Memory and Learning in WAG/Rij and Sprague Dawley Rats: Investigating the Effect of “Racial Experience,” Especially on Predisposition to Epilepsy

Abstract

This research sought to investigate how genetic variations influence learning, short-term memory, and long-term memory in rats. In particular, it compared WAG/Rij (WR) rats, which are naturally prone to epilepsy, with Sprague-Dawley (SD) rats. A total of 24 male rats, consisting of 12 Sprague-Dawley (SD) and 12 Wistar (WR) rats, were evaluated using an eight-arm radial maze to examine spatial memory and the retention of learning over time. No significant differences were observed in working memory errors (WME) at 48, 72, 96, 120, and 144 hours (p > 0.05), and similar results were found for reference memory errors (RME). However, WR rats made significantly more RME than SD rats at 48 hours (p = 0.0111, 95% CI: -1.606 to -0.2178). SD rats also completed the maze significantly faster at 96 hours (p = 0.0094) and 120 hours (p = 0.0383) than WR rats. Additionally, on the 4th day of the acquisition trial, WR rats made significantly more total errors than SD rats (p = 0.0045). This research offers fresh perspectives on the variations in learning and memory across different rat strains within various behavioral models. Although SD rats gave better results in short-term memory and faster results in the process of completing the task compared to WR rats, further research is recommended in different behavioral patterns.

Keywords

• Racial Experience
• Reference Memory
• Spatial Learning
• Working Memory

WAG/Rij ve Sprague Dawley Sıçanlarında Hafıza ve Öğrenme: “Irksal Deneyimin” Özellikle Epilepsi Yatkınlığının Üzerindeki Etkisinin Araştırılması

Abstract

Bu araştırma, genetik varyasyonların sıçanlarda öğrenmeyi, kısa süreli hafızayı ve uzun süreli hafızayı nasıl etkilediğini araştırmayı amaçlamıştır. Özellikle, doğal olarak epilepsiye yatkın olan WAG/Rij (WR) sıçanlarını Sprague-Dawley (SD) sıçanlarıyla karşılaştırmıştır. 12 Sprague-Dawley (SD) ve 12 Wistar (WR) sıçanından oluşan toplam 24 erkek sıçan, uzaysal hafızayı ve zaman içinde öğrenmenin tutulmasını incelemek için sekiz kollu bir radyal labirent kullanılarak değerlendirilmiştir. 48, 72, 96, 120 ve 144. saatlerde çalışma belleği hatalarında (WME) anlamlı bir fark gözlenmemiştir (p > 0,05) ve referans bellek hataları (RME) için benzer sonuçlar bulunmuştur. Bununla birlikte, WR sıçanları 48. saatte SD sıçanlarına göre anlamlı derecede daha fazla RME yapmıştır (p = 0,0111, %95 GA: -1,606 ila -0,2178). SD sıçanları ayrıca labirenti 96 saatte (p = 0,0094) ve 120 saatte (p = 0,0383) WR sıçanlarından önemli ölçüde daha hızlı tamamladı. Ek olarak, edinim denemesinin 4. gününde, WR sıçanları SD sıçanlarından önemli ölçüde daha fazla toplam hata yaptı (p = 0,0045). Bu araştırma, çeşitli davranış modelleri içindeki farklı sıçan türleri arasında öğrenme ve bellekteki farklılıklar hakkında yeni bakış açıları sunmaktadır. SD sıçanları kısa süreli bellekte daha iyi sonuçlar ve görevi tamamlama sürecinde WR sıçanlarına kıyasla daha hızlı sonuçlar vermiş olsa da, farklı davranış kalıplarında daha fazla araştırma yapılması önerilmektedir.

Keywords

• Çalışma Belleği
• Irksal Deneyim
• Mekansal Öğrenme
• Referans Belleği

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