Evolution of sleep in relation to memory – a birds’ brain view

Abstract

Sleep’s role in memory consolidation is widely accepted. However, the role of the different sleep states and accompanying neurophysiological activity is still actively debated. Most theories of sleep-related memory consolidation are based on studies in a few mammalian species. Recent evidence from research in birds, which exhibit sleep states that are in most respects similar to those found in mammals (despite being distantly related) suggests that the way some types of memories are consolidated during sleep might be different in taxa other than mammals. This review will discuss how the recent sleep-related neurophysiological findings in birds inform our understanding of memory consolidation during sleep.