Electrophysiological Evidence for Sentence Comprehension - Wings

1.1.1. On-line Methods for Sentence Comprehension Research
There are five major on-line methods (or groups of methods) employed in the research of
sentence comprehension. They are: reaction time, reading time, eye-tracking, event-
related potentials measurements (i.e. electrophysiological methods) and functional
neuroimaging in the narrow sense (basically, functional magnetic resonance imaging,
fMRI). In comparisons to various language tests these methods are much more suitable
for capturing two important features of language: its speed and automatic processing. In
addition, electrophysiological methods, as well as fMRI provide information about brain
activity – its time course and localization, respectively.
Reaction time. It is a widely used method in experimental psychology developed by the
Dutch physiologist F.C. Donders in the 19 th century (Donders, 1868). He distinguished
between three types of reaction times: simple, recognition and choice reaction times and
showed that simple RT is shorter than recognition RT and that recognition RT is shorter
than choice RT. This became known as the subtraction method. The reasoning was
simple: if mental processes take time due to their dependency upon the nerve impulses
that last for a measurable amount of time, then various mental processes require different
amount of time depending on their complexity. If a condition X consists of a process A
that takes t1 time and if a condition Y consists of the process A and a process B and they
both last for t2 (and t2>t1), then process B takes t2-t1 time. This simple logic is today
widely used in fMRI experiments (Raichle, 2001) subtracting images, not times. In
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