title: How Much We Think of Ourselves and How Little We Think of Others: An Investigation of the Neuronal Signature of Self-Consciousness between Different Personality Traits through an Event-Related Potential Study.
abstract: BACKGROUND
  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.
  
  
  METHODS
  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 (n= 18) and Extravert (n= 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.,Bola,Gigi,Anak, etc.; in English: Ball, Teeth, Kids, etc., respectively), those containing self-related pronouns (Saya,KamiorKita; in English: I, Us or We, respectively), and non-self-related pronouns (Dia,AndaorMereka; 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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Neurosciences, School of Medical Science, Universiti Sains Malaysia, Health Campus, 16150 Kubang Kerian, Kelantan, Malaysia.
authors.forename: Auwal Bello
authors.initials: AB
authors.lastname: Hassan
authors.affiliation: Department of Neurosciences, School of Medical Science, Universiti Sains Malaysia, Health Campus, 16150 Kubang Kerian, Kelantan, Malaysia.
authors.forename: Tahamina
authors.initials: T
authors.lastname: Begum
authors.affiliation: Department of Neurosciences, School of Medical Science, Universiti Sains Malaysia, Health Campus, 16150 Kubang Kerian, Kelantan, Malaysia.
authors.forename: Mohammed Faruque
authors.initials: MF
authors.lastname: Reza
authors.affiliation: Department of Neurosciences, School of Medical Science, Universiti Sains Malaysia, Health Campus, 16150 Kubang Kerian, Kelantan, Malaysia.
authors.forename: Nasir
authors.initials: N
authors.lastname: Yusoff
keywords: N200 evoked potentials; P300 component; extraversion