Landelijke implementatie neonatale gehoorsceening

Addition phenomena in vision and hearing

Studies on the threshold perception - first in the field of vision, later also in the field of hearing - have been a substantial part of the Institute's research programme from the beginning. Since only a few investigators had experience in both fields, an attempt to compare methods and results has never been made. The present author, one of...

Experiment on cochlear summation

A new method for measuring cochlear summation is introduced. This method is an analog of the method earlier applied for measuring retinal summation. The probability of hearing pulses of two small noise bands presented simultaneously is measured as a function ot the frequency difference between these noise bands. Within the experimental error,...

Quantum coincidence requirements during dark-adaptation

Measurements of the geometrical aberrations of the eye

Subjective measurements were made with a telescopic apparatus through small parts of the optical system of the eye. Measures were taken to control the brightness of the object, the state of accommodation and the position of the eye behind the apparatus. The results show that: 1. (1) the focusing system of the eye has an optically inhomogeneous...

Subjective brightness during dark-adaptation

The course of dark-adaptation was studied with threshold measurements and with measures of the luminance required to maintain a constant supraliminal brightness. A stimulus in the light-adapted right eye was matched in brightness to a stimulus presented to the left eye, which was dark-adapted. Two different methods were used and several levels...

The visibility of details of a moving object

Visual contrast thresholds for moving point sources

Over a wide range of brightness of the adapting field, for different color combinations of stimulus and adapting field, contrast thresholds for moving point sources are measured, as a function of the length of the covered track, for different exposure times. When the brightness B of the adapting field does not exceed certain limits, the...

Bijziendheid bij nacht en de aberraties van het oog