Diurnal Cortisol Dynamics, Perceived Stress, and Language Production in Aphasia.

Area of Science:

• Neuroscience
• Psychology
• Speech and Language Pathology

Background:

• Cortisol, a biomarker for stress, is linked to cognitive issues in various groups.
• Stress-induced cortisol disturbances in stroke survivors, particularly those with aphasia, are understudied.
• The hypothalamic-pituitary-adrenal (HPA) axis regulates cortisol release.

Purpose of the Study:

• Investigate diurnal cortisol dynamics in adults with and without aphasia.
• Examine stress levels and language production in relation to cortisol.
• Determine the link between HPA axis function and language performance.

Main Methods:

• Recruited 19 adults with aphasia and 14 neurotypical adults.
• Collected saliva samples to measure the cortisol awakening response (CAR).
• Administered stress questionnaires and analyzed language narratives for fluency and productivity.

Main Results:

• Adults with aphasia showed an absent CAR and heightened cortisol upon awakening, unlike neurotypical controls.
• Neurotypical participants displayed a correlation between intact language and CAR.
• Participants with aphasia did not show this association, despite reporting stress from language tasks.

Conclusions:

• HPA axis functionality, indicated by cortisol, supports optimal language performance in healthy adults.
• The absence of CAR in aphasia suggests HPA axis dysregulation following stroke.
• Further research is needed to clarify the impact of HPA axis impairment on aphasia deficits.