Nasir Yusoff

The Effect of Sex on the Electropsychological Process of Emotional Arousal Intensity

Background Sex is a psychobiological factor that is important in the process of emotion. This study determines the effect of sex on the electropsychological process of various intensities of emotional arousal. Methods In the Event-related Potential (ERP) session, electroencephalographic (EEG) data was recorded for 90 participants, 60% of whom were females. The participants responded to 30 universal emotional pictures, randomly chosen from the International Affective Picture System (IAPS), which were classified as invoking high, moderate, and low intensity of emotional arousal. Results From the analysis of variance of two-way mixed design, the interaction between sex and emotional intensity was observed in the occipital regions (O2), indexed by the amplitude of P300 and N200 components. Males exhibited higher amplitude of P300 and N200 components (in the occipital region) as responded to high and low emotional arousal stimuli than females. Conclusion Sex is a fundamental factor that modulates psychological states in reaction to emotional stimuli.

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.

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, Kami or Kita; in English: I, Us or We, respectively), and non-self-related pronouns (Dia, Anda or Mereka; 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. CONCLUSION 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.

Electrophysiological quantification of underlying mechanism of decision making from auto dealers advertisement – A neuromarketing research

This study focused on which display design of advertisement that would be able to attract most attention by measuring cognitive response and gaze behavior. Total of 15 subjects were recruited from USM undergraduate medical students. The event related potential (ERP) as a cognitive response during viewing different display design were recorded from 17 electrode sites using 128 electrode sensors net which was applied on the subject’s scalp according to the 10-20 international electrode placement system. The amplitude of the evoked N100 and P300 ERP components were identified. To determine the statistical significance, amplitude data were analyzed using one way ANOVA test and reaction time was analyzed using Independent t-test. Two out of the 15 subjects participated in the ERP recording in order to measure the fixation duration, pupil size and attention maps of eye movement as a gaze behavioral response to the different display design using Eye Tracking. The ERP and the gaze behavior results were consistent...