LLM-Driven Daily Conversation for Cognitive Health in Older Adults

Official title

A Large Language Model-Driven Daily Conversation Cognitive Interaction Platform: Feasibility and Preliminary Efficacy in Older Adults at High Risk of Dementia

Overview

This study will develop and test a daily conversation platform that uses a large language model, a type of artificial intelligence, to support cognitive health in older adults at high risk of dementia. The platform will guide participants through voice-based conversations about topics that interest them. The conversations are designed to engage memory, attention, language, planning and problem-solving, and the ability to understand social situations. The platform will also analyze conversation data and create a report describing the participant's cognitive performance. The study has two stages. In the first stage, 15 participants will test the platform through two 20-minute conversation sessions. This group will include healthy younger adults, older adults with normal cognitive function, and older adults with cognitive difficulties. Participants will provide feedback on how easy and acceptable the platform is to use. In the second stage, 60 older adults at high risk of dementia will be randomly assigned to one of three groups. The groups will receive either conversation-based cognitive activities using the platform, interest-based news reading activities, or weekly health education while waiting to receive the intervention. The study activities will continue for 12 weeks. Researchers will compare changes in cognitive function, emotional well-being, loneliness, social connection, and user experience before and after the study. The main goals are to learn whether the platform is practical and acceptable for home use and whether it may help support cognitive and psychosocial health.

Detailed description

Cognitive decline is an important health concern in aging populations. Early cognitive stimulation that is meaningful and related to daily life may help older adults maintain cognitive and psychosocial function. However, many digital cognitive programs use repetitive exercises and provide limited opportunities for natural social interaction.

This study aims to develop and evaluate a large language model-driven daily conversation cognitive interaction platform for older adults at high risk of dementia. The platform uses voice-based, semi-structured conversations based on topics that interest each participant. The conversations are designed to stimulate five cognitive areas: memory, attention, language, executive function, and social cognition.

During each session, participants speak with the platform using natural conversation. The system converts speech into text and analyzes selected features of the participant's responses, such as response accuracy, language fluency, organization of ideas, attention to the conversation, and understanding of social situations. The system then generates a cognitive profile report. This report is intended to provide understandable information about performance across the five cognitive areas and is not intended to diagnose dementia.

The study will be conducted in two stages.

Stage 1 will evaluate the initial feasibility and usability of the platform. Fifteen participants will be enrolled, including five healthy younger adults, five older adults with normal cognitive function, and five older adults with cognitive difficulties. Each participant will complete two 20-minute conversation sessions. Participants will then complete questionnaires about system usability and intervention acceptability. Their comments and experiences will be used to improve the platform before the randomized trial.

Stage 2 will use a single-blind, randomized controlled design. A total of 60 older adults at high risk of dementia will be randomly assigned in equal numbers to one of three groups:

Large language model conversation group: Participants will complete voice-based cognitive conversations with the platform. The activities will include exercises targeting memory, attention, language, executive function, and social cognition.

Interest-based news reading group: Participants will read news content selected according to their interests and complete questions related to the content.

Waitlist control group: Participants will receive weekly health education materials during the initial study period.

The interventions will continue for 12 weeks. Cognitive and psychosocial outcomes will be assessed before and after the intervention. The cognitive assessments will examine overall cognitive function and specific abilities such as memory, attention, language, processing speed, executive function, and social cognition. Psychosocial assessments will examine depressive symptoms, loneliness, and social connection.

The study will also evaluate intervention completion, system usability, and intervention acceptability. The findings will be used to determine whether the platform is feasible for home-based use and whether it shows preliminary benefits for cognitive and psychosocial health in older adults at high risk of dementia.

Interventions

• Behavioral LLM Conversation Cognitive Interaction
  A voice-based cognitive stimulation program delivered through a large language model-driven conversational platform. The platform uses topics selected according to each participant's interests and guides natural conversations designed to engage memory, attention, language, executive function, and social cognition. The platform provides topic summaries, asks questions, responds to participants' answers, and adjusts the depth of follow-up questions based on response quality. Conversation response
• Behavioral Interest-Based Knowledge Reading
  A digital cognitive activity that provides short news and knowledge summaries based on participants' interests. The content includes both familiar and unfamiliar topics, as well as preferred and non-preferred topics, to provide varied cognitive challenges. Participants answer multiple-choice questions about each summary. The questions are designed to engage reading comprehension, attention, and memory for the presented information.
• Behavioral Waitlist Health Education
  General health education materials for older adults delivered through the LINE platform. The materials provide information related to healthy aging and general health management but do not include structured conversational cognitive stimulation or interest-based reading exercises.

Primary outcome measures

• Verbal fluency test [Time frame: Change from Baseline at 13 weeks]
• Chinese Verbal Learning Test [Time frame: Change from Baseline at 13 weeks]

Secondary outcome measures (12)

• Digit Span subtest [Time frame: Change from Baseline at 13 weeks]
• Cookie Theft Picture [Time frame: Change from Baseline at 13 weeks]
• Digit Symbol Substitution Test [Time frame: Change from Baseline at 13 weeks]
• Stroop Color and Word Test [Time frame: Change from Baseline at 13 weeks]
• Color Trails Test [Time frame: Change from Baseline at 13 weeks]
• Theory of Mind Scale [Time frame: Change from Baseline at 13 weeks]
• Geriatric Depression Scale- 15 [Time frame: Change from Baseline at 13 weeks]
• University of California, Los Angeles, Loneliness Scale [Time frame: Change from Baseline at 13 weeks]
• Chinese Happiness Inventory [Time frame: Change from Baseline at 13 weeks]
• Visual Analogue Scale of Subjective Cognitive Function [Time frame: Change from Baseline at 13 weeks]
• System Usability Scale [Time frame: Within 1 week after completion of the 12-week intervention (Week 13)]
• Acceptability of Intervention Measure [Time frame: Within 1 week after completion of the 12-week intervention (Week 13)]

Eligibility criteria

Inclusion criteria

Stage 1: Feasibility Study

Participants must belong to one of the following groups:

Healthy younger adults aged 18 to 40 years. Older adults with normal cognitive function aged 65 years or older and a Montreal Cognitive Assessment score of 24 or higher.

Older adults with cognitive impairment aged 65 years or older and a Montreal Cognitive Assessment score of 18 to 23.

Participants must have completed at least elementary school, corresponding to 6 or more years of education.

Participants must be able to read and write Chinese, communicate in Chinese, and understand the study content.

Participants must be able to use a tablet or smartphone independently or with assistance from a family member.

Participants must have sufficient hearing and vision, with usual corrective devices if needed, to complete the study tasks.

Stage 2: Preliminary Efficacy Study

Participants must be aged 65 years or older.

Participants must be considered at high risk of dementia by meeting at least one of the following conditions:

• Subjective cognitive decline:

A Subjective Cognitive Decline Questionnaire score greater than 7 out of 24.

A response of yes to both of the following questions:

Compared with your previous usual condition, do you have memory problems? Have your family members or close contacts noticed memory problems compared with your previous condition? Performance within the normal range on standardized cognitive tests, defined as scores no more than 1.5 standard deviations below age- and education-adjusted norms on the Color Trails Test and memory-related assessments.

• Mild cognitive impairment:

A diagnosis of mild cognitive impairment made by a neurologist or psychiatrist according to accepted diagnostic criteria.

Evidence of memory performance at least 1.5 standard deviations below age- and education-adjusted normative values on at least one subtest of the Wechsler Memory Scale, Third Edition.

• Limited social interaction:

Living alone, living with a person who cannot provide care, or living with a person who is absent for at least 3 days per week; or A score below 12 on the 6-item Lubben Social Network Scale.

• Chronic disease:

A physician diagnosis of hypertension or diabetes for at least 1 year; and A need for ongoing medication or lifestyle management. Participants must have completed at least elementary school, corresponding to 6 or more years of education.

Participants must be able to read and write Chinese, communicate in Chinese, and understand news and study-related content.

Participants must be able to use a tablet or smartphone independently or with assistance from a family member.

Participants must have sufficient hearing and vision, with usual corrective devices if needed, to complete the conversation and reading tasks.

Exclusion criteria

A diagnosis of dementia or a severe neurodegenerative disorder, such as moderate-to-advanced Parkinson disease or Huntington disease.

A history of a severe psychiatric disorder, such as schizophrenia or severe bipolar disorder, or current acute psychiatric symptoms that may interfere with understanding or responding during conversations.

A major neurological event within the previous 6 months, such as stroke or severe traumatic brain injury, that may substantially affect cognitive or language function.

Severe hearing, speech, or language impairment that prevents basic verbal communication, even when assistive devices are used.

An acute medical illness, active infection, or any condition considered by a physician to make study participation inappropriate.

Inability to complete a 20-minute conversation task or unwillingness to allow collection of interaction data.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Prevention

Study locations

Center list to be confirmed — check the primary protocol.

Identifiers

NCT: NCT07751510 · N202605135

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗