Sains Malaysiana 42(6)(2013): 765–771

Interaksi Psikofisiologi antara Girus Presentral dan Lobus Parietal Superior Kanan

(Psychophysiologic Interaction between Right Precentral Gyrus and Superior Parietal Lobule)

A.N. Yusoff*

Program Pengimejan Diagnostik & Radioterapi, Pusat Pengajian Sains Diagnostik

& Kesihatan Gunaan, Fakulti Sains Kesihatan, Universiti Kebangsaan Malaysia

Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Malaysia

Diserahkan: 2 Oktober 2012/Diterima: 14 November 2012

ABSTRAK

Kajian pengimejan resonans magnet kefungsian (fMRI) subjek tunggal ini menyelidiki interaksi psikofisiologi (PPI) antara girus presentral (PCG) dan lobus parietal superior (SPL) kanan semasa tepikan jari rentak sendiri secara bilateral. Model kehubungan efektif antara PCG dan SPL kanan dibina menggunakan analisis PPI dengan mengambil daya dan laju tepikan sebagai faktor uji kaji. Keputusan menunjukkan bahawa peningkatan daya dan laju tepikan masing-masing mengaktifkan PCG bilateral dan SPL kanan secara bererti (p<0.05). PCG dan SPL kanan didapati saling berhubungan semasa tepikan jari dilakukan dengan daya dan laju tepikan sebagai faktor uji kaji yang mempengaruhi kehubungan efektif antara mereka. Kajian ini telah mendedahkan maklumat asas berguna untuk kajian fMRI pada masa depan ke atas koordinasi motor dan boleh digunakan untuk mengkaji ketaktertiban otak misalnya strok.

Kata kunci: fMRI; kehubungan efektif; pemetaan statistik berparameter; tepikan jari

ABSTRACT

This single participant functional magnetic resonance imaging (fMRI) study investigated the psychophysiologic interaction (PPI) between the right precentral gyrus (PCG) and superior parietal lobule (SPL) during bilateral self-paced tapping of hand fingers with the tapping force and speed as experimental factors. The effective connectivity model between the right PCG and SPL was established using PPI analysis. The results indicated that the increase in tapping force and speed significantly (p<0.05) activate bilateral PCG and right SPL, respectively. The right PCG and SPL were found to be interconnected when finger tapping is performed with the tapping force and speed as the experimental factors that influenced the effective connectivity between them. This study has revealed useful fundamental information for future fMRI studies on motor coordination and is implementable in studying brain disorders such as stroke.

Keywords: Effective connectivity; finger tapping; fMRI; statistical parametric mapping

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*Pengarang untuk surat-menyurat; email: nazlim@fskb.ukm.my