Authors:

HAUK, O. & PULVERMÜLLER, F.

Reference:

Year of publication:

2001

CBU number:

5174

Abstract:

This study investigates the influence of word length and word frequency on the human evoked brain potential in a lexical decision paradigm. A factor word length with two levels and a factor word frequency with three levels were introduced: Word stimuli were divided into mono- and bisyllabic items, and those were in turn subdivided into low-, medium-, and high-frequency words. Between-length categories stimuli were matched with respect to word-form frequency and lemma frequency. Between-frequency categories stimuli were matched with respect to the number of letters. The earliest effects of word length were detected around 100 ms, bisyllabic items evoking a larger P1 compared with monosyllabic ones. In contrast to a recent MEG study on a single subject applying a memory task (Assadollahi & Pulvermuller, 2001, Neuroreport, 12, 201-13), frequency effects could be detected only for the comparatively late time windows 320-370 ms and 420-520 ms. In the earlier of these latency ranges, mean amplitude decreases with increasing word frequency, whereas for the later time range the opposite holds true.