Experimental conditions are the subsets of an experiment that define the relevant experimental manipulation.
In the Cognitive Atlas, we define a contrast as any function over experimental conditions. The simplest contrast is the indicator value for a specific condition; more complex contrasts include linear or nonlinear functions of the indicator across different experimental conditions.
An indicator is a specific quantitative or qualitative variable that is recorded for analysis. These may include behavioral variables (such as response time, accuracy, or other measures of performance) or physiological variables (including genetics, psychophysiology, or brain imaging data).
Logan GD, Cowan WB, Davis KA
(J Exp Psychol Hum Percept Perform)
Citation added by RPoldrack about eight years ago
Verbruggen F, Logan GD
Neuroscience and biobehavioral reviews (Neurosci Biobehav Rev)
Citation added by RPoldrack about five years ago
Xue G, Aron AR, Poldrack RA
Cerebral cortex (New York, N.Y. : 1991) (Cereb Cortex)
Citation added by NPicchetti about four years ago