I am new to neuroscience (coming from a data science background), and I'm a little bit confused about the terminology used in many of the resources I have come across. Many studies mention "single-trial" analysis, "single-trial" EEG data and so on and I'm not sure what it means. My guess would be that "single-trial" refers to splitting EEG (or other) data into sub-series and treating each of them as separate trial, where trial means sample. But I don't understand why is it called "single" trial even if we use many of them in final analysis.
Example usage of 'single-trial" I don't understand:
Single-trial analyses refer to methods that consider the variance within subjects. Two broad families of methods can be distinguished: univariate methods extract information among trials in space, time, or both; multivariate methods extract information across space, time, or both, in individual trials. Single-trial analyses may thus be used for behavioral experiments (e.g., Etchells et al., 2011) and neuroimaging experiments (e.g., Cohen and Cavanagh, 2011; Macdonald et al., 2011; Milne, 2011; Rousselet et al., 2011; Touryan et al., 2011; Wutte et al., 2011). Single-trial analyses of neuroimaging data have seen their use increase since the late 1960s, starting with Donchin (1969). Despite this long tradition and several advantages over group analyses, single-trial analyses remain nevertheless marginal.