Hassan Auwal Bello, Begum Tahamina, Reza Mohammed Faruque, Yusoff Nasir
Department of Neurosciences, School of Medical Science, Universiti Sains Malaysia, Health Campus, 16150 Kubang Kerian, Kelantan, Malaysia.
Malays J Med Sci. 2016 Nov;23(6):70-82. doi: 10.21315/mjms2016.23.6.8. Epub 2016 Dec 7.
Previous studies have revealed that self-related tasks (items) receive more attention than non-self-related, and that they elicit event-related potential (ERP) components with larger amplitudes. Since personality has been reported as one of the biological correlates influencing these components, as well as our behavioural differences, it is important to examine how it affects our self-consciousness in relation to tasks of varied relevance and the neurological basis.
A total of 33 male and female undergraduate Malaysian medical students of Universiti Sains Malaysia (USM) participated in the study. The participants were divided into two groups, Ambivert ( = 18) and Extravert ( = 15) groups, using the USM personality inventory questionnaire. In the ERP experiment, squares containing standard stimuli of any word other than self and non-self-related nouns (e.g., , , , etc.; in English: Ball, Teeth, Kids, etc., respectively), those containing self-related pronouns (, or ; in English: I, Us or We, respectively), and non-self-related pronouns (, or ; in English: He/She, You or They, respectively), were shown 58%, 21% and 21% of the time, respectively, in a three-stimulus visual oddball paradigm. All words were presented in Bahasa Melayu. The participants were instructed to press 1 for self and 2 for non-self, and ignore standard stimuli.
Comparison of both N200 and P300 amplitudes for self-related and non-self-related pronouns in the Extravert group revealed significant differences at seven electrode sites, with self-related having larger amplitude at anterior electrodes and less at posterior. This was not seen in the Ambivert group.
The present study suggests that self-relevant pronouns are psychologically more important to extraverts than to ambiverts; hence, they have more self-awareness. This may be due to large amount of dopamine in the brains of extraverts, which is more concentrated in the frontal lobe.
先前的研究表明，与自我相关的任务（项目）比非自我相关的任务受到更多关注，并且它们会引发振幅更大的事件相关电位（ERP）成分。由于人格被认为是影响这些成分以及我们行为差异的生物学相关因素之一，因此研究人格如何影响我们在不同相关任务中的自我意识及其神经学基础具有重要意义。
马来西亚理科大学（USM）的33名男女本科医学生参与了该研究。使用USM人格量表问卷将参与者分为两组，即中间型（= 18）和外向型（= 15）组。在ERP实验中，在三刺激视觉Oddball范式中，分别以58%、21%和21%的时间呈现包含除自我和非自我相关名词之外的任何单词的标准刺激的方块（例如， 、 、 等；英文分别为：Ball、Teeth、Kids等）、包含自我相关代词（ 、 或 ；英文分别为：I、Us或We）的方块以及包含非自我相关代词（ 、 或 ；英文分别为：He/She、You或They）的方块。所有单词均以马来语呈现。参与者被指示对自我相关的单词按1，对非自我相关的单词按2，并忽略标准刺激。
外向型组中自我相关和非自我相关代词的N200和P300振幅比较显示，在七个电极部位存在显著差异，自我相关代词在前部电极处的振幅较大，在后部电极处的振幅较小。在中间型组中未观察到这种情况。
本研究表明，自我相关代词对外向者在心理上比对外向-内向中间型者更重要；因此，他们有更强的自我意识。这可能是由于外向者大脑中大量的多巴胺，其在额叶中更为集中。
