most of these neurons receive input concerning pressure, light touch, the movement of joints, and muscular activity (Levitt & Levitt, 1968;Mountcastle, 1957), they can signal and determine whatever posture or position the body is in as well as the amount of force or pressure being exerted by the limbs (Jennings, Lamour, Solis, & Fromm, 1983), i.e., if carrying or lifting some object.…”

Section: The Primary Somesthetic Receiving Areasmentioning

confidence: 99%

Neuropsychology, Neuropsychiatry, and Behavioral Neurology

Joseph¹

1990

Critical Issues in Neuropsychology

View full text Add to dashboard Cite

PrefaceThis book is written for the clinician, students, and practitioners of neuropsychology, neuropsychiatry, and behavioral neurology. It has been my intent throughout to present a synthesis of ideas and research findings. I have reviewed thousands of articles and research reports and have drawn extensively from diverse sources in philosophy, psychology, neurology, neurosurgery, neuropsychiatry, physiology, and neuroanatomy in order to produce this text. Of course I have also drawn from my own experience as a clinician and research scientist in preparing this work and in this regard some of my own biases and interests are represented.

show abstract

Sensory hind-limb representation in the Sml cortex of the cat after spinal tractotomies

Cited by 53 publications

References 64 publications

Somatosensory function and cortical unit activity in cats with only dorsal column fibers

Somatosensory function and cortical unit activity in cats with only dorsal column fibers

Somatosensory Pathways

Neuropsychology, Neuropsychiatry, and Behavioral Neurology

Contact Info

Product

Resources

About