Memory DeclineCoProMNCT07165977
Anti-inflammatory Probiotics in Cognitive Functioning
A study of Memory Decline and Cognitive Decline, run by University of Social Sciences and Humanities, Warsaw at 1 site in Poland.
Trial summary
The goal of this study is to explore the potential impact of an anti-inflammatory probiotic mixture of psychobiotics including Bifidobacterium longum Rosell®-175 and Lactobacillus helveticus Rosell®-52 on cognitive functions in older adults following either pro-inflammatory or anti-inflammatory diets. Read more about this study
- Who is it for?
- Ages 50 years and olderHealthy volunteers can take part
- Conditions the study is for
- Memory Decline, Cognitive Decline, Cognitive Aging
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 110 participants
- Where
- 1 sitePoland
- Study dates
- 25 Jan 2024to 31 Dec 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 50 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Aged 50 or older
- Signed written Informed Consent Form
- Score ≥28 on the Mini-Mental State Examination (MMSE)
- A willingness and motivation to follow the study protocol
Who cannot join
- Regular use of prebiotics, antibiotics, or antifungal medications
- Use of prebiotics, antibiotics, or antifungal medications within the past 3 months
- Diagnosed neurological disorder
- History of head injury with neurological consequences
- Left-handedness
Trial locations and contacts
1 site in 1 country.
About this study
Official title: The Impact of an Anti-inflammatory Probiotic Supplementation on Cognitive Functioning in the Elderly Population - the Moderating Role of the Dietary Patterns and Gut Microbiota
The goal of this study is to explore the potential impact of an anti-inflammatory probiotic mixture of psychobiotics including Bifidobacterium longum Rosell®-175 and Lactobacillus helveticus Rosell®-52 on cognitive functions in older adults following either pro-inflammatory or anti-inflammatory diets. According to recent findings, even short-term exposure to foods with pro- or anti-inflammatory properties may lead to corresponding negative or beneficial effects on cognitive functioning .
The main questions this study aims to answer are:
Read more
- How important is the initial dietary pattern for observing possible beneficial effects of probiotic supplementation? (Diet as a potential moderator)
- How important is the initial state of the gut microbiota for observing possible beneficial effects of probiotic supplementation? (Microbiota as a potential moderator)
- Is it possible to improve or slow down the decline in cognitive functions associated with aging with probiotic supplementation?
- Can probiotic supplementation counteract the negative effects of pro-inflammatory dietary patterns?
The investigators will compare probiotic to a placebo (a look-alike substance that contains no active ingredients) to determine whether probiotic is effective in enhancing cognitive function.
Participants:
- Take a probiotic or placebo capsule daily for 3 months
- Undergo a crossover after 3 months - those who initially took probiotics will switch to the placebo, and vice versa
- Visit SWPS University for screening (T0), baseline assessments before beginning supplementation (T1), and follow-up assessments at 3 months (T2) and 6 months (T3). The T2 visit occurs just before the crossover.
- Complete neuropsychological testing, questionnaires, and EEG recordings during the T1, T2, and T3 visits.
- Provide stool samples for gut microbiota analysis at the T1, T2, and T3 visits.
- Maintain their usual dietary habits throughout the study.
- Conditions
- Memory Decline, Cognitive Decline, Cognitive Aging
- Being tested
- Probiotic Supplementation (Bifidobacterium longum Rosell®-175 & Lactobacillus helveticus Rosell®-52) then placebo, Placebo Supplementation then Probiotic Supplementation (Bifidobacterium longum Rosell®-175 & Lactobacillus helveticus Rosell®-52)
- Keywords
- dietary patterns, probiotic intervention, cognitive functioning, EEG, ERP, gut microbiota, gut brain axis
- Medical subject headings
- Cognitive Dysfunction
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Probiotic Supplementation (Bifidobacterium longum Rosell®-175 & Lactobacillus helveticus Rosell®-52) then placeboDietary supplement
Each participant will take a probiotic mixture containing Bifidobacterium longum Rosell®-175 \& Lactobacillus helveticus Rosell®-52 and excipients: potato starch, magnesium stearate, and the capsule shell of hydroxypropyl methylcellulose. (Sanprobi Stress; Sanprobi sp. z o.o., sp.k., Szczecin, Poland) for 3 months.
- Dosage: One capsule per day, containing 3 × 10⁹ (3 billion) CFU*.
- Instructions: Take before 1:00 PM. Do not consume hot drinks immediately after taking the capsule.
After completion of the first phase, each participant will take a probiotic containing only the excipients, i.e. maize starch, maltodextrins, and the capsule shell for another 3 months.
- Dosage: One capsule per day.
- Instructions: Take before 1:00 PM. Do not consume hot drinks immediately after taking the capsule.
- CFU = Colony Forming Units
Placebo Supplementation then Probiotic Supplementation (Bifidobacterium longum Rosell®-175 & Lactobacillus helveticus Rosell®-52)Dietary supplement
Each participant will take a probiotic containing only the excipients, i.e. maize starch, maltodextrins, and the capsule shell for 3 months.
- Dosage: One capsule per day.
- Instructions: Take before 1:00 PM. Do not consume hot drinks immediately after taking the capsule.
After completion of the first phase, each participant will take a probiotic mixture containing Bifidobacterium longum Rosell®-175 \& Lactobacillus helveticus Rosell®-52 and excipients: potato starch, magnesium stearate, and the capsule shell of hydroxypropyl methylcellulose. (Sanprobi Stress; Sanprobi sp. z o.o., sp.k., Szczecin, Poland) for another 3 months.
- Dosage: One capsule per day, containing 3 × 10⁹ (3 billion) CFU*.
- Instructions: Take before 1:00 PM. Do not consume hot drinks immediately after taking the capsule.
- CFU = Colony Forming Units
| Study group | Role | What they receive |
|---|---|---|
| Anti-inflammatory diet + probiotic first | Experimental | This is a group of participants whose everyday dietary pattern was assessed as anti-inflammatory based on the Shivappa et al. (2014) equation, and who will receive probiotics during the first 3 months of the study. Receives: Dietary Supplement: Probiotic Supplementation (Bifidobacterium longum Rosell®-175 & Lactobacillus helveticus Rosell®-52) then placebo |
| Anti-inflammatory diet + placebo first | Experimental | This is a group of participants whose everyday dietary pattern was assessed as anti-inflammatory based on the Shivappa et al. (2014) equation, and who will receive placebo during the first 3 months of the study. Receives: Dietary Supplement: Placebo Supplementation then Probiotic Supplementation (Bifidobacterium longum Rosell®-175 & Lactobacillus helveticus Rosell®-52) |
| Pro-inflammatory diet + probiotic first | Experimental | This is a group of participants whose everyday dietary pattern was assessed as pro-inflammatory based on the Shivappa et al. (2014) equation, and who will receive probiotics during the first 3 months of the study. Receives: Dietary Supplement: Probiotic Supplementation (Bifidobacterium longum Rosell®-175 & Lactobacillus helveticus Rosell®-52) then placebo |
| Pro-inflammatory diet + placebo first | Experimental | This is a group of participants whose everyday dietary pattern was assessed as pro-inflammatory based on the Shivappa et al. (2014) equation, and who will receive placebo during the first 3 months of the study. Receives: Dietary Supplement: Placebo Supplementation then Probiotic Supplementation (Bifidobacterium longum Rosell®-175 & Lactobacillus helveticus Rosell®-52) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Differentiation score in California Verbal Learning Test (CVLT) to assess long-term memory
California Verbal Learning Test (CVLT) measure the verbal learning and memory. It measures how well individuals learn and recall verbal material, assessing both short-term and long-term memory. The Differentiation score measures the ability to distinguish between correct and incorrect responses. Scores range from 0 to 16, with higher scores indicating better outcome.
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in d' score in old/new recognition test (ONR) to assess long-term memory
The old/new word recognition task is designed to assess episodic memory. It is consisted of two phases: a learning phase and a recognition phase. During the learning phase, participants viewed 30 pictures on the computer. In the recognition phase, participants were presented with 30 "old" and 30 "new" pictures in random order and were asked to determine whether each picture had been shown during the learning phase.
To analyze episodic memory task we followed Macmillan and Creelman (2005) signal detection theory, where d' is the ability to discriminate between signal and noise (between old and new stimuli), H stands for the proportion of correct changes detected (hit rate), and F stands for the proportion of changes incorrectly reported (false alarm rate).
d' = zH - zF
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in N400 event-related potential (ERP) component amplitude to assess long-term memory
The N400 ERP component will be measured during an old/new word recognition task designed to assess episodic memory. The task involves presenting participants with previously studied ("old") and novel ("new") words while EEG is recorded. The N400 component-typically observed as a negative deflection peaking around 400 ms post-stimulus-is sensitive to familiarity and memory retrieval. A reduced N400 amplitude for old versus new words is interpreted as successful recognition. Changes in N400 amplitude over time will indicate modulation of episodic memory performance across the intervention.
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Secondary outcomes (17)
Changes in Beck Depression Inventory (BDI) total score to assess symptoms of depression
Scores range from 0 to 63, with higher scores indicating more severe depressive symptoms.
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Changes in the Fatigue Assessment Scale (FAS) total score to assess symptoms of chronic fatigue
Scores range from 10 to 50, with higher scores indicating greater fatigue.
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in the number of correctly marked target characters in the d2 Test of Attention (d2-R) - to assess attention.
Scores range from 0 to 308, with higher scores indicating better outcome.
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Concentration score in d2 Test of Attention (d2-R) - to assess attention
Scores range from 0 to 308, with higher scores indicating better outcome.
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Wechsler Adult Intelligence Scale (WAIS) Digit Symbol Substitution subtest total score to assess cognitive processing speed, visual-motor coordination, and sustained attention
Scores range from 0 to 39, with higher scores indicating better outcome.
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Wechsler Adult Intelligence Scale (WAIS) Digit Span Forward subset total score to assess short-term auditory memory
Scores range from 0 to 14, with higher scores indicating better outcome.
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Wechsler Adult Intelligence Scale (WAIS) Digit Span Backward subset total score to assess short-term auditory memory
Scores range from 0 to 14, with higher scores indicating better outcome.
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Wechsler Adult Intelligence Scale (WAIS) Block Design subtest total score to assess visual domains such as visuoperceptive, visuospatial and visuoconstructive functions
Scores range from 0 to 54, with higher scores indicating better outcome.
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Color Trails Test (CTT) total mistakes - CTT1 to assess several attention and executive functions especially perceptual tracking, sustained and divided attention
There is no predefined maximum number of errors in the test.
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Color Trails Test (CTT) total mistakes - CTT2 to assess several attention and executive functions especially perceptual tracking, sustained and divided attention
There is no predefined maximum number of errors in the test.
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Color Trails Test (CTT) completion time - CTT1 to assess several attention and executive functions especially perceptual tracking, sustained and divided attention
A maximum time limit of 240 seconds (4 minutes) is applied.
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Color Trails Test (CTT) completion time - CTT2 to assess several attention and executive functions especially perceptual tracking, sustained and divided attention
A maximum time limit of 240 seconds (4 minutes) is applied.
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Color Trails Test (CTT) Interference score - to assess several attention and executive functions especially perceptual tracking, sustained and divided attention
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in P300 event-related potential (ERP) component amplitude to assess attention
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Changes in diversity in microbial community in a single sample (alpha-diversity)
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Changes in diversity in microbial community between samples (beta-diversity)
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Changes in differential abundance of microbial community
Measured: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 Sep 2025
- Study start25 Jan 2024
- Primary completion30 Sep 2025 (estimated)
- Study completion31 Dec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Memory DeclineStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- Randomized, double-blind, and placebo-controlled study
- Masking
- Triple blind
- Who is masked
- Participant, Investigator, Outcomes assessor
- Enrolment
- 110 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Social Sciences and Humanities, Warsaw
- Sponsor type
- University, hospital or other
- Collaborators
- Sanprobi Sp. z o. o., National Science Centre, Poland
- Responsible party
- Principal investigator, Aneta Brzezicka, University of Social Sciences and Humanities, Warsaw
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07165977
- Sponsor's protocol ID
- Cognition-Probiotic-Microbiota
- Other IDs
- 2021/43/O/HS6/02074
- Acronym
- CoProM
- Status last verified
- Sep 2025
- First submitted
- 2 Sep 2025
- Last updated
- 17 Sep 2025
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes
Study at a glance
From the registry record, last updated by the sponsor on 17 Sep 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Impact of an Anti-inflammatory Probiotic Supplementation on Cognitive Functioning in the Elderly Population - the Moderating Role of the Dietary Patterns and Gut Microbiota
- ClinicalTrials.gov ID
- NCT07165977
- Acronym / sponsor ID
- CoProM / Cognition-Probiotic-Microbiota
- Conditions
- Memory Decline, Cognitive Decline, Cognitive Aging
- Keywords
- dietary patterns, probiotic intervention, cognitive functioning, EEG, ERP, gut microbiota, gut brain axis
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 110 participants (estimated)
- Lead sponsor
- University of Social Sciences and Humanities, WarsawUniversity, hospital or other
- Collaborators
- Sanprobi Sp. z o. o., National Science Centre, Poland
- Study start
- 25 Jan 2024 (actual)
- Primary completion
- 30 Sep 2025 (estimated)
- Study completion
- 31 Dec 2026 (estimated)
- First posted
- 10 Sep 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this study is to explore the potential impact of an anti-inflammatory probiotic mixture of psychobiotics including Bifidobacterium longum Rosell®-175 and Lactobacillus helveticus Rosell®-52 on cognitive functions in older adults following either pro-inflammatory or anti-inflammatory diets. According to recent findings, even short-term exposure to foods with pro- or anti-inflammatory properties may lead to corresponding negative or beneficial effects on cognitive functioning .
The main questions this study aims to answer are:
- How important is the initial dietary pattern for observing possible beneficial effects of probiotic supplementation? (Diet as a potential moderator)
- How important is the initial state of the gut microbiota for observing possible beneficial effects of probiotic supplementation? (Microbiota as a potential moderator)
- Is it possible to improve or slow down the decline in cognitive functions associated with aging with probiotic supplementation?
- Can probiotic supplementation counteract the negative effects of pro-inflammatory dietary patterns?
The investigators will compare probiotic to a placebo (a look-alike substance that contains no active ingredients) to determine whether probiotic is effective in enhancing cognitive function.
Participants:
- Take a probiotic or placebo capsule daily for 3 months
- Undergo a crossover after 3 months - those who initially took probiotics will switch to the placebo, and vice versa
- Visit SWPS University for screening (T0), baseline assessments before beginning supplementation (T1), and follow-up assessments at 3 months (T2) and 6 months (T3). The T2 visit occurs just before the crossover.
- Complete neuropsychological testing, questionnaires, and EEG recordings during the T1, T2, and T3 visits.
- Provide stool samples for gut microbiota analysis at the T1, T2, and T3 visits.
- Maintain their usual dietary habits throughout the study.
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Triple blind (participant, investigator, outcomes assessor)
- Number of arms
- 4
- Model description
- Randomized, double-blind, and placebo-controlled study
| Arm | Type | Receives |
|---|---|---|
| Anti-inflammatory diet + probiotic first | Experimental | Dietary Supplement: Probiotic Supplementation (Bifidobacterium longum Rosell®-175 & Lactobacillus helveticus Rosell®-52) then placeboThis is a group of participants whose everyday dietary pattern was assessed as anti-inflammatory based on the Shivappa et al. (2014) equation, and who will receive probiotics during the first 3 months of the study. |
| Anti-inflammatory diet + placebo first | Experimental | Dietary Supplement: Placebo Supplementation then Probiotic Supplementation (Bifidobacterium longum Rosell®-175 & Lactobacillus helveticus Rosell®-52)This is a group of participants whose everyday dietary pattern was assessed as anti-inflammatory based on the Shivappa et al. (2014) equation, and who will receive placebo during the first 3 months of the study. |
| Pro-inflammatory diet + probiotic first | Experimental | Dietary Supplement: Probiotic Supplementation (Bifidobacterium longum Rosell®-175 & Lactobacillus helveticus Rosell®-52) then placeboThis is a group of participants whose everyday dietary pattern was assessed as pro-inflammatory based on the Shivappa et al. (2014) equation, and who will receive probiotics during the first 3 months of the study. |
| Pro-inflammatory diet + placebo first | Experimental | Dietary Supplement: Placebo Supplementation then Probiotic Supplementation (Bifidobacterium longum Rosell®-175 & Lactobacillus helveticus Rosell®-52)This is a group of participants whose everyday dietary pattern was assessed as pro-inflammatory based on the Shivappa et al. (2014) equation, and who will receive placebo during the first 3 months of the study. |
Who may qualify
- Ages
- 50 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Aged 50 or older
- Signed written Informed Consent Form
- Score ≥28 on the Mini-Mental State Examination (MMSE)
- A willingness and motivation to follow the study protocol
Key exclusion criteria (5 listed)
- Regular use of prebiotics, antibiotics, or antifungal medications
- Use of prebiotics, antibiotics, or antifungal medications within the past 3 months
- Diagnosed neurological disorder
- History of head injury with neurological consequences
- Left-handedness
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Probiotic Supplementation (Bifidobacterium longum Rosell®-175 & Lactobacillus helveticus Rosell®-52) then placeboEach participant will take a probiotic mixture containing Bifidobacterium longum Rosell®-175 \& Lactobacillus helveticus Rosell®-52 and excipients: potato starch, magnesium stearate, and the capsule shell of hydroxypropyl methylcellulose. (Sanprobi Stress; Sanprobi sp. z o.o., sp.k., Szczecin, Poland) for 3 months. * Dosage: One capsule per day, containing 3 × 10⁹ (3 billion) CFU*. * Instructions: Take before 1:00 PM. Do not consume hot drinks immediately after taking the capsule. After completion of the first phase, each participant will take a probiotic containing only the excipients, i.e. maize starch, maltodextrins, and the capsule shell for another 3 months. * Dosage: One capsule per day. * Instructions: Take before 1:00 PM. Do not consume hot drinks immediately after taking the capsule. * CFU = Colony Forming Units | Dietary supplement | Anti-inflammatory diet + probiotic first, Pro-inflammatory diet + probiotic first |
| Placebo Supplementation then Probiotic Supplementation (Bifidobacterium longum Rosell®-175 & Lactobacillus helveticus Rosell®-52)Each participant will take a probiotic containing only the excipients, i.e. maize starch, maltodextrins, and the capsule shell for 3 months. * Dosage: One capsule per day. * Instructions: Take before 1:00 PM. Do not consume hot drinks immediately after taking the capsule. After completion of the first phase, each participant will take a probiotic mixture containing Bifidobacterium longum Rosell®-175 \& Lactobacillus helveticus Rosell®-52 and excipients: potato starch, magnesium stearate, and the capsule shell of hydroxypropyl methylcellulose. (Sanprobi Stress; Sanprobi sp. z o.o., sp.k., Szczecin, Poland) for another 3 months. * Dosage: One capsule per day, containing 3 × 10⁹ (3 billion) CFU*. * Instructions: Take before 1:00 PM. Do not consume hot drinks immediately after taking the capsule. * CFU = Colony Forming Units | Dietary supplement | Anti-inflammatory diet + placebo first, Pro-inflammatory diet + placebo first |
Primary outcome
Change in Differentiation score in California Verbal Learning Test (CVLT) to assess long-term memory
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
California Verbal Learning Test (CVLT) measure the verbal learning and memory. It measures how well individuals learn and recall verbal material, assessing both short-term and long-term memory. The Differentiation score measures the ability to distinguish between correct and incorrect responses. Scores range from 0 to 16, with higher scores indicating better outcome.
Change in d' score in old/new recognition test (ONR) to assess long-term memory
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
The old/new word recognition task is designed to assess episodic memory. It is consisted of two phases: a learning phase and a recognition phase. During the learning phase, participants viewed 30 pictures on the computer. In the recognition phase, participants were presented with 30 "old" and 30 "new" pictures in random order and were asked to determine whether each picture had been shown during the learning phase. To analyze episodic memory task we followed Macmillan and Creelman (2005) signal detection theory, where d' is the ability to discriminate between signal and noise (between old and new stimuli), H stands for the proportion of correct changes detected (hit rate), and F stands for the proportion of changes incorrectly reported (false alarm rate). d' = zH - zF
Change in N400 event-related potential (ERP) component amplitude to assess long-term memory
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
The N400 ERP component will be measured during an old/new word recognition task designed to assess episodic memory. The task involves presenting participants with previously studied ("old") and novel ("new") words while EEG is recorded. The N400 component-typically observed as a negative deflection peaking around 400 ms post-stimulus-is sensitive to familiarity and memory retrieval. A reduced N400 amplitude for old versus new words is interpreted as successful recognition. Changes in N400 amplitude over time will indicate modulation of episodic memory performance across the intervention.
17 secondary outcomes
Changes in Beck Depression Inventory (BDI) total score to assess symptoms of depression
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Changes in the Fatigue Assessment Scale (FAS) total score to assess symptoms of chronic fatigue
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in the number of correctly marked target characters in the d2 Test of Attention (d2-R) - to assess attention.
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Concentration score in d2 Test of Attention (d2-R) - to assess attention
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Wechsler Adult Intelligence Scale (WAIS) Digit Symbol Substitution subtest total score to assess cognitive processing speed, visual-motor coordination, and sustained attention
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Wechsler Adult Intelligence Scale (WAIS) Digit Span Forward subset total score to assess short-term auditory memory
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Wechsler Adult Intelligence Scale (WAIS) Digit Span Backward subset total score to assess short-term auditory memory
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Wechsler Adult Intelligence Scale (WAIS) Block Design subtest total score to assess visual domains such as visuoperceptive, visuospatial and visuoconstructive functions
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Color Trails Test (CTT) total mistakes - CTT1 to assess several attention and executive functions especially perceptual tracking, sustained and divided attention
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Color Trails Test (CTT) total mistakes - CTT2 to assess several attention and executive functions especially perceptual tracking, sustained and divided attention
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Color Trails Test (CTT) completion time - CTT1 to assess several attention and executive functions especially perceptual tracking, sustained and divided attention
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Color Trails Test (CTT) completion time - CTT2 to assess several attention and executive functions especially perceptual tracking, sustained and divided attention
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in Color Trails Test (CTT) Interference score - to assess several attention and executive functions especially perceptual tracking, sustained and divided attention
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Change in P300 event-related potential (ERP) component amplitude to assess attention
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Changes in diversity in microbial community in a single sample (alpha-diversity)
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Changes in diversity in microbial community between samples (beta-diversity)
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Changes in differential abundance of microbial community
Time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 17 Sep 2025.
- Individual participant dataSharing planned: Yes
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Predicting Declines in Attention and Memory During a Prolonged Mental Task
Mental Fatigue, Cognitive Performance
Recruiting
Lifestyle Intervention in the Memory Clinics of General and Academic Hospitals Trial
Lifestyle Intervention, Lifestyle Risk Reduction
Not yet recruiting
Study of Bedroom Environment Sleep Intervention at Home for Older Adults Living Alone With Memory Concerns
Subjective Cognitive Decline (SCD), Mild Cognitive Impairment (MCI)
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study of Memory Decline and Cognitive Decline, run by University of Social Sciences and Humanities, Warsaw at 1 site in Poland.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 17 Sep 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Poland. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in Differentiation score in California Verbal Learning Test (CVLT) to assess long-term memory (time frame: Baseline (prior to intervention), at the end of the 3-month probiotic/placebo supplementation period, and again 3 months after the crossover.). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 17 Sep 2025.