Characterizing the Neural Profile of Auditory Hallucinations in Bipolar Disorder

Bipolar disorder (BD) is a psychiatric condition affecting 1% of Canadians with up to 40% of those diagnosed experiencing auditory hallucinations (AH) during their illness. While hallucinations are well studied in other psychiatric disorders like schizophrenia (SZ), the impact they have on those with BP is understudied. The limited work that exists leads us to believe that AHs experienced by those with BP differ from those experienced in SZ; one commonality between diagnoses is that experiencing AH predicts a worse quality of life and an increased risk of suicide. The proposed study aims to understand how AHs impact the neural functioning and quality of life of those with BP. The proposed project will examine brain activity in individuals with BP and AHs, individuals with BP and no AHs, and unaffected controls. To assess neural functioning, we will examine a brainwave called the mismatch negativity (MMN); while the MMN represents the brain sub-consciously detecting changes in the sound environment because it occurs so quickly and automatically it has been used to assess how well the brains auditory system is functioning. There are robust findings of reductions in the MMN reported in those with schizophrenia, especially individuals experiencing hallucinations. We anticipate that if these neural networks are different across disorders, we will see differences in MMN amplitude in participants with BP and AH that are different from what is shown in SZ. Finally, we will collect information on how AHs impact the quality of life of those affected. This study will address a critical gap in the literature and aims to characterize the brain-based features of auditory hallucinations in BP and explore their impact on daily functioning and quality of life. Insights from this study could help inform tailored therapeutic interventions and improve the lives of those with BP in Canada.