Distinct expression of potassium channels regulates visual response properties of lamina neurons in Drosophila melanogaster

The functional organization of the primary visual area (V1) and the importance of sensory experience in its normal development have been well documented in eutherian mammals. However, very few studies have investigated the response properties of V1 neurons in another large class of mammals, or whether sensory experience plays a role in shaping their response properties. Thus we reared opossums ( Monodelphis domestica) in normal and vertically striped cages until they reached adulthood. They were then anesthetized using urethane, and electrophysiological techniques were used to examine neuronal responses to different orientations, spatial and temporal frequencies, and contrast levels. For normal opossums, we observed responses to the temporal and spatial characteristics of the stimulus to be similar to those described in small, nocturnal, eutherian mammals such as rats and mice; neurons in V1 responded maximally to stimuli at 0.09 cycles per degree and 2.12 cycles per second. Unlike other eutherians, but similar to other marsupials investigated, only 40% of the neurons were orientation selective. In stripe-reared animals, neurons were significantly more likely to respond to vertical stimuli at a wider range of spatial frequencies, and were more sensitive to gratings at lower contrast values compared with normal animals. These results are the first to demonstrate experience-dependent plasticity in the visual system of a marsupial species. Thus the ability of cortical neurons to alter their properties based on the dynamics of the visual environment predates the emergence of eutherian mammals and was likely present in our earliest mammalian ancestors.NEW & NOTEWORTHY These results are the first description of visual response properties of the most commonly studied marsupial model organism, the short-tailed opossum ( Monodelphis domestica). Further, these results are the first to demonstrate experience-dependent plasticity in the visual system of a marsupial species. Thus the ability of cortical neurons to alter their properties based on the dynamics of the visual environment predates the emergence of eutherian mammals and was likely present in our earliest mammalian ancestors.

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THE GENETICS OF TYPE A POTASSIUM CHANNELS IN DROSOPHILA MELANOGASTER

Neurotransmitter Release the Neuromuscular Junction ◽

10.1016/b978-0-12-176460-9.50020-3 ◽

1990 ◽

pp. 147-152

Author(s):

A. Mallart.

Keyword(s):

Drosophila Melanogaster ◽

Potassium Channels ◽

Type A

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Visual response properties of neurons in four extrastriate visual areas of the owl monkey (Aotus trivirgatus): a quantitative comparison of medial, dorsomedial, dorsolateral, and middle temporal areas

Journal of Neurophysiology ◽

10.1152/jn.1981.45.3.397 ◽

1981 ◽

Vol 45 (3) ◽

pp. 397-416 ◽

Cited By ~ 170

Author(s):

J. F. Baker ◽

S. E. Petersen ◽

W. T. Newsome ◽

J. M. Allman

Keyword(s):

Receptive Fields ◽

Field Size ◽

Visual Response ◽

Response Properties ◽

Middle Temporal ◽

Optimal Direction ◽

Visual Areas ◽

Direction Of Movement ◽

Owl Monkeys ◽

The Difference

1. The response properties of 354 single neurons in the medial (M), dorsomedial (DM), dorsolateral (DL), and middle temporal (MT) visual areas were studied quantitatively with bar, spot, and random-dot stimuli in chronically implanted owl monkeys with fixed gaze. 2. A directionality index was computed to compare the responses to stimuli in the optimal direction with the responses to the opposing direction of movement. The greater the difference between opposing directions, the higher the index. MT cells had much higher direction indices to moving bars than cells in DL, DM, and M. 3. A tuning index was computed for each cell to compare the responses to bars moving in the optimal direction, or flashed in the optimal orientation, with the responses in other directions or orientations within +/- 90 degrees. Cells in all four areas were more sharply tuned to the orientation of stationary flashed bars than to moving bars, although a few cells (9/92( were unresponsive in the absence of movement. DM cells tended to be more sharply tuned to moving bars than cells in the other areas. 4. Directionality in DM, DL, and MT was relatively unaffected by the use of single-spot stimuli instead of bars; tuning in all four areas was broader to spots than bars. 5. Moving arrays of randomly spaced spots were more strongly excitatory than bar stimuli for many neurons in MT (16/31 cells). These random-dot stimuli were also effective in M, but evoked no response or weak responses from most cells in DM and DL. 6. The best velocities of movement were usually in the range of 10-100 degrees/s, although a few cells (22/227), primarily in MT (14/69 cells), preferred higher velocities. 7. Receptive fields of neurons in all four areas were much larger than striate receptive fields. Eccentricity was positively correlated with receptive-field size (r = 0.62), but was not correlated with directionality index, tuning index, or best velocity. 8. The results support the hypothesis that there are specializations of function among the cortical visual areas.

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Erratum for Movshon et al., Visual Response Properties of Striate Cortical Neurons Projecting to Area MT in Macaques

Journal of Neuroscience ◽

10.1523/jneurosci.17-16-j0001.1997 ◽

1997 ◽

Vol 17 (16) ◽

pp. np-np

Keyword(s):

Cortical Neurons ◽

Visual Response ◽

Area Mt ◽

Response Properties

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Physiological characterization of a rare subpopulation of doublet-spiking neurons in the ferret lateral geniculate nucleus

Journal of Neurophysiology ◽

10.1152/jn.00191.2020 ◽

2020 ◽

Vol 124 (2) ◽

pp. 432-442

Author(s):

Allison J. Murphy ◽

J. Michael Hasse ◽

Farran Briggs

Keyword(s):

Retinal Ganglion Cells ◽

Ganglion Cells ◽

Visual Response ◽

Retinal Ganglion ◽

Visual Responses ◽

Response Properties ◽

Physiological Characterization ◽

Visual Thalamus ◽

Spike Shape

Interest in visual system homologies across species has recently increased. Across species, retinas contain diverse retinal ganglion cells including cells with unusual visual response properties. It is unclear whether rare retinal ganglion cells in carnivores project to and drive similarly unique visual responses in the visual thalamus. We discovered a rare subpopulation of thalamic neurons defined by unique spike shape and visual response properties, suggesting that nonstandard visual computations are common to many species.

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