A quantitative investigation of spine and dendrite development of neurons in visual cortex (area 17) ofMacaca nemestrina monkeys
- 1 August 1979
- journal article
- research article
- Published by Wiley in Journal of Comparative Neurology
- Vol. 186 (3), 473-489
- https://doi.org/10.1002/cne.901860310
Abstract
In a previous Golgi study (Lund et al., '77) which examined the development of the macaque monkey striate cortex (area 17) it was observed that the dendrites of neurons within the visual cortex show a marked increase in the number of spines on their surface during the first eight weeks of postnatal life. The qualitative observation was also made that all neurons then showed a marked decrease in spine numbers by the time the animal was adult. Since these spines are known to be sites of synaptic contact, changes in their numbers may reflect changes in synapse populations on these neurons. This study examines quantitatively spine frequency and total dendritic development of Golgi impregnated neurons in monkeys ranging in age from 145 days gestation to adult. Four cell types were studied: spiny stellate neurons from laminae IVCα and IVCβ and pyramidal neurons with soma in either lamina IIIB or upper lamina VI. After consideration of possible sources of variation in spine numbers several conclusions are made: (1) Dendritic spine development appears to be a tightly controlled process both in terms of actual numbers of spines on a neuron at any one age and in the rate of change of spine frequency. (2) The neurons populations examined all show a gradual increase in spine numbers up to eight weeks of age. (3) At least two different trends are found in spine population maturation after the eight week point: (A)‐the spine population may remain constant at the eight week level for same period of time or (B)‐there may be a rapid decline in spine numbers following the eight week peak. (4) There is a suggestion that those neurons associated with direct input, or early stages in the relays, from the parvocellular geniculate laminae show trend B, while those associated with magnocellular input, or later order combined relays within the cortex, show trend A. (5) Different parts of a single pyramidal neuron dendrite may show either trend A or trend B, depending on the lamina location of the dendritic segment considered. (6) All neurons show spine population decreases between nine months of age and adult (5–7 years) suggesting continuing long term maturational changes.This publication has 34 references indexed in Scilit:
- Functional Plasticity in the Immature Striate Cortex of the Monkey Shown by the [ 14 C]Deoxyglucose MethodScience, 1978
- Polyneuronal innervation of skeletal muscle in new‐born rats and its elimination during maturation.The Journal of Physiology, 1976
- Abolition of Direction Selectivity in the Visual Cortex of the CatScience, 1976
- Visual cortical cells: their developmental properties in normal and dark reared kittens.The Journal of Physiology, 1976
- Innate and environmental factors in the development of the kitten's visual cortex.The Journal of Physiology, 1975
- The development of synapses in the visual system of the catJournal of Comparative Neurology, 1975
- Physiological consequences of unilateral and bilateral eye closure in macaque monkeys: some further observationsBrain Research, 1975
- Synaptic patterns on different cell types in the different laminae of the cat visual cortex. An electron microscope studyBrain Research, 1968
- Changes in Visual Cortex on First Exposure of Rats to Light: Effect on Synaptic DimensionsNature, 1967
- The representation of the visual field on the cerebral cortex in monkeysThe Journal of Physiology, 1961