Question

Correlations between recognition performance and sleep parameters showed that in the sleep condition overall mem ory accuracy was strongly correlated with the amount of NonREM sleep during consolidation sleep (r-.79, p 007; Fig. 2a). Hit rate or false alarm rate alone were not significantly associated with NonREM sleep (r-.36, p-.31, and r42, p-.23, respectively). Separate analy- ses for the three valence categories of facial expression revealed that the association between memorv accuracy and NonREM sleep was significant for angry and happy, but not neutral faces (angry: r-.79, p-.006, happy: r-.86 p-.001, neutral: r-.03, p-.93). The same pattern, although less pronounced, was found for the correlation between memory accuracy and total sleep time in the night after learning (all faces: r-.65 r66, p037, angry faces: r-.61, p .11, p-.76), but not for any of the single sleep stages within NonREM sleep (S1, S2, S3, S4, and SWS). REM sleep, in contrast to NonREM sleep, was negatively corre- lated with memory accuracy, although not significantly (r--.53, p-.116) and tended to be associated with higher overall false alarm rates (r-.59, p .072) Regarding reaction times, there was a strong negative correlation between REM sleep and reaction times for old 042, happy face r-.61, p-.063, neutral faces: s: faces (r--.76, p-.012), but not for new faces (r--.02, p .95). Consequently, REM sleep was also associated with the difference between old and new faces in reaction times as an indicator of implicit memory (r--.70, p-.024; Fig. 2b). This pattern was observed in all three valence cate- gories, but did not reach significance in separate analyse:s for the three categories (angry: -0.54, p-.108. happy: 0.54, p-,108, neutral:-0.59, p-071). Neither NonREM sleep overall nor any sub-stage of NonREM sleep correlated significantly with any reaction time measure.

For the first correlation reported in the results section 3.3:

1. Is the correlation statistically significant?

Also whats the importance of this study? Thank you!

Answer 1

This is a simple problem related to making an inference about the significance of the memory to hte kind of sleep on a given level of confidence.

Clealry if we take the first corrleation case ,we can see that all the correlations between memory and the REM sleep types is siginificant at 90% confidence interval.

i.e, we can say that there exisits a very strong correlation between memory and REM sleep type with a 90 % confidence

But why did we choose the 90 % confidence interval and not 95 5 or 99 %?

This is so because the section 3.3 says that all the given correlations are siginificiant eith a given values whilch are <0.10 (which is the borderline cut off limit for 90% confidence limit.

Thus if we check for the correlations between all the given factors in 3.3 we will get the following which gives us a complete picture of correlation significance between variaous variables with each other.

	Correlation between					a(alpha)
S.No.	Memory accurancy	Sleep type	Correlation	Inference	p value	p value <a?	Inference
1	Memory accuracy	NonREM Sleep	0.79	Positive correaltion. As one inceases other also incereaes	0.07	yes	The correlation is siginificant with 90 % conifdence
2	hit rate	NonREM Sleep	0.36	Positive correaltion. As one inceases other also incereaes	0.31	No	The correlation is NOT siginificant with 90 % conifdence
3	false alarm	NonREM Sleep	-0.42	Negative correlation as one variable increases other decreases	0.23	No	The correlation is NOT siginificant with 90 % conifdence
4	Memory accuracy when angry	NonREM Sleep	0.79	Positive correaltion. As one inceases other also incereaes	0.006	yes	The correlation is siginificant with 90 % conifdence
5	Memory accuracy when happy	NonREM Sleep	0.86	Positive correaltion. As one inceases other also incereaes	0.001	yes	The correlation is siginificant with 90 % conifdence
6	Memory accuracy when neutral	NonREM Sleep	0.03	Positive correaltion. As one inceases other also incereaes	0.93	No	The correlation is NOT siginificant with 90 % conifdence
7	Memory accuracy when angry after learning	NonREM Sleep	0.66	Positive correaltion. As one inceases other also incereaes	0.037	yes	The correlation is siginificant with 90 % conifdence
8	Memory accuracy when happy after learning	NonREM Sleep	0.61	Positive correaltion. As one inceases other also incereaes	0.063	yes	The correlation is siginificant with 90 % conifdence
9	Memory accuracy when neutral after learning	NonREM Sleep	0.11	Positive correaltion. As one inceases other also incereaes	0.76	No	The correlation is NOT siginificant with 90 % conifdence
10	Memory accuracy after learning	NonREM Sleep	0.65	Positive correaltion. As one inceases other also incereaes	0.042	yes	The correlation is siginificant with 90 % conifdence
11	Memory accuracy	REM sleep	-0.53	Negative correlation as one variable increases other decreases	0.116	No	The correlation is NOT siginificant with 90 % conifdence
12	Memory accuracy when False alarm	REM sleep	0.59	Positive correaltion. As one inceases other also incereaes	0.072	yes	The correlation is siginificant with 90 % conifdence
13	Reaction time of old faces	REM sleep	-0.76	Negative correlation as one variable increases other decreases	0.012	yes	The correlation is siginificant with 90 % conifdence
14	Reaction time of freash faces	REM sleep	-0.02	Negative correlation as one variable increases other decreases	0.95	No	The correlation is NOT siginificant with 90 % conifdence
15	Implicite memory	REM sleep	-0.7	Negative correlation as one variable increases other decreases	0.024	yes	The correlation is siginificant with 90 % conifdence
16	Implicite memory when angry	REM sleep	-0.54	Negative correlation as one variable increases other decreases	0.108	No	The correlation is NOT siginificant with 90 % conifdence
17	Implicite memory when happy	REM sleep	-0.54	Negative correlation as one variable increases other decreases	0.108	No	The correlation is NOT siginificant with 90 % conifdence
	Implicite memory when neutral	REM sleep	-0.59	Negative correlation as one variable increases other decreases	0.071	yes	The correlation is siginificant with 90 % conifdence