Does the abstract thinking have a significant role in the relationship between extraversion and evoked brain potentials?

thinking–EP relationship. The results of abstract thinking-EP relationship are presented here (Table 3) only briefly to enable the easier understanding of the complex personality–EP–intelligence relationship, as they are explained in detail in our earlier study (Tatalović Vorkapić et al., 2008). Contrary to our expectations, only three significant correlations between abstract thinking and EPs were determined. Those students who showed higher abstract thinking level also needed a significantly shorter time for selective attention (N1-latency on O1 and on O2), and had a significantly higher N1-amplitude on one parietal electrode. As we have emphasized earlier (Tatalović Vorkapić et al., 2008), further research into the relationship between EPs and abstract thinking is needed, using more trials, more complex tasks within different oddball paradigms, and more adequate electrophysiological apparatus. Extraversion–EP relationship controlled for abstract thinking: Partial correlation analyses. Finally, trying to answer our main question, it can be seen (Table 2) that abstract thinking played a significant role within the extraversion– EP relationship, especially in the relationship of extraversion and late EP-components. Firstly, analyzing the relationship of N1-component and psychological variables (Table 2), it was determined that significant negative correlations between averages on N1-latency and the first ATT-subtest lowered the negative correlation between extraversion and N1-latency when the ATT1 was singled out or partialized. In another words, a part of the N1 latency-extraversion relationship could be ascribed to abstract thinking. A similar pattern could be observed in the correlation analyses of extraversion-N1-amplitude in the second trial on P4-electrode after partializing for the effect of average results on ATT2, which showed a significant positive correlation with N1amplitude on P4-electrode. Furthermore, this pattern could be observed within the relationship of extraversion with N2-component and SW activity latency. However, before analyzing the extraversion–SW latency relationship when partialized for abstract thinking, an interesting finding must be emphasized. Even though a significant negative correlation was determined between extraversion and N2-latency on P4-electrode (r = -.30, p > .05), implying the shorter time for automatic extraction and determination of stimulus’ properties target detection, including shorter reaction time in extraverts, when analyzing the same relationship partialized for abstract thinking, it ceased to be significant. Even more interesting is that this change in the extraversion-N2 latency relationship could not be ascribed to the direct partializing effect of abstract thinking, as its correlations with N2-latency were rather small. Possible explanations for this effect could be the variability effects, the measurement effect, or could be related to the earlier mentioned effort system (Beauducel et al., 2006; Brocke et al., 1996, 1997). The observed changes Table 3 Correlations of the ATT total and ATT subtests with evoked potentials