Table 1:

Summary of studies reviewed in the systematic analysis.

Learning Type	Task	Rule Type	Study	N	Subjects	Design	Sleep Time	Implicit Effect	Explicit effect	Sleep correlates
Insight	NRT	T	Wagner et al., 2004 [9]	106	Adults	Sleep vs. Wake	Overnight	No	Yes	-
	NRT	T	Yordanova et al., 2008 [31]; 2009a [90], 2009b [91], 2010 [92], 2012 [12]	55	Adults	SWS-rich vs. REM-rich	Overnight	No	Yes	SWS
	NRT	T	Debarnot et al., 2017 [93]	74	Adults, Elderly	Sleep vs. Wake Young vs. Old	Overnight	-	Yes (young) No (elderly)	-
	Virtual Map Insight	T	Lerner & Gluck, 2018 [32]	20	Adults	Single Sleep Group	Multiple Nights	Yes	No	SWS
	Surveillance	T	Lerner et al., 2019 [33]	24	Adults	Cue vs. sham	Overnight	Yes	Indirect a	nREM
Visuo-Motor Sequence Learning	SRTT	T	Maquet et al., 2000 [37]; Peigneux et al., 2003 [94]	31	Adults	Sleep vs. Wake b Structured vs. Random	Overnight	Yes	No	REM
	SRTT	T	Robertson et al., 2004 [34] (implicit instructions condition)	36	Adults	Sleep vs. Wake	Overnight	No	No	-
	SRTT	T	Robertson et al., 2005 [95]	44	Adults	Sleep vs. Wake	Overnight	Yes (some conditions) c	No	-
	SRTT	T	Spencer et al., 2006 [76], (implicit instructions condition)	50	Adults	Sleep vs. Wake	Overnight	Yes (some conditions) d	No	-
	SRTT	T	Spencer et al., 2007 [96], (implicit instructions condition)	16	Elderly	Sleep vs. Wake	Overnight	No	No	-
	SRTT	T	Ertelt et al., 2012 [97]	37	Adults	Sleep vs. Wake	Overnight	Yes	No	-
	SRTT	T	Pace-Schott & Spencer, 2013 [98]	112	Adults, Elderly	Sleep vs. Wake	Overnight	Yes (young) No (elderly)	No	-
	SRTT	T	Wilhelm et al., 2013 [39]	161	Children, Adults	Sleep vs. Wake	Overnight	-	Yes	SWS
	SRTT	T	Song et al., 2014 [99] (unintentional group)	40	Adults	Sleep vs. Wake	Overnight	No	No	-
	SRTT	T	Cousins et al., 2014 [100]	32	Adults	Cueing before vs. during sleep	Overnight	Yes	Yes	SWS, Spindles
	SRTT	T	Kirov et al., 2015 [101]	53	Adults	Single sleep group	Overnight	-	Yes	nREM-REM tr.
	SRTT	T	Diekelmann et al., 2016 [40]	36	Men, Women	Cue vs. sham	Overnight	No	Yes (men) No (women)	SWS
	SRTT	T	Cousins et al., 2016 [64]	22	Adults	Single sleep group, cued vs. uncued target	Overnight	Yes	Indirect e	SWS, REM
	SRTT	T	Zinke et al., 2017 [102]	25	Children	Single sleep group	Overnight	No	Yes	Spindles
	SRTT	T	Yordanova et al., 2017 [103]	53	Adults	Single sleep group	Overnight	No	Yes	Spindles
	SRTT	T	Lutz et al., 2018 [104]	117	Adults	Sleep vs. Wake	Overnight	Yes	Yes f	-
	Ocular SRTT	T	Albouy et al., 2006 [105]	49	Adults	Sleep vs. Wake	Overnight	Yes	No	-
	ASRT	T	Song et al., 2007 [36]	36	Adults	Sleep vs. Wake	Overnight	No	No	-
	ASRT	T	Nemeth et al., 2010 [41]	25	Adults, Elderly	Sleep vs. Wake	Overnight	No	No	-
	ASRT	T	Hallgato et al., 2013 [106]	102	Adults	Sleep vs. Wake	Overnight	No	No	-
	ASRT	T	Csabi et al., 2014 [107]	34	Adults	OSA vs. control	Overnight	No	No	-
	High-order SRTT	T	Fischer et al., 2006 [11]	20	Adults	Sleep vs. Wake	Overnight	No	Yes	-
	High-order SRTT	T	Fischer et al., 2007 [35]	25	Children, Adults	Sleep vs. Wake	Overnight	No (children) Yes (adults)	-	-
	High-order SRTT	T	Drosopoulos et al., 2011 [81]	40	Adults	Sleep vs. SD	Overnight	-	Yes	-
Statistical Learning	Tone Learning	T	Durrant et al., 2011 [14]	36	Adults	Sleep vs. Wake	Overnight	Yes	-	SWS
	Tone Learning	T	Durrant et al., 2012 [49], 2016 [50]	48	Adults	Sleep vs. Wake	Nap	Yes	-	SWS
	Tone Learning	T	Hennies et al., 2017 [108]	42	Adults	Cue at sleep vs. wake	Overnight	Yes	-	SWS
	WPT	S	Djonlagic et al., 2009 [28]	99	Adults	Sleep vs. Wake	Overnight	Yes (some conditions)	Indirect (some conditions) g	REM
	WPT	S	Barsky et al., 2015 [47]	51	Adults	Sleep vs. Wake	Nap	Yes	-	REM
	WPT	S	Kemeny & Lukacs, 2016 [109]	44	Adults	Sleep vs. Wake	Overnight	No	-
	WPT	S	Lerner et al., 2016 [48] (experiment 2)	20	Adults	Single sleep group	Multiple Nights	Yes	-	SWS, N1/N2
Artificial Grammar Learning (AGL)	AXB words	T	Gomez et al., 2006 [5]	48	Infants	Sleep vs. Wake	Nap	Yes	-	-
	AXB words	T	Hupbach et al., 2009 [61]	48	Infants	Sleep vs. Wake	Nap	Yes	-	-
	AXB words	T	Frost & Monaghan et al., 2017 [62]	72	Adults	Sleep vs. Wake	Overnight	Yes	-	-
	Syllable regularity	S h	Gaskell et al., 2014 [45]	38	Adults	Single cued sleep group	Nap	Yes	No	SWS
	“Reber”-like Grammar 1	T	Nieuwnhuis et al., 2013 [110]	81	Adults	Sleep vs. Wake	Overnight	Yes	-	-
	“Reber”-like Grammar 2	T	Kemeny & Lukacs, 2016 [109]	45	Adults	Sleep vs. Wake	Overnight	No	-	-
	“Reber”-like Grammar 3	S g	Batterink & Paller, 2017 [44]	44	Adults	Single cued sleep group	Nap	Yes	No	SWS
	Segmentation	T	Simon et al., 2017 [46]	37	Infants	Sleep vs. Wake	Nap	Yes	-	SWS
Relational Memory	Transitive Inference	S	Ellenbogen et al., 2007 [4]	56	Adults	Sleep vs. Wake	Overnight	Yes	No	-
	Transitive Inference	S	Werchen & Gomez, 2013 [42]	64	Adults	Sleep vs. Wake	Overnight	Yes	No	-
	Associative Inference	S	Lau et al., 2010 [13]	31	Adults	Sleep vs. Wake	Nap	Yes	-	SWS
	Associative Inference	S	Alger & Payne, 2016 [43]	58	Adults	Sleep vs. Wake	Nap	Yes	-	REM
Information-Integration	Frequency-Orientation Associations	S	Maddox et al., 2009 [30]	49	Adults	Sleep vs. SD	Overnight	Yes	-	-
	Visual-Audio Associations	S	Hennies et al., 2014 [29]	52	Adults	Sleep vs. Wake	Overnight	No	No i	-
	Tone-Density Associations	S	Ashton et al., 2018 [51]	95	Adults	Sleep vs. Wake	Overnight	Yes j	No	-
Generalization of Categorical Learning	Prototypes (AB task)	S	Maddox et al, 2011 [58]	18	Adults	Sleep vs. SD	Overnight	No	-	-
	Objects	S	Werchan & Gomez, 2014 [60]	27	Infants	Sleep vs. Wake	Nap	No	-	-
	Dot Pattern	S	Graveline & Wamsley, 2017 [56]	73	Adults	Sleep vs. Wake	Overnight	Yes	-	-
	Satellites	S	Schapiro et al., 2017 [59] (novel items condition)	193	Adults	Sleep vs. Wake	Overnight, Nap	-	No	REM k
	Abstract images	S	Lutz et al., 2017 [57]	28	Adults	Sleep vs. Wake	Overnight	No l	-	REM k
	Movies	T	Sandoval et al., 2017 [55]	79	Children	Sleep vs. Wake	Nap	Yes	-	-
	Novel objects	S	Friedrich et al., 2015 [52]	90	Infants	Sleep vs. Wake	Nap	Yes	-	Spindles
	Novel objects	S	Friedrich et al., 2017 [53]	107	Infants	Sleep vs. Wake	Nap	Yes	-	Spindles, N2
	Novel objects	S	Friedrich et al., 2019 [54]	30	Infants	Single sleep group	Nap	Yes	-	Spindles

Note: T and S in the ‘Rule type’ column refers to Temporal and Stationary regularities, respectively; ASRT, Alternating Serial Response Time task; nREM, non-REM; NRT, Number Reduction Task; OSA, Obstructive sleep apnea; REM, Rapid Eye Movement; SD, Sleep Deprivation; SRTT, Serial Reaction Time Task; SWS, Slow Wave Sleep; tr, transitions; WPT, Weather Prediction Task;

^aCueing during sleep was correlated to implicit measures, which themselves were strongly influenced by explicit rule detection;

^bWake and sleep groups were compared in order to identify brain regions showing higher activation during REM sleep; then, those regions were used to detect correlations with performance improvement for a sleep group that trained on structured sequences compared to a group that trained on random sequences;

^csleep was shown to prevent the obstruction of regularities extraction caused by Transcranial Magnetic Stimulation (TMS) delivered following training; without TMS, however, no sleep effect was found;

^dsleep effect found only in the ‘contextual’ condition where additional hidden hints regarding the regularity were present;

^eno effects of cueing on explicit behavioral measures, but existing correlations between explicit measures and brain measures;

^fExplicit effects found for confidence ratings of a generation task (‘triplet completion’), though not for generation accuracy;

^gexplicit rule knowledge not examined, but sleep was shown to facilitate explicit evaluation of simple stimulus-response probabilities when conditions prevented pre-sleep training performance to approach ceiling levels;

^hstimuli were words presented visually that were also read aloud; thus, the hidden rule could be discovered based on extraction of either stationary or temporal regularities;

ⁱexplicit measurements were based on metrics from three additional tests. Although none of these tests directly required to state the hidden two-dimensional rule, one was reminiscent of a generation test (i.e., requiring to generate new examples of the rule) as defined in Methods;

^jno effects immediately following sleep, but sleep affected the ability to relearn the stimuli a week later;

^kREM sleep was associated to performance in memory tests but not in generalization tests (which were absent);

^lEffects were not found immediately following sleep; some sleep effects were found a year later, but at that point the generalization items were not totally novel.