Çalışma Belleğine Ait OİP Temelli Elektrofizyolojik Bulguların İncelenmesi

Year 2018, Volume: 3 Issue: 2, 106 - 115, 27.12.2018

Selen Güney , Seray Şenyer Özgör Cansın Özgör Adil Deniz Duru

Abstract

Uyaranların etkisi ile gözlemlenen Olaya İlişkin Potansiyel (OİP) bileşenleri çalışma belleği araştırmalarında

önemli bir yer tutmaktadır. Çalışma belleği temelde karmaşık bilişsel görevleri yürütme, bilgileri geçici

olarak saklama ve kullanma imkanı veren zihinsel bir süreç olarak bilinmektedir. Çalışmanın amacı;

çalışma belleği kavramının, bilişsel süreçler sırasında beyinde oluşan elektriksel yanıtlar ile anlaşılmasının

sağlamasıdır. Araştırmaya Marmara Üniversitesi’nden toplamda 21 katılımcı yaş ortalaması 21 olan 1 kadın

ve yaş ortalaması 22.95 (SS= 5.549) olan 20 erkek sporcu katılmıştır. EEG kaydı 16 kanal Brain Products

actiCAP ile 1000 Hz örneklem frekansında alınmıştır. N-geri görevi olarak katılımcılara LCD ekran aracılığı

ile siyah ekran üzerine beyaz fontlarla yazılmış 8 adet harf ( B, Q, X, F, M, K, H, R) rastgele ve bir sette 25

harf olacak şekilde 8 set halinde gösterilmiştir. Deneyden toplanan verilerin analizleri için Brain Products

Analyzer, Matlab R2013 ve SPSS v17 paket programları kullanılmıştır. Verilerin istatistiksel analizi Çok

Değişkenli Varyans Analizi (ANOVA) kullanılarak yapılmıştır. Çalışmanın elektrofizyolojik analizleri,

ortalama güç değerleri kapsamında incelendiğinde frontal, santral, oksipital ve parietal alanda anlamlı

farklılıklar bulunmuştur (F=(2.19)=17.43; p=0.00). Ortalama zaman değerleri kapsamında incelendiğinde

ise yine frontal, santral, oksipital ve parietal alanda anlamlı farklılıklar bulunmuştur (F=(4,76)=10.07;

p=0.00). Fakat ortalama frekans değerleri incelendiğinde anlamlı bir fark olmadığı görülmüştür.

Katılımcıların uyaranlara karşı reaksiyon zamanları; basması gerekip bastığı (doğru durum) ve basmaması

gerekip bastığı (yanlış durum) şeklinde incelendiğinde basması gerekip bastığı durumun, basmaması

gerekip bastığı durumdan daha önce yaşandığı görülmüştür. Bu sonuçlar ışığında N-geri görevinin çalışma

belleği ve dikkat süreçlerini anlama konusunda kullanışlı bir araç olduğu düşünülmektedir.

Keywords

Çalışma belleği, N-geri görevi, Reaksiyon zamanı

Assesment of ERP Based Electrophysiological Findings of Working Memory

Abstract

The Event Related Potential (ERP) components that are observed in response to the stimuli play an

important role in working memory research. The working memory is known as a mental process that

basically allows the use of complex cognitive tasks, the ability to temporarily store and use information.

The purpose of this study is to understand the concept of the working memory and electrical responses

of the brain during cognitive processes. A total of 21 participants from Marmara University, 1 female

(mean age=21) and 20 male (mean age=22.95, SD=5.54) athletes voluntarily participated in the study. EEG

recordings were performed with 16 channel Brain Products actiCAP at 1000 Hz sampling frequency. 8

letters (B, Q, X, F, M, K, H, R) written in white on a black screen were used as stimuli. All stimuli randomly

presented in 8 sets with each set consisting of 25 letters. An LCD screen was used as presentation apparatus.

For the analysis of the data, Brain Products Analyzer, MatlabR2013 software program and SPSS17 package

program were used. Statistical analyzes of the data were done using Multivariate Analysis of Variance

(ANOVA). Electrophysiological analysis of the study showed significant differences in frontal, central,

occipital and parietal areas (F (2.19) = 17.43; p = 0.00). When the mean time values were examined,

significant differences were found in frontal, central, occipital and parietal areas (F = (4.76) = 10.07; p =

0.00). However, there was no significant difference in the mean frequency values. When the participants’

reaction times were examined, it is found that they press the button faster for the stimuli they need to

pres (correct situation) then they fort he stimuli they should not pres (wrong situation). In light of these

results, it is thought that the N-back task can provide a illuminating results to understand working memory

processes.

Keywords

Working Memory, N-back ask, Reaction Time

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