Sleep consolidates memories for competing tasks

Sleep Consolidation of Interfering Auditory Memories in Starlings
Brawn TP, Nusbaum HC, Margoliash D.
Psychological Science 2013, published on Feb 22

Memory consolidation has been described as a process to strengthen newly formed memories and to stabilize them against interference from similar learning experiences. Sleep facilitates memory consolidation in humans, improving memory performance and protecting against interference encountered after sleep. The European starling, a songbird, has also manifested sleep-dependent memory consolidation when trained on an auditory-classification task. Here, we examined how memory for two similar classification tasks is consolidated across waking and sleep in starlings. We demonstrated for the first time that the learning of each classification reliably interferes with the retention of the other classification across waking retention but that sleep enhances and stabilizes the memory of both classifications even after performance is impaired by interference. These observations demonstrate that sleep consolidation enhances retention of interfering experiences, facilitating opportunistic daytime learning and the subsequent formation of stable long-term memories

Get enough sleep - children

Experts recommend that children should get the following amount of sleep at each stage of growth:
  • 3 months – 1 year: About 14 to 15 hours a day 
  • 1 – 3 years: 12 to 14 hours a day 
  • 3 – 5 years: 11 to 12 hours of sleep a day 
  • 6 – 12 years: 10 to 11 hours a day 
  • 12 – 18 years: 8.5 to 9.5 hours a day

Lucidity and consciousness in dreams

Measuring consciousness in dreams: The lucidity and consciousness in dreams scale
Ursula Vossa, Karin Schermelleh-Engela, Jennifer Windtc, Clemens Frenzeld, Allan Hobsone
Consciousness and Cognition, Volume 22, Issue 1, March 2013, Pages 8–21 

Both lucid and non-lucid dreams are an important contrast condition for theories of waking consciousness, giving valuable insights into the structure of conscious experience and its neural correlates during sleep. However, the precise differences between lucid and non-lucid dreams remain poorly understood. The construction of the Lucidity and Consciousness in Dreams scale (LuCiD) was based on theoretical considerations and empirical observations. Exploratory factor analysis of the data from the first survey identified eight factors that were validated in a second survey using confirmatory factor analysis: INSIGHT, CONTROL, THOUGHT, REALISM, MEMORY, DISSOCIATION, NEGATIVE EMOTION, and POSITIVE EMOTION. While all factors are involved in dream consciousness, realism and negative emotion do not differentiate between lucid and non-lucid dreams, suggesting that lucid insight is separable from both bizarreness in dreams and a change in the subjectively experienced realism of the dream.