Limits...
Acute Stress Dysregulates the LPP ERP Response to Emotional Pictures and Impairs Sustained Attention: Time-Sensitive Effects.

Alomari RA, Fernandez M, Banks JB, Acosta J, Tartar JL - Brain Sci (2015)

Bottom Line: We found that the effects of stress on the LPP ERP emotion measure were time sensitive.Moreover, compared to the non-stress condition, the stress-condition showed impaired performance on the SART.Our results support the idea that a limit in attention resources after an emotional stressor is associated with the brain incorrectly processing non-emotional stimuli as emotional and interferes with sustained attention.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology and Neuroscience, Nova Southeastern University, Ft. Lauderdale, FL 33314, USA. ra714@nova.edu.

ABSTRACT
Stress can increase emotional vigilance at the cost of a decrease in attention towards non-emotional stimuli. However, the time-dependent effects of acute stress on emotion processing are uncertain. We tested the effects of acute stress on subsequent emotion processing up to 40 min following an acute stressor. Our measure of emotion processing was the late positive potential (LPP) component of the visual event-related potential (ERP), and our measure of non-emotional attention was the sustained attention to response task (SART). We also measured cortisol levels before and after the socially evaluated cold pressor test (SECPT) induction. We found that the effects of stress on the LPP ERP emotion measure were time sensitive. Specifically, the LPP ERP was only altered in the late time-point (30-40 min post-stress) when cortisol was at its highest level. Here, the LPP no longer discriminated between the emotional and non-emotional picture categories, most likely because neutral pictures were perceived as emotional. Moreover, compared to the non-stress condition, the stress-condition showed impaired performance on the SART. Our results support the idea that a limit in attention resources after an emotional stressor is associated with the brain incorrectly processing non-emotional stimuli as emotional and interferes with sustained attention.

No MeSH data available.


Related in: MedlinePlus

LPP ERP. The LPP ERP elicited by the IAPS in the control and stress conditions during each Block at each electrode location. In Blocks 1 and 2 (3A) and (3B), there were no differences in the LPP amplitude between the stress and the control conditions. However, in Block 3 (3C), the neutral pictures elicited a larger LPP in the stress condition relative to the control condition during Block 3. Black horizontal bar in Cz indicates the 400 ms picture exposure and the yellow horizontal bar indicates the LPP analysis latency range.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4493465&req=5

brainsci-05-00201-f003: LPP ERP. The LPP ERP elicited by the IAPS in the control and stress conditions during each Block at each electrode location. In Blocks 1 and 2 (3A) and (3B), there were no differences in the LPP amplitude between the stress and the control conditions. However, in Block 3 (3C), the neutral pictures elicited a larger LPP in the stress condition relative to the control condition during Block 3. Black horizontal bar in Cz indicates the 400 ms picture exposure and the yellow horizontal bar indicates the LPP analysis latency range.

Mentions: Figure 3 presents the grand average visual ERPs separated by time and picture category, for all electrode locations. We analyzed the visual LPP using a 3 (time) × 3 (picture category) × 7 (electrode location) mixed-model ANOVA with condition (stress vs. control) as the between subjects factor. As expected and consistent with previous studies, this analysis revealed a significant main effect for picture category (F (2, 68) = 29.67, p < 0.001, partial η2 = 0.49); the LPP responses to negative (M = 4.66, SE = 0.65) and positive pictures (M = 3.84, SE = 065) were larger than to neutral pictures (M = 0.24, SE = 0.71). There was also a significant main effect for electrode location (F (6204) = 13.06, p < 0.001, partial η2 = 0.30), but no main effect of condition, p > 0.05. The interaction analyses showed a significant time x electrode interaction (F (12,408) = 2.52, p < 0.01, partial η2 = 0.08) and significant picture × electrode interaction (F (12,408) = 11.60, p < 0.001, partial η2 = 0.27, but no time × condition interaction (F (2, 62) = 0.33, p = 0.72). Although we did not observe a significant effect of condition or a time × condition interaction, we did observe time × electrode and picture × electrode interactions. To test our a priori hypothesis that the effects of stress on LPP would be altered at the latest post-stress time-point (30–40 min post stress induction), a series of exploratory planned one-way ANOVA were conducted separately at each time-point in order to observe the effects of condition (stress vs. control) at each electrode location and for each picture category. This analysis confirmed the visual observation and our expectation that the LPP differentiated between emotional and non-emotional pictures in both the stress and the control condition early on after stress induction (i.e., in Block 1 and 2), such that LPP amplitude for neutral pictures (Block 1, M = −0.51, SE = 1.09; Block 2, M = 0.18, SE = 0.83) was lower than negative (Block 1, M = 3.45, SE = 0.86; p < 0.01 ; Block 2, M = 4.41, SE = 1.05; p < 0.05) and positive pictures (Block 1, M = 4.02, SE = 0.91l p < 0.05; Block 2, M = 5.21, SE = 0.94; p < 0.01). No differences were found between the two condition for LPP response to emotional pictures (positive or negative) in Block 3, all p’s >0.05. However, as predicted, later stress effects (at Block 3) dysregulated the LPP response, such that there was not a significant effect of picture for the stress condition, p > 0.05. Specifically, the LPP for the neutral pictures were significantly larger in the stress condition compared to the control condition at Fz (control M = −2.82, SD = 6.49; stress M = 1.87, SD = 6.17; p < 0.05), Cz (control M = −0.22, SD = 5.25; stress M = 4.01, SD = 4.99; p < 0.05), and O1 (control M = −0.30, SD = 3.68; stress M = 2.63, SD = 4.24; p < 0.05) electrode locations. However, the LPP amplitude for the control condition was similar to response seen in Blocks 1 and 2, with neutral pictures showing a smaller LPP amplitude (M = −0.55, SE = 1.67) than negative (M = 3.45, SE = 1.37; p < 0.05) or positive pictures (M = 3.82, SE = 1.14; p < 0.05).


Acute Stress Dysregulates the LPP ERP Response to Emotional Pictures and Impairs Sustained Attention: Time-Sensitive Effects.

Alomari RA, Fernandez M, Banks JB, Acosta J, Tartar JL - Brain Sci (2015)

LPP ERP. The LPP ERP elicited by the IAPS in the control and stress conditions during each Block at each electrode location. In Blocks 1 and 2 (3A) and (3B), there were no differences in the LPP amplitude between the stress and the control conditions. However, in Block 3 (3C), the neutral pictures elicited a larger LPP in the stress condition relative to the control condition during Block 3. Black horizontal bar in Cz indicates the 400 ms picture exposure and the yellow horizontal bar indicates the LPP analysis latency range.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493465&req=5

brainsci-05-00201-f003: LPP ERP. The LPP ERP elicited by the IAPS in the control and stress conditions during each Block at each electrode location. In Blocks 1 and 2 (3A) and (3B), there were no differences in the LPP amplitude between the stress and the control conditions. However, in Block 3 (3C), the neutral pictures elicited a larger LPP in the stress condition relative to the control condition during Block 3. Black horizontal bar in Cz indicates the 400 ms picture exposure and the yellow horizontal bar indicates the LPP analysis latency range.
Mentions: Figure 3 presents the grand average visual ERPs separated by time and picture category, for all electrode locations. We analyzed the visual LPP using a 3 (time) × 3 (picture category) × 7 (electrode location) mixed-model ANOVA with condition (stress vs. control) as the between subjects factor. As expected and consistent with previous studies, this analysis revealed a significant main effect for picture category (F (2, 68) = 29.67, p < 0.001, partial η2 = 0.49); the LPP responses to negative (M = 4.66, SE = 0.65) and positive pictures (M = 3.84, SE = 065) were larger than to neutral pictures (M = 0.24, SE = 0.71). There was also a significant main effect for electrode location (F (6204) = 13.06, p < 0.001, partial η2 = 0.30), but no main effect of condition, p > 0.05. The interaction analyses showed a significant time x electrode interaction (F (12,408) = 2.52, p < 0.01, partial η2 = 0.08) and significant picture × electrode interaction (F (12,408) = 11.60, p < 0.001, partial η2 = 0.27, but no time × condition interaction (F (2, 62) = 0.33, p = 0.72). Although we did not observe a significant effect of condition or a time × condition interaction, we did observe time × electrode and picture × electrode interactions. To test our a priori hypothesis that the effects of stress on LPP would be altered at the latest post-stress time-point (30–40 min post stress induction), a series of exploratory planned one-way ANOVA were conducted separately at each time-point in order to observe the effects of condition (stress vs. control) at each electrode location and for each picture category. This analysis confirmed the visual observation and our expectation that the LPP differentiated between emotional and non-emotional pictures in both the stress and the control condition early on after stress induction (i.e., in Block 1 and 2), such that LPP amplitude for neutral pictures (Block 1, M = −0.51, SE = 1.09; Block 2, M = 0.18, SE = 0.83) was lower than negative (Block 1, M = 3.45, SE = 0.86; p < 0.01 ; Block 2, M = 4.41, SE = 1.05; p < 0.05) and positive pictures (Block 1, M = 4.02, SE = 0.91l p < 0.05; Block 2, M = 5.21, SE = 0.94; p < 0.01). No differences were found between the two condition for LPP response to emotional pictures (positive or negative) in Block 3, all p’s >0.05. However, as predicted, later stress effects (at Block 3) dysregulated the LPP response, such that there was not a significant effect of picture for the stress condition, p > 0.05. Specifically, the LPP for the neutral pictures were significantly larger in the stress condition compared to the control condition at Fz (control M = −2.82, SD = 6.49; stress M = 1.87, SD = 6.17; p < 0.05), Cz (control M = −0.22, SD = 5.25; stress M = 4.01, SD = 4.99; p < 0.05), and O1 (control M = −0.30, SD = 3.68; stress M = 2.63, SD = 4.24; p < 0.05) electrode locations. However, the LPP amplitude for the control condition was similar to response seen in Blocks 1 and 2, with neutral pictures showing a smaller LPP amplitude (M = −0.55, SE = 1.67) than negative (M = 3.45, SE = 1.37; p < 0.05) or positive pictures (M = 3.82, SE = 1.14; p < 0.05).

Bottom Line: We found that the effects of stress on the LPP ERP emotion measure were time sensitive.Moreover, compared to the non-stress condition, the stress-condition showed impaired performance on the SART.Our results support the idea that a limit in attention resources after an emotional stressor is associated with the brain incorrectly processing non-emotional stimuli as emotional and interferes with sustained attention.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology and Neuroscience, Nova Southeastern University, Ft. Lauderdale, FL 33314, USA. ra714@nova.edu.

ABSTRACT
Stress can increase emotional vigilance at the cost of a decrease in attention towards non-emotional stimuli. However, the time-dependent effects of acute stress on emotion processing are uncertain. We tested the effects of acute stress on subsequent emotion processing up to 40 min following an acute stressor. Our measure of emotion processing was the late positive potential (LPP) component of the visual event-related potential (ERP), and our measure of non-emotional attention was the sustained attention to response task (SART). We also measured cortisol levels before and after the socially evaluated cold pressor test (SECPT) induction. We found that the effects of stress on the LPP ERP emotion measure were time sensitive. Specifically, the LPP ERP was only altered in the late time-point (30-40 min post-stress) when cortisol was at its highest level. Here, the LPP no longer discriminated between the emotional and non-emotional picture categories, most likely because neutral pictures were perceived as emotional. Moreover, compared to the non-stress condition, the stress-condition showed impaired performance on the SART. Our results support the idea that a limit in attention resources after an emotional stressor is associated with the brain incorrectly processing non-emotional stimuli as emotional and interferes with sustained attention.

No MeSH data available.


Related in: MedlinePlus