The Relationship Between Sleep and Declarative Memory

Sleep is a physiologically active process and the function of cognitive processes is known for a long time. It is also known that sleep has a crucial role in two distinct phases of memory. The first one is the information encoding phase which is prior to the learning process; and the second one is the consolidation phase which is related with the persistency of new information after learning occurs. Consolidation is thought as a function of evolutionarily preserved sleep for many forms of memory. The aim of this review is to get together the main study findings which investigating the relationship between the micro and macro structures of sleep and declarative memory processes. Firstly, definition of sleep is given, and then the specific role of sleep in declarative memory consolidation process is explained. In this context, the projected active system consolidation and synaptic homeostasis hypothesis are explicated. The study results investigating the effects of sleep deprivation on declarative memory and information processing phases are summarized. Finally, the role of sleep spindle and slow wave activity on memory processes, which make up the microstructure of sleep, is discussed

Construct validity of auditory verbal learning test

Amaç: İşitsel Sözel Öğrenme Testi (Auditory Verbal Learning Test: AVLT) nöropsikoloji yazınında, belleğin kapsamlı değerlendirilmesi için sıklıkla kullanılan bir ölçüm aracıdır. Test sözel öğrenmeyi; anlık ve gecikmeli serbest hatırlama, tanıma türü hatırlama, geriye ve ileri doğru bozucu etki olarak ölçmektedir. Türk toplumuna uyarlama çalışmaları yapılmış olan AVLT’nin araştırma ve geliştirme (AR-GE) çalışmaları sürmektedir. Mevcut çalışmanın amacı; testin AR-GE sürecine katkı sağlamak amacıyla kurutlu geçerliğini incelemektir. Yöntem: Mevcut amaç doğrultusunda 20-69 yaş aralığında, tanılanmış herhangi bir psikiyatrik veya nörolojik rahatsızlığın bulunmayan; düzeltilmemiş görme ve işitme bozukluğu bulunmayan 78 sağlıklı katılımcıdan veriler elde edilmiştir. AVLT bu testi uygulama eğitimi almış iki psikolog tarafından, katılımcılara bireysel olarak uygulanmıştır. Bulgular: AVLT puanlarının temsil ettikleri özellik kümelerini incelemek amacıyla uygulanan temel bileşenler analizi, testin yapısıyla uyumlu olarak öğrenme ve serbest hatırlama, tanıma türü hatırlama bileşenlerini ayrı ayrı içermiştir. Yapısal Eşitlik Modeli (YEM) çalışmasında ise bu iki bileşene çeldiricilerin etkisi eklenmiştir. Yaş, eğitim ve cinsiyetin AVLT puanlarıyla ilişkisini belirlemek amacıyla, betimsel düzeyde incelemeler yapılmıştır. Sonuç: Belleğin gelişimsel süreçten etkilendiği yolundaki yazınla uyumlu olan bu bulgular AVLT’nin öğrenme/serbest hatırlama, tanıma ve çeldirici puanlarının kuramsal bilgiyle uyumlu bir bileşen örüntüsü gösterdiğini ortaya koymaktadır. Bu sonuç Türk toplumunda testin, geçerli bir ölçme aracı olduğuna işaret etmektedir.Objective: Auditory Verbal Learning Test (AVLT) is frequently used in neuropsychology literature to comprehensively assess the memory. The test measures verbal learning as immediate and delayed free recall, recognition, and retroactive and proactive interference. Adaptation of AVLT to the Turkish society has been completed, whereas research and development studies are still underway. The purpose of the present study is to investigate the construct validity of the test in order to contribute to the research and development process. Method: In line with this purpose, the research data were obtained from 78 healthy participants aged between 20 and 69. The exclusion criteria included neurological and/or psychiatric disorders as well as untreated auditory/visual disorders. AVLT was administered to participants individually by two trained psychologists. Results: Principal component analysis that is used to investigate the components represented by the AVLT scores consisted of learning, free recall and recognition, in line with the construct of the test. Distractors were also added to these two components in structural equation model. Analyses were carried out on descriptive level to establish the relatioships between age, education, gender and AVLT scores. Conclusion: These findings, which are consistent with the literature indicating that memory is affected by the developmental process, suggest that learning/free recall, recognition, and distractor scores of the AVLT demonstrate a component pattern consistent with theoretical knowledge. This conclusion suggests that AVLT is a valid measurement test for the Turkish society

Construct validity of auditory verbal learning test

OBJECTIVE: Auditory Verbal Learning Test (AVLT) is frequently used in neuropsychology literature to comprehensively assess the memory. The test measures verbal learning as immediate and delayed free recall, recognition, and retroactive and proactive interference. Adaptation of AVLT to the Turkish society has been completed, whereas research and development studies are still underway. The purpose of the present study is to investigate the construct validity of the test in order to contribute to the research and development process. METHOD: In line with this purpose, the research data were obtained from 78 healthy participants aged between 20 and 69. The exclusion criteria included neurological and/or psychiatric disorders as well as untreated auditory/visual disorders. AVLT was administered to participants individually by two trained psychologists. RESULTS: Principal component analysis that is used to investigate the components represented by the AVLT scores consisted of learning, free recall and recognition, in line with the construct of the test. Distractors were also added to these two components in structural equation model. Analyses were carried out on descriptive level to establish the relatioships between age, education, gender and AVLT scores. CONCLUSION: These findings, which are consistent with the literature indicating that memory is affected by the developmental process, suggest that learning/free recall, recognition, and distractor scores of the AVLT demonstrate a component pattern consistent with theoretical knowledge. This conclusion suggests that AVLT is a valid measurement test for the Turkish society