studies investigating fertility decline in developing countries often adopt measures of determinants of fertility behavior developed based on observations from developed countries, without adapting them to the realities of the study setting. as a result, their findings are usually invalid, anomalous or statistically non-significant. this commentary draws on the research article by moeeni and co...

Perceived contrast is reduced after prolonged exposure to a textured pattern (contrast adaptation). The size of this effect is dependent on the relationship between the adapting contrast and the test contrast. It is generally accepted that the greatest reductions occur when the adapting contrast is much higher than the test contrast. Here this relationship was examined for a wide range of spati...

Previous studies have shown that adapting to a complex grating may produce little rise in the contrast threshold of a test grating whose spatial frequency matches one of the higher harmonics of the adapting pattern. The present study shows that adaptation may be strong if the adapting component of a complex grating appears visible as a separate grating. The adapting component could be made to a...