Research Reports - Affect recognition, empathy and dysosmia following traumatic brain injury
Neumann D, Zupan B, Babbage D, Radnovich A, Tomita M, Hammond F, Willer B.
Arch Phys Med Rehabil. 2012 Mar 2
OBJECTIVE: To investigate if olfaction is associated with affect recognition and empathy deficits after Traumatic Brain Injury (TBI). Prior research has shown that TBI often leads to loss of smell. We hypothesized a relationship with emotion perception because the neural substrates of the olfactory system overlap with the ventral circuitry of the orbital frontal cortex, which play a critical role in affective responses such as empathy. DESIGN: Comparative study investigating differences between participants with TBI who had impaired olfaction (dysosmia) to those with normal olfaction (normosmia). SETTING:
Post-acute rehabilitation facilities in the United States, Canada, and New Zealand. PARTICIPANTS: Participants in the current study were a convenience sample of 106 adults with moderate to severe TBI who were tested for olfactory function as part of a larger, related study on affect recognition. On average, participants were 11.5 years post-injury. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Olfaction (BSIT); facial affect recognition (DANVA2-Adult Faces; AF); vocal affect recognition (DANVA2-Adult Paralanguage; AP); emotional inference (EIST); and empathy (IRI). RESULTS: 56% participants were dysosmic and only 36% of these participants were aware of their deficit. Participants with dysosmia performed significantly poorer on the DANVA-AF (p=.003), DANVA-AP (p=.007), EIST (p=.016), and IRI (p=.0125). Medium effect sizes were found for
all measures. Dysosmia had a sensitivity value of 86.4% for detecting facial affect recognition impairments and 67.8 % for vocal affect recognition impairments. CONCLUSION: This study shows that olfactory deficits may be indicative of affect recognition impairments and reduced empathy. Early knowledge of affect recognition and empathy deficits would be valuable so that treatment could be implemented pre-discharge.