Exploring neuropsychological underpinnings of poor communication after traumatic brain injury: The role of apathy, disinhibition and social cognition.

Background: Dysarthria, aphasia and executive processes have been examined for their role in producing impaired communicative competence post traumatic brain injury (TBI). Less understood is the role of emotional dysregulation, that is, apathy and disinhibition, and social cognition, that is, reading and interpreting social cues.

Methods & Procedures: In this study, we examined 49 adults with moderate to severe TBI and 18 neurologically healthy adults. We hypothesised that apathy and disinhibition would predict communication outcomes as would social cognition. We also predicted that apathy and disinhibition would influence social cognition. Communication outcomes were measured by the La Trobe Communication Questionnaire (LCQ) and the Social Skills Questionnaire-TBI (SSQ-TBI). Apathy and disinhibition were measured by the Frontal Systems Behavior Scale (FrSBe). We measured four aspects of social cognition: emotion perception and theory of mind using The Awareness of Social Inference Test (TASIT) and the Complex Audio-Visual Evaluation of Affect Test (CAVEAT), empathy using the Questionnaire of Cognitive and Affective Empathy (QCAE) and the Balanced Emotional Empathy Scale (BEES), and alexithymia using the Toronto Alexithymia Scale (TAS-20) and the Bermond-Vorst Alexithymia Questionnaire.

Outcomes & Results: Consistent with predictions, the LCQ and SSQ-TBI were associated with disinhibition and the LCQ was also associated with apathy. The LCQ was associated with the full range of social cognition constructs although the SSQ-TBI was not. Finally, apathy and disinhibition predicted a number of social cognition measures.

Conclusions And Implications: These results are discussed in relation to understanding the nature of communication disorders following TBI and how they are measured, as well as the interrelation between emotion dysregulation and social cognition.

What This Study Adds: What is already known on this subject The role of emotional dysregulation and social cognition in producing impaired communicative competence post traumatic brain injury (TBI) is not well understood. Although most adults with severe TBI have minimal or possibly no language impairment, they often struggle with functional communication in everyday situations. Many have been reported to be overtalkative, insensitive, childish and self-centred, displaying an inappropriate level of self-disclosure and making tangential and irrelevant comments. Conversely, some speakers with TBI have been noted to have impoverished communication, producing little language either spontaneously or in response to the speaker's questions and prompts. What this paper adds to existing knowledge We found that both apathy and disinhibition were strongly associated with the Latrobe Communication Questionnaire both empirically and conceptually, despite the LCQ being developed from a different, pragmatic orientation. Disinhibition was also associated with the Social Skills Questionnaire for TBI. We also found that poor social cognition scores predicted communication difficulties. Finally, we found that behavioural dysregulation itself, i.e., both apathy and disinhibition, predicted poor social cognition. What are the potential or actual clinical implications of this work? Our findings highlight the central role that apathy and disinhibition play in both communication and social cognition. These insights point to the importance of remediation to target behavioural and autonomic dysregulation as a means to improve everyday social function.