Perceived control moderates the impact of academic stress on the attention process of working memory in male college students

Figures & data

Table 1. Descriptive statistics and bivariate correlations among study variables (N = 59).

Variable	Mean	Standard deviation	1	2	3	4	5	6	7	8	9	10	11
1. Academic Stress	26.15	6.87	—
2. Perceived Control	61.58	9.01	−.194	—
3. Neuroticism	2.72	0.6	.326*	−.791**	—
4. Age	22.07	2.14	−.113	.260*	−.147	—
5. 2-back ACC	0.92	0.05	−.261*	.123	−.115	−.129	—
6. 2-back RT (ms)	775	158	−.027	−.085	.081	−.066	−.056	—
7. 3-back ACC	0.78	0.08	−.110	.204	−.129	−.185	.672**	.018	—
8. 3-back RT (ms)	860	162	−.125	.106	−.042	.193	.054	.472**	−.047	—
9. 2-back P2 (μV)	4.79	4.23	−.160	.198	−.031	.260*	.093	−.253	.110	−.209	—
10. 3-back P2 (μV)	4.36	4.03	−.225^+	.279*	−.159	.157	.274*	−.181	.242	−.176	.849**	—
11. 2-back P3 (μV)	3.94	4.00	−.072	−.064	.133	−.271*	.027	−.256	.084	.027	.159	.143	—
12. 3-back P3 (μV)	3.25	3.09	.083	−.110	.128	−.374**	.126	−.045	.324*	−.144	.004	.084	.703**

The values presented here are not mean centered.

⁺p < 0.1, *p < 0.05, **p < 0.01.

Figure 1 Stimulus-locked grand average ERP amplitude (uV) in function of time (milliseconds) elicited during the 2-back (black line) and 3-back (red-orange line) conditions. The topographies are the comparisons of the scalp distribution of the fronto-central P2 (160–190 ms) and the posterior P3 (300–450 ms) between 2-back and 3-back conditions.

Table 2. Results of multiple regression analyses predicting P2 amplitudes at 3-back.

		P2 amplitudes at 3-back
	Variable	B	SE	β	B	SE	β	B	SE	β
Step 1	Age	0.258	0.249	0.137	0.108	0.254	0.058	0.154	0.247	0.082
	Neuroticism	−0.939	0.892	−0.139	1.475	1.463	0.218	1.672	1.421	0.248
Step 2	Academic stress				−2.378	1.951	−0.168	−2.823	1.902	−0.199
	Perceived control				10.386	5.509	0.403^+	10.836	5.344	0.421*
Step 3	Academic stress × Perceived Control							29.872	14.117	0.266*
R^2		0.044			0.116			0.185
△R^2		0.044			0.072			0.069
Model F		F (2, 56) = 1.276			F (4, 54) = 1.773			F (5, 53) = 2.405*

The scores of perceived control and academic stress were log-transformed because of non-normal distributions. Then all independent variables were mean centered before model estimation.

⁺p < 0.1, *p < 0.05, **p < 0.01.

Figure 2 Visual depiction of the interaction between academic stress and perceived control. SD = standard deviation. We computed predicted values of the P2 amplitudes at 3-back for three groups: (1) 1 standard deviation below the mean of perceived control; (2) the mean of perceived control; (3) 1 standard above the mean of perceived control. The simple slope test showed that only for students reported low level of perceived control, there was a significant negative effect of academic stress on P2 amplitudes at 3-back (m = −7.5, p =.018).