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S E Feldon

Publications and source records attributed to S E Feldon.

61 records · Page 4Linked to original sources
PubMed1979

Spatial periodicities of periodic complex cells in the visual cortex cluster at one-half octave intervals.

Within individual penetrations in the visual cortex, spatial periodicities of periodic complex cells differ by either one-half or one octave. When data are pooled from neurons subserving the central visual area in many cats, the results indicate that spatial periodicities cluster at one-half octave intervals over a 2 1/2-octave range (0.95 to 5.4 cyc/deg). Thus a relatively small number of such channels spaced at regular intervals along a logarithmic scale within each orientation column may suffice for this stage of spatial processing.

Animals↗
PubMed1978

Clinical manifestations of brawny scleritis.

We studied four patients with posterior brawny scleritis. Two underwent enucleation for suspected melanoma, and in the other two, the correct diagnosis was made and effective therapy begun. Of seven other eyes with brawny scleritis from other sources, five were enucleated after diagnosis of choroidal melanoma and one for suspected intraocular tumor. This experience and other previous reports indicate the high incidence of diagnostic confusion regarding brawny scleritis. We therefore emphasized clinical symptoms and signs of brawny scleritis: inflammation, tenderness or pain of the globe, history of collagen vascular disease, proptosis, bilaterality, and retinal and choroidal detachment. A preserved normal choroidal vascular pattern over an elevated subretinal mass may be indicative of posterior brawny scleritis. Scleral biopsy is useful for tissue diagnosis. Radioactive phosphorus uptake tests and ultrasonography may erroneously indicate choroidal melanoma and lead to enucleation of a potentially salvageable globe.

Adult↗
PubMed1977

Square-wave jerks: a disorder of microsaccades?

A patient with presenile dementia had instability of ocular fixation caused by small rapid horizontal eye movements (square-wave jerks). High resolution recordings of these eye movements were characteristic of microsaccades, which ordinarily occur during fixation, in all respects except amplitude. In addition, the patient showed complete absence of normal microsaccades. We suggest that microsaccades have become altered in our patient to form a clinical disorder of fixation.

Caloric Tests↗