Research Reports - Impaired perception of sincerity after traumatic brain injury
J Neuropsychol. 2015 Oct 19. doi: 10.1111/jnp.12086. [Epub ahead of print]
McDonald S(1), Fisher A(1), Flanagan S(1), Honan CA(1).
BACKGROUND: People with a severe traumatic brain injury (TBI) often experience
problems understanding non-literal utterances such as sarcasm and lies in dyadic
exchanges. This study aimed to investigate whether these problems extend to
settings where speakers vary in their degree of sincerity and whether such
problems are associated with deficits in social cognitive abilities (emotion
perception, theory of mind, and self-reported empathy) or cognitive abilities
(abstract reasoning, working memory, processing speed, attentional switching).
METHODS: Thirty-one adults with severe TBI (24 males) and 25 demographically
matched controls (20 males) participated. They watched video vignettes depicting
four actors volunteering for additional duties. Each speaker made a limited
verbal response which literally suggested a willingness to be involved, but the
sincerity with which the response was made was tempered by the actor's emotional
demeanour. Participants rated each speaker in the vignettes for degree of
sincerity (0-100%). Standardized measures of cognitive and social cognitive
function were also taken.
RESULTS: Control participants had excellent agreement (α = .90) in their rankings
of actors according to sincerity. TBI participants were less consistent
(α = .65). Overall, they were sensitive to decreasing sincerity but generally
less accurate than control participants. They were poorer at differentiating
between levels of sincerity and rated insincere expressions as more sincere,
although they rated sincere expressions similarly. Poorer working memory and
poorer social cognition were associated with poorer sincerity/sarcasm detection
in the participants with TBI, but only social cognition was uniquely associated.
CONCLUSIONS: Some adults with TBI have difficulty assessing the level of
sincerity of speakers. Moreover, poorer social cognition abilities are associated
with this difficulty.