A high probability of an orientation shift between layers 4 and 5 in central parts of the cat striate cortex

Bauer, Roman

doi:10.1007/bf00237220

Cited by 25 publications

(20 citation statements)

References 25 publications

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“…illustrates the type of data reported by Bauer (1982Bauer ( , 1983. They differ from those described above in that there is a marked dislocation in the region of the IV/V border, such that the orientations recorded in the deeper layers are approximately orthogonal to those which might otherwise have been expected.…”

Section: Resultsmentioning

confidence: 55%

“…Recent reports of a marked and consistent dislocation between orientation columns in the superficial and deep layers of cat striate cortex (Bauer, 1982(Bauer, , 1983 directly contradict the traditional view of the system (Hubel & Wiesel, 1962). This has considerable implications for our current understanding of cortical organization, and in order to clarify the issue we have carried out experiments to test the continuity of the columnar system with depth, in central regions of area 17.…”

Section: Discussionmentioning

confidence: 94%

“…Hence, it may be seen that where some form of discontinuity was observed it was rarely of the type reported by Bauer (1982Bauer ( , 1983; that is to say, a 45-90 deg step-wise shift in orientation preference separating regions with very much lower drift rates. Nevertheless, the distribution of the observed instances is shown in Fig.…”

Section: Continuity Of Orientation Columnsmentioning

confidence: 87%

“…Above it are those occasions when a discontinuity (defined as a sustained shift in orientation preference greater than the inherent variability within the track; that is greater than 30 deg in regions of average base-line scatter) did occur, or when the data could be interpreted in either way. A major fault in the columnar system, ofthe type described by Bauer (1982Bauer ( , 1983, would lead to a large peak in the upper section of the histogram in the division marked by the arrowhead, and a corresponding trough in the lower section. This is clearly not the case.…”

Section: Continuity Of Orientation Columnsmentioning

confidence: 99%

“…Similarly in the cat area 17, it is claimed that a clear discontinuity in the orientation sequence is almost invariably found at the junction between layers IV and Va (Bauer, 1982(Bauer, , 1983. The magnitude of this shift in the cat, although variable, is said to be frequently as high as 90 deg.…”

Section: Introductionmentioning

confidence: 95%

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Continuity of orientation columns between superficial and deep laminae of the cat primary visual cortex.

Murphy¹,

Sillito²

1986

The Journal of Physiology

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SUMMARY1. Recent reports of a marked and consistent dislocation between orientation columns in the superficial and deep layers of cat striate cortex (Bauer, 1982(Bauer, , 1983 directly contradict the traditional view of the system (Hubel & Wiesel, 1962). This has considerable implications for our current understanding of cortical organization, and in order to clarify the issue we have carried out experiments to test the continuity of the columnar system with depth, in central regions of area 17.2. In twenty-four penetrations, eighteen of which were placed as perpendicular as possible to the surface of the cortex, orientation preference was assessed at regular intervals both qualitatively and using a randomly interleaved quantitative technique. The distribution of preferred orientations was analysed with reference to a detailed histological reconstruction of the electrode track, including the location of laminar boundaries and the course of radial tiers of cells and capillaries.3. From a further series of eighteen near-perpendicular penetrations, the change in average orientation between one superficial and one deep layer recording site was compared with the deviation of the track from perpendicular to the surface and hence parallel to the orientation columns.4. In penetrations perpendicular to the surface ofthe cortex, orientation preference showed little variation between superficial and deep laminae. In oblique penetrations, preferred orientation generally changed according to a single, smooth trend. Those irregularities that were encountered were confined to oblique penetrations, and were distributed throughout the cortical laminae.5. In conclusion, our evidence does not support the presence of a systematic discontinuity with depth within the orientation columnar system. It is therefore entirely consistent with earlier evidence on the subject.

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Section: Resultsmentioning

confidence: 55%

Section: Discussionmentioning

confidence: 94%

Section: Continuity Of Orientation Columnsmentioning

confidence: 87%

Section: Continuity Of Orientation Columnsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 95%

See 3 more Smart Citations

Continuity of orientation columns between superficial and deep laminae of the cat primary visual cortex.

Murphy¹,

Sillito²

1986

The Journal of Physiology

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Relationship between preferred orientation and receptive field position of neurons in extrastriate cortex (area 19) in the cat

Leventhal

Schall

Wallace

1984

J of Comparative Neurology

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Orientation sensitivity is a characteristic of most retinal ganglion cells (Levick and Thibos, '82), most relay cells in the dorsal lateral geniculate nucleus (Vidyasagar and Urbas, '82), and most neurons in the visual cortex (Hubel and Wiesel, '62) in the cat. In the retina there is a systematic relationship between receptive field position (polar angle) and preferred orientation. Outside of the area centralis most retinal ganglion cells respond best to stimuli oriented radially, i.e., oriented parallel to the line connecting their receptive fields to the area centralis (Levick and Thibos, '82). This relationship is strongest along the horizontal meridian (the visual streak) and appears to reflect the innate, radial orientation of retinal ganglion cell dendritic fields (Leventhal and Schall, '83). A relationship between preferred orientation and polar angle also exists in cat striate cortex; outside of the area centralis representation most cells respond best to lines oriented radially. This relationship is strongest for S-type cells, the most orientation-selective cells, and cells in regions representing the horizontal meridian (Leventhal, '83). To determine if similar relationships exist in cat extrastriate cortex, the preferred orientations and receptive field positions of 226 neurons in area 19 were studied. We find that, as in area 17, most area 19 cells outside of the representation of the area centralis respond best to lines oriented radially; this relationship is strongest for the cells having the narrowest receptive fields and in regions subserving the horizontal meridian. Unlike in striate cortex, in area 19 the relationship between preferred orientation and polar angle is not dependent upon cell type (S or C) or to the degree of orientation sensitivity exhibited. Also, in area 19, but not in area 17, the relationship between preferred orientation and polar angle fails for the cells having the widest receptive fields.(ABSTRACT TRUNCATED AT 250 WORDS)

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Topographic organization of the orientation column system in large flat‐mounts of the cat visual cortex: A 2‐deoxyglucose study

Löwel

Freeman

Singer

1987

J of Comparative Neurology

121

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We developed a flat-mount technique in order to visualize, without additional reconstruction, the system of orientation columns in the cat visual cortex by using 2-deoxyglucose-autoradiography. Experimental animals were injected with 2-deoxyglucose and then stimulated for 45-60 minutes either with vertical or horizontal or oblique gratings alone or with vertical and horizontal gratings presented in alternation. In both areas 17 and 18 stimulation with either vertical or horizontal or oblique stripes produced similar and highly ordered patterns of parallel bands of increased 2-deoxyglucose uptake that were perpendicular to the boundaries of the areas. In area 17 they occasionally extended without interruption from the 17/18 border on the top of the lateral gyrus to the monocular segment in the splenial sulcus. Superposition of serial sections revealed that these bands were present in all cortical layers and in precise register along lines orthogonal to the lamination. The center-to-center spacing of the bands was 1.0-1.1 mm in area 17 and 1.2-1.4 mm in area 18. Stimulation with alternating vertical and horizontal contours led to a pattern the general organization of which resembled that induced by a single orientation but the spacing of which was reduced by a factor of 0.5. This strongly supports the concept that orientation is mapped in a system of parallel bands and argues against a recently formulated hypothesis that iso-orientation bands extend like spokes from centers that lack orientation selectivity (Braitenberg and Braitenberg, Biol. Cybern. 33:179-186, '79). Another characteristic feature, revealed by the flat-mount technique, was a periodic variation of 2-deoxyglucose uptake along the bands that gave them a beaded appearance. The mean center-to-center distance between adjacent beads on the same band was in the range of 0.9-1.2 mm and remained unchanged when horizontal and vertical gratings were presented in alternation. We propose that these beads reflect another columnar system whose features have yet to be determined.

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A high probability of an orientation shift between layers 4 and 5 in central parts of the cat striate cortex

Cited by 25 publications

References 25 publications

Continuity of orientation columns between superficial and deep laminae of the cat primary visual cortex.

Continuity of orientation columns between superficial and deep laminae of the cat primary visual cortex.

Relationship between preferred orientation and receptive field position of neurons in extrastriate cortex (area 19) in the cat

Topographic organization of the orientation column system in large flat‐mounts of the cat visual cortex: A 2‐deoxyglucose study

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