Acute psychosocial stress and children’s memory

Figures & data

Figure 1. Overview of the procedures for the control condition (top), and the stress condition (bottom). Intro = introduction; Sq = short questionnaire; Qs = questionnaires; C = control condition saliva sample; S = stress condition saliva sample. The shaded areas in the stress condition indicate the presence of the TSST-C jury.

Table 1. Raw cortisol and sAA levels for the stress condition.

	Raw cortisol		Raw sAA
	n	Md (IQR)	n	Md (IQR)
S1	158	6.80 (5.60–8.40)	156	166.75 (92.00–257.13)
S2	158	5.30 (4.40–6.20)	157	107.50 (75.50–166.50)
S3	158	6.35 (5.20–8.20)	157	171.00 (108.25–311.75)
S4	158	7.30 (5.68–10.80)	157	204.50 (120.50–336.00)
S5	158	7.65 (5.38–11.13)	158	179.50 (109.88–297.88)
S6	158	6.80 (4.95–9.30)	158	141.75 (88.13–226.00)
S7	158	5.90 (4.30–7.43)	158	128.75 (80.75–203.88)

Table 2. Descriptives and correlations for the study variables.

		Descriptives M (SD) or Md (IQR)	Correlations
			1	2	3	4	5	6	7	8	9	10
1.	Delta cortisol	1.10 (−0.10 to 2.70)
2.	Delta sAA^a	57.5 (11.25–154.00)	0.13
3.	WM fw control	8.00 (7.00–9.00)	−0.05	−0.20*
4.	WM fw stress	5.00 (4.00–6.00)	0.14^+	−0.11	0.64**
5.	WM bw control	8.00 (7.00–9.00)	0.04	−0.06	0.35**	0.36**
6.	WM bw stress	5.00 (4.00–6.00)	0.02	−0.03	0.40**	0.43**	0.50**
7.	DR control	3.51 (1.50)	−0.05	0.11	0.10	0.06	0.00	0.12
8.	DR stress	3.25 (1.49)	0.00	0.07	0.07	−0.02	0.08	0.13	0.29**
9.	Age	10.61 (0.52)	−0.04	0.02	0.03	0.10	0.16*	0.17*	−0.04	0.00
10.	Parental education	7.00 (5.50–7.50)	−0.07	0.00	0.00	−0.09	−0.06	−0.29**	−0.11	−0.10	0.10
11.	Pubertal stage	2.00 (1.50–2.50)	−0.04	−0.05	0.09	0.02	0.12	−0.04	0.03	0.01	0.27**	0.09

^aN = 156, for all other variables N = 158.

⁺p < 0.10. *p < 0.05. **p ≤ 0.01.

Figure 2. Increases in cortisol (left panel) and sAA (right panel) over time for the control and stress conditions. Plots display means and standard errors of raw data; statistical analyses were performed with log-transformed data for cortisol and sqrt-transformed data for sAA.

Table 3. Final regression models for the prediction of WM forward and DR in the stress condition.

	B	SE	β	R²model	Fchange	R²change
WM forward^a				0.41	109.54**
Step 1
WM forward control	0.64	0.06	0.65**
Step 2				0.44	8.29**	0.03
Cortisol reactivity	0.26	0.09	0.17**
Delayed retrieval^b				0.10	8.59**
Step 1
DR control	0.32	0.08	0.32**
Sex^c	−0.39	0.23	−0.13
Step 2				0.15	2.17^+	0.05
sAA reactivity	0.01	0.03	0.03
Cortisol reactivity	−0.03	0.63	0.00
Cortisol reactivity × cortisol reactivity	−3.77	1.87	−0.15*
Cortisol reactivity × sAA reactivity	0.37	0.17	0.17*

^aInitial model for WM forward (sqrt): step 1 – WM forward control (sqrt), sex, age, parental education level (log10), puberty (sqrt); step 2 – sAA reactivity (sqrt), cortisol reactivity (log10), sAA reactivity × sAA reactivity, cortisol reactivity × cortisol reactivity, cortisol reactivity × sAA reactivity. ^bInitial model for DR: step 1 – DR control, immediate recall, time between encoding and retrieval (log10), age, parental education level (log10), puberty (sqrt); step 2 – sAA reactivity (sqrt), cortisol reactivity (log10), sAA reactivity × sAA reactivity, cortisol reactivity × cortisol reactivity, cortisol reactivity × sAA reactivity. ^cGirls = 0, Boys = 1

⁺p < 0.10. *p < 0.05. **p < 0.01.

Figure 3. The relation between stress condition cortisol responses and delayed retrieval memory performance. There was a significant quadratic relation (left panel), as well as a significant interaction between sAA and cortisol (right panel). Note: average DR memory performance in the control condition was 3.5.