Functional Connectivity and Predictors of Affective Aprosodia Intervention in Subacute Right Hemisphere Stroke

Functional Connectivity and Predictors of Affective Aprosodia Intervention in Subacute Right Hemisphere Stroke

This study is an investigation of a behavioral speech and language treatment for emotional prosody recognition and production deficits in subacute right hemisphere stroke.

The phrase, "it's not what you say, but how you say it" neatly sums up prosody - the changes to one's tone of voice that transmit meaning. Changes to speech rate, rhythm, volume, and pitch to convey emotion fall into the category of affective, or emotional, prosody. That is, the changes made to the voice to express feelings, such as happy or sad.

Following damage to the right side of the brain, such as in stroke, difficulties in affective prosody understanding and use have been observed. These findings have led researchers to view the right hemisphere as playing a critical role for emotional prosody. Affective prosody difficulties do not always spontaneously improve after acute right hemisphere stroke, and only a few evidenced-based treatments are available for these individuals. It is also understood that affective prosody difficulties can negatively impact social interactions and relationships, including those who care for individuals with emotional prosody difficulties. With miscommunication frequently occurring between those living with affective prosody disorders and those with whom these people interact, the risk of reduced quality of life and social isolation is possible and could be related to poorer health outcomes. Not only might there be personal burdens associated with poor management of communication difficulties in right hemisphere stroke and dementia, but there might also be economic burdens as well. In addition to counseling caregivers, family, and friends about the communication changes of loved ones, more evidenced-based speech and language treatment options are needed for those living with affective prosody disorders.

Cognitive-Linguistic and Speech-Language Assessment: During baseline testing, detailed speech-language and cognitive-communication behavioral testing will occur, focusing on aprosodia, awareness, motor speech, attention, verbal working memory, executive function, discourse, social participation, and emotion. Detailed testing focusing on aprosodia will occur after each Intervention Phase.

Functional near-infrared spectroscopy: Resting state functional connectivity as measured via functional near-infrared spectroscopy (fNIRS) will be assessed at Baseline, Post Phase I, and Post Phase II testing time points to track longitudinal change in functional connectivity patterns associated with targeted aprosodia intervention.

Aprosodia Intervention Phase: The aprosodia intervention will target receptive and expressive prosody over the course of four (4) weeks (12 sessions total). The receptive prosody intervention phase will occur for two weeks (6 sessions total, 3 sessions/week), and the expressive prosody intervention phase will occur for two weeks (6 sessions total, 3 sessions/week). Within each phase, the types of cues participants receive will also vary. Half of the expressive prosody intervention phase will use explicit cues (3 sessions total, 1 week), and the other half of the expressive prosody intervention phase will use implicit cues (3 sessions total, 1 week). This same setup for expressive prosody intervention phase will be used in the receptive prosody intervention phase. In addition to these implicit and explicit cues, expressive prosody intervention will also include feedback to increase awareness.

No-Intervention Phase: Participants will meet study personnel with the same frequency and duration (3 sessions/week, ~1 hour/session) during the No-Intervention Phase as during REACT. Sessions will comprise conversation about current events, recovery progress (including speech therapy goals targeted in outside intervention [if relevant]), hobbies, and other similar topics.

Inclusion Criteria:

• Ischemic stroke to the right cerebral hemisphere
• No history of other significant neurological disease or injury affecting the brain (excluding prior lacunar stroke, asymptomatic stroke, or TIA)
• Proficient speaker of English prior to stroke per self-report
• Capable of providing informed consent or indicating another to provide informed consent
• Ages 18-89
• Demonstration of receptive and/or expressive aprosodia on standardized measures of aprosodia
• Does not have severe cognitive impairment (MoCA > 9)
• Is not severely depressed (PHQ-9 < 20)
• Does not have more than mild motor speech impairment (ASRS < 16 and Dysarthria severity < 3)
• Normal or corrected-to-normal hearing and vision via screening tasks and self-report
• Medically stable
• Not taking any medications that may interfere with prosody processing
• Participation in speech therapy not targeting aprosodia

Exclusion Criteria:

• Ischemic stroke outside the right hemisphere or primary hemorrhagic stroke in the right hemisphere
• History of symptomatic stroke or significant neurological disease or injury affecting the brain
• No proficiency in English based on self-report
• Unable to provide informed consent or to indicate another to provide informed consent
• Children < 18 and adults 90+ years
• No demonstration of expressive or receptive aprosodia
• Severe cognitive-linguistic impairment (MoCA < 16)
• Severe depression (PHQ-9 > 19)
• More than mild motor speech impairment (ASRS > 15 + Dysarthria severity < 2)
• Uncorrected hearing/vision loss via screening tasks and self-report
• Not medically stable
• Reported medication use that may interfere with prosody processing
• Participating in outside speech therapy targeting aprosodia