A Nap But Not Rest or Activity Consolidates Language Learning

Abstract

Recent evidence suggests that a period of sleep after a motor learning task is a relevant factor for memory consolidation. However, it is yet open whether this also holds true for language-related learning. Therefore, the present study compared the short- and long-term effects of a daytime nap, rest, or an activity task after vocabulary learning on learning outcome. Thirty healthy subjects were divided into three treatment groups. Each group received a pseudo-word learning task in which pictures of monsters were associated with unique pseudo-word names. At the end of the learning block a first test was administered. Then, one group went for a 90-min nap, one for a waking rest period, and one for a resting session with interfering activity at the end during which a new set of monster names was to be learned. After this block, all groups performed a first re-test of the names that they initially learned. On the morning of the following day, a second re-test was administered to all groups. The nap group showed significant improvement from test to re-test and a stable performance onto the second re-test. In contrast, the rest and the interference groups showed decline in performance from test to re-test, with persistently low performance at re-test 2. The 3 (GROUP) × 3 (TIME) ANOVA revealed a significant interaction, indicating that the type of activity (nap/rest/interfering action) after initial learning actually had an influence on the memory outcome. These data are discussed with respect to translation to clinical settings with suggestions for improvement of intervention outcome after speech-language therapy if it is followed by a nap rather than interfering activity.

Sleep-Dependent Consolidation of Second Language Grammar Knowledge

“…Five participants were excluded because they reported napping during the waking interval. Even a short period of sleep can consolidate language learning (see Heim et al, 2017). The remaining 100 participants (64 women, 36 men) were randomly assigned to the Wake (n = 53, M age = 22.04, SD = 5.36) or Sleep (n = 47, M age = 23.83, SD = 8.90) conditions.…”

Effects of Sleep on Language and Motor Consolidation: Evidence of Domain General and Specific Mechanisms

“…To wit, performance on recall tests of the newly learnt vocabulary, 12 to 24 hours post training, shows a stabilizing effect when sleep is afforded immediately after training compared to an equivalent period of wakefulness (Gais et al, 2006;Tamminen et al, 2010). Moreover, other studies even reported offline gains, measured as an increase in the number of recalled words or a reduction in reaction time following night's sleep compared to performance immediately after training (Dumay & Gaskell, 2007;Heim et al, 2017;Henderson et al, 2012).…”

Benefits and risks of napping in older adults: A systematic review

“…These studies were published between 1995 and 2021, arranged by order of publication date. Five studies were conducted in the USA (Creighton, 1995;Campbell et al, 2005;Baran et al, 2016;Scullin et al, 2017;Fitzroy et al, 2021), five in Canada (Monk et al, 2001;Milner and Cote, 2008;Fogel et al, 2014;King et al, 2017;Fang et al, 2021), two in Japan (Tamaki et al, 1999(Tamaki et al, , 2000, two in Germany (Backhaus et al, 2016;Heim et al, 2017), and one in Israel (Korman et al, 2015). Included studies focused on the effects of napping on perceptual measures [i.e., subjective sleepiness (Creighton, 1995;Tamaki et al, 1999Tamaki et al, , 2000Milner and Cote, 2008;Fogel et al, 2014;Backhaus et al, 2016;Fang et al, 2021;Fitzroy et al, 2021), subjective fatigue (Tamaki et al, 1999(Tamaki et al, , 2000Milner and Cote, 2008) and subjective alertness (Monk et al, 2001)], reaction time (Creighton, 1995;Tamaki et al, 1999;Monk et al, 2001;Milner and Cote, 2008;Backhaus et al, 2016), memory (Milner and Cote, 2008) and psychomotor performance (Monk et al, 2001;Campbell et al, 2005;Fogel et al, 2014), declarative (Backhaus et al, 2016;…”

“…The number of participants in each trial ranged from 6 (Creighton, 1995;Tamaki et al, 1999) to 45 (Scullin et al, 2017), with a mean sample size of 21.73 (SD 12.08). Mean age ranging from 60.8 (Heim et al, 2017) to 78.3 (Monk et al, 2001) years.…”