Speech Tasks for Understanding Brain Processing of Language

Recruiting in Palo Alto (17 mi)

Overseen byEdward F Chang, MD

Age: 18+

Sex: Any

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Academic

Waitlist Available

Sponsor: University of California, San Francisco

No Placebo Group

Trial Summary

What is the purpose of this trial?The overall goal of this study is to reveal the fundamental neural mechanisms that underlie comprehension across human spoken languages. An understanding of how speech is coded in the brain has significant implications for the development of new diagnostic and rehabilitative strategies for language disorders (e.g. aphasia, dyslexia, autism, et alia). The basic mechanisms underlying comprehension of spoken language are unknown. Researchers are only beginning to understand how the human brain extracts the most fundamental linguistic elements (consonants and vowels) from a complex and highly variable acoustic signal. Traditional theories have posited a 'universal' phonetic inventory shared by all humans, but this has been challenged by other newer theories that each language has its own unique and specialized code. An investigation of the cortical representation of speech sounds across languages can likely shed light on this fundamental question. Previous research has implicated the superior temporal cortex in the processing of speech sounds. Most of this work has been entirely carried out in English. The recording of neural activity directly from the cortical surface from individuals with different language experience is a promising approach since it can provide both high spatial and temporal resolution. This study will examine the mechanisms of phonetic encoding, by utilizing neurophysiological recordings obtained during neurosurgical procedures. High-density electrode arrays, advanced signal processing, and direct electrocortical stimulation will be utilized to unravel both local and population encoding of speech sounds in the lateral temporal cortex. This study will also examine the neural encoding of speech in patients who are monolingual and bilingual in Mandarin, Spanish, and English, the most common spoken languages worldwide, and feature important contrastive differences of pitch, formant, and temporal envelope. A cross-linguistic approach is critical for a true understanding of language, while also striving to achieve a broader approach of diversity and inclusion in neuroscience of language.

Eligibility Criteria

This trial is for individuals at UCSF with epilepsy or brain tumors who are undergoing surgery involving electrode implantation. They must be able to perform study tasks and have electrodes in at least two key brain areas. Those unable to consent, with significant cerebral lesions, or cognitive deficits that prevent task completion cannot participate.

Inclusion Criteria

I have electrodes implanted in key areas and can participate in study tasks.

I am having surgery at UCSF for epilepsy or a brain tumor, involving electrode implantation.

Exclusion Criteria

I am able to understand and complete study tasks without difficulty.

I am unable or unwilling to give consent for this trial.

I have significant brain lesions.

Participant Groups

The study aims to understand how the brain processes speech across different languages by recording neural activity during surgery. It uses high-density electrodes and signal processing on patients speaking Mandarin, Spanish, and English to explore phonetic encoding in the temporal cortex.

1Treatment groups

Experimental Treatment

Group I: Electrocorticography (ECoG) recording during Speech TasksExperimental Treatment1 Intervention

Participants listened to 20-minute Speech Tasks while ECoG signals for neural activity was recorded during their intraoperative procedure or inpatient hospitalization at the University of California, San Francisco (UCSF).