Outcome Evaluation in Social Context Measured by Event-Related Potentials Is Partially Dependent on the Partner’s Sex

Abstract Natural use of language involves at least two individuals. Some studies have focused on the interaction between senders in communicative situations and how the knowledge about the speaker can bias language comprehension. However, the mere effect of a face as a social context on language processing remains unknown. In the present study, we used event-related potentials to investigate the semantic and morphosyntactic processing of speech in the presence of a photographic portrait of the speaker. In Experiment 1, we show that the N400, a component related to semantic comprehension, increased its amplitude when processed within this minimal social context compared to a scrambled face control condition. Hence, the semantic neural processing of speech is sensitive to the concomitant perception of a picture of the speaker’s face, even if irrelevant to the content of the sentences. Moreover, a late posterior negativity effect was found to the presentation of the speaker’s face compared to control stimuli. In contrast, in Experiment 2, we found that morphosyntactic processing, as reflected in left anterior negativity and P600 effects, is not notably affected by the presence of the speaker’s portrait. Overall, the present findings suggest that the mere presence of the speaker’s image seems to trigger a minimal communicative context, increasing processing resources for language comprehension at the semantic level.

Download Full-text

Task instructions: a part of the social context of participants? A N300 and N400 event-related brain potential study

10.31234/osf.io/u9xfv ◽

2020 ◽

Author(s):

Sujata Sinha ◽

Sheila Bouten ◽

Amanda Tardif ◽

Tarlan Daryoush ◽

Natalie Frye ◽

...

Keyword(s):

Social Context ◽

Everyday Life ◽

Event Related Potentials ◽

Social Contexts ◽

Cognitive Behaviors ◽

Task Instructions ◽

The Social ◽

Related Potentials ◽

Mere Presence ◽

Motor Representations

The early and preconscious processing of stimuli that are meaningful in everyday life includes systematical activations of many semantic, emotional and motor representations. Inhibitions should then occur in order to select, among these primed representations, those that are consistent with the context. Even in a lab this context is social, as it typically consists of the experimenter and of the instructions and stimuli (s)he provides. Three recent N400 studies confirm this social view of experimental settings by showing that socially driven processes affect what was primed by prior stimuli. The small amplitudes of the N400 event-related potentials (ERPs) elicited by stimuli preceded by semantical primes were found to be enhanced by the mere presence of a person next to participants when they know this person did not have the semantic primes. It thus seems that N400 processes inhibit what these primes have activated so that participants can also have the perspective of the uninformed person. This inhibition interpretation implies that N400s should be notably reduced when nothing allows to determine what should be inhibited, that is, when the social context is not defined and when task’s instructions require minimal inhibition. We tested this prediction by having a stranger next to participants (n=29) and by presenting meaningful unpredictable images in a simple memorization task. As foreseen, N400s were small. They were enhanced by definable social contexts, that is, in participants alone with the experimenter (n=30) and in those with a friend (n = 36). The amplitudes of the N300s were also enhanced. A second experiment revealed that these N300 and N400 enhancements were larger for friends who felt in the presence of their partner during most of the experiment. As to the late posterior positivities (LPPs) immediately succeeding the N400s, they were found to be larger in the unknown social context of the first experiment, suggesting that more information ended up being placed into the working memory when inhibitions could not occur. These results are compatible with a serial 3-stages framework of the processing of stimuli meaningful in everyday life. Early and broad systematic activations (priming) would be followed by automatic late selections done according to the social-context and then, by the participant’s consciousness of the meanings of the stimulus in this context. As inadequate late selections would cause impairments of social and cognitive behaviors, the present results could have implications for psychiatric disorders, such as autism and schizophrenia.

Download Full-text

Theta-Burst Stimulation Is Able to Impact Cognitive Processing: A P300 and Neuropsychological Test Study

Neuropsychobiology ◽

10.1159/000511605 ◽

2021 ◽

pp. 1-11

Author(s):

Nuno Filipe Cardoso Pinto ◽

Marta Duarte ◽

Helena Gonçalves ◽

Ricardo Silva ◽

Jorge Gama ◽

...

Keyword(s):

Neuropsychological Tests ◽

Group Performance ◽

Event Related Potentials ◽

Outcome Evaluation ◽

Controlled Study ◽

Oddball Paradigm ◽

Theta Burst Stimulation ◽

Burst Stimulation ◽

Related Potentials ◽

Theta Burst

Introduction: Theta-burst stimulation (TBS) is a safe non-invasive neurostimulation technique used to improve cognitive and neuropsychiatric impairments. Combined outcome evaluation using event-related potentials (ERPs) and neuropsychological tests may allow a more thorough assessment of TBS treatment efficacy; however, some mixed results have been found, and their use remains scarce. Our main objective was to evaluate whether a session of TBS to the left dorsolateral prefrontal cortex (DLPFC) can impact upon the performance of both neuropsychological and neurophysiological tests. Methods: This double-blind sham-controlled study involved 28 healthy adults, between 18 and 30 years. Volunteers were randomly allocated to receive excitatory (intermittent [iTBS]), inhibitory (continuous TBS [cTBS]) or sham stimulation on the left DLPFC. Subjects were evaluated using ERPs (auditory oddball paradigm P300) and neuropsychological tests (Trail making test [TMT] and Stroop test of words and colours [STWC]), using a pre-post stimulation protocol. Results: Inhibitory stimulation led to significantly delayed P300 peak latencies (p < 0.001), with no consistent change in N2P3 amplitudes. cTBS also significantly influenced the expected group performance in Stroop C and Stroop interference (p = 0.025) compared to the iTBS and sham groups. No significant results were found in TMT tests after TBS. Conclusion: Our results suggest that P300 and specific Stroop colour and words test parameters can be similarly influenced by the same TBS protocol. This emphasizes the importance of mixed evaluation using neuropsychological and neurophysiological resources in research associated with the use of transcranial magnetic stimulation and cognition.

Download Full-text