Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
The purpose of this study is to understand the relationship between psychotic symptoms and social functioning in individuals with schizophrenia spectrum disorders. Our goal is to determine whether stimulating the brain using transcranial Direct Current Stimulation (tDCS) can improve symptoms and daily functioning.
Paranoid ideation is a common delusion experienced by individuals with schizophrenia spectrum disorders (SSD) that negatively impacts social interactions and quality of life. Therefore, efforts to reduce paranoid thinking via neuromodulation techniques [e.g., transcranial direct current stimulation (tDCS)] are in development, with amygdala-prefrontal cortex (PFC) circuits targeted as critical components of the neural mechanisms underlying paranoia.
This project aims to alleviate paranoia and improve social functioning in individuals with SSD by implementing tDCS to ventrolateral PFC. A double-blind, within-subjects, crossover design will be used to compare the effects of active vs. sham tDCS. Ecological Momentary Assessments (EMA) will also be utilized to quantify any delayed stimulation effects in daily social interactions.
Not provided
Not provided
Not provided
Not provided
Not provided
| Label | Type | Description | Intervention Names |
|---|---|---|---|
| Active anodal tDCS first, then Sham tDCS | Experimental | Active anodal tDCS (40 minutes; divided into two 20-minutes sessions) followed by behavioral testing; Washout (about 1 week); sham stimulation (40 minutes; divided into two 20-minutes sessions) followed by behavioral testing. |
|
| Sham tDCS first, then Active anodal tDCS | Sham Comparator | Sham tDCS (40 minutes; divided into two 20-minutes sessions) followed by behavioral testing; Washout (about 1 week); Active anodal tDCS (40 minutes; divided into two 20-minutes sessions) followed by behavioral testing Intervention. |
|
| Name | Type | Description | Arm Group Labels | Other Names |
|---|---|---|---|---|
| tDCS | Device | active anodal tDCS and sham tDCS |
|
| Measure | Description | Time Frame |
|---|---|---|
| The State Social Paranoia Scale (SSPS) | Paranoid ideation was measured by the State Social Paranoia Scale (SSPS). Participants indicated how much they agree with each of 20 statements (e.g., "Someone was hostile towards me", "Someone was trying to isolate me") using a 5-point Likert scale (1 = do not agree, 5 = totally agree). Scores range from 20-100, and higher scores represent higher state paranoid ideation. | The assessment was completed before the stimulation and 30 minutes after completion of the active/sham stimulation |
| Ecological Momentary Assessment (EMA)-Based Paranoia | Paranoid ideation was measured by Ecological Momentary Assessment (EMA), which involved questions about feelings of paranoia in daily life. The paranoia-related question is as follows: "Since the past alarm, how much have you had thoughts that you really can't trust other people?" The score for this item ranges from 1 to 7, with a higher score indicating a higher level of paranoid thinking. | Change in daily paranoia feelings was assessed from the pre-stimulation EMA period (7 days before the stimulation visit) to the post-stimulation EMA period (7 days after the stimulation visit) |
| Birchwood Social Functioning Scale (SFS) | Social functioning was measured by the Birchwood Social Functioning Scale (SFS). This scale measures social adjustment based on self-reports (4- or 5-point scales), with higher total scores indicating better social functioning (range = 0-223). | The assessment was completed 30 minutes after completion of the active/sham stimulation |
| Ecological Momentary Assessment (EMA)-Based Social Functioning | Social functioning was measured by Ecological Momentary Assessment (EMA) (i.e., questions about daily interactions with others). Two subscores were generated: social interaction frequency (score ranges from 0-5, a higher score indicates more frequent social interactions), social interaction motivation and experience (scores range from 1-7, a higher score indicates higher motivations to interact with others and better experiences during these interactions). |
| Measure | Description | Time Frame |
|---|---|---|
| The Trustworthiness Task | Paranoid ideation was measured by the Trustworthiness Task. This task requires participants to indicate how much they trust each of 60 grayscale facial stimuli along a 7-point Likert scale (-3 = very untrustworthy, 3 = very trustworthy). Total scores were calculated by averaging across responses and hence varied from -3 to +3, with higher values indicating a greater tendency to trust others. |
Not provided
Inclusion Criteria:
Exclusion Criteria:
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| Facility | Status | City | State | ZIP | Country | Contacts |
|---|---|---|---|---|---|---|
| The Unversity of Texas at Dallas | Richardson | Texas | 75080 | United States |
| PubMed Identifier | Type | Citation | Retractions |
|---|---|---|---|
| 39855408 | Derived | Fan L, Carrico S, Zhu Y, Ackerman RA, Pinkham AE. Transcranial Direct Current Stimulation Improves Paranoia and Social Functioning in Schizophrenia: A Randomized Clinical Trial. Biol Psychiatry. 2025 Jul 15;98(2):135-143. doi: 10.1016/j.biopsych.2025.01.011. Epub 2025 Jan 22. |
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
A total of 50 participants were enrolled and eventually completing the whole procedure.
Not provided
| ID | Title | Description |
|---|---|---|
| FG000 | Active Anodal tDCS First, Then Sham tDCS | Active anodal tDCS (40 minutes; divided into two 20-minutes sessions) followed by behavioral testing; Washout (about 1 week); sham stimulation (40 minutes; divided into two 20-minutes sessions) followed by behavioral testing. tDCS: active anodal tDCS and sham tDCS |
| FG001 | Sham tDCS First, Then Active Anodal tDCS | Sham tDCS (40 minutes; divided into two 20-minutes sessions) followed by behavioral testing; Washout (about 1 week); Active anodal tDCS (40 minutes; divided into two 20-minutes sessions) followed by behavioral testing Intervention. tDCS: active anodal tDCS and sham tDCS |
| Title | Milestones | Reasons Not Completed | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Overall Study |
|
Not provided
Not provided
| ID | Title | Description |
|---|---|---|
| BG000 | Active Anodal tDCS First, Then Sham tDCS | Active anodal tDCS (40 minutes; divided into two 20-minutes sessions) followed by behavioral testing; Washout (about 1 week); sham stimulation (40 minutes; divided into two 20-minutes sessions) followed by behavioral testing. tDCS: active anodal tDCS and sham tDCS |
| BG001 |
| Units | Counts |
|---|---|
| Participants |
|
| Title | Description | Population Description | Parameter Type | Dispersion Type | Unit of Measure | Calculate Percentage | Denominator Units Selected | Denominators | Classes |
|---|---|---|---|---|---|---|---|---|---|
| Age, Continuous | Mean |
| Type | Title | Description | Population Description | Reporting Status | Anticipated Posting Date | Parameter Type | Dispersion Type | Unit of Measure | Calculate Percentage | Time Frame | Units Analyzed | Denominator Units Selected | Arm/Group Information | Denominators | Classes | Analyses | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Primary | The State Social Paranoia Scale (SSPS) | Paranoid ideation was measured by the State Social Paranoia Scale (SSPS). Participants indicated how much they agree with each of 20 statements (e.g., "Someone was hostile towards me", "Someone was trying to isolate me") using a 5-point Likert scale (1 = do not agree, 5 = totally agree). Scores range from 20-100, and higher scores represent higher state paranoid ideation. | Posted | Mean | Standard Deviation | The change score of SSPS (pre - post) | The assessment was completed before the stimulation and 30 minutes after completion of the active/sham stimulation |
|
Immediately after the stimulation visit, up to 24 hours
Not provided
Not provided
| ID | Title | Description | Deaths (Affected) | Deaths (At Risk) | Serious Events (Affected) | Serious Events (At Risk) | Other Events (Affected) | Other Events (At Risk) |
|---|---|---|---|---|---|---|---|---|
| EG000 | Active Visit | Active anodal tDCS (40 minutes; divided into two 20-minutes sessions) followed by behavioral testing |
Not provided
Not provided
The inherent limitations of the assessment tools for measuring social functioning in the lab may have impacted the findings.
| Title | Organization | Phone | Extension | |
|---|---|---|---|---|
| Dr. Linlin Fan | University of Texas at Dallas | +(853) 8822 4226 | linlin.fan@utdallas.edu; linlinfan@um.edu.mo |
Not provided
| Type | Includes Protocol | Includes SAP | Includes ICF | Document Label | Document Date | Document Uploaded Date | Document File Name |
|---|---|---|---|---|---|---|---|
| Prot_SAP | Yes | Yes | No | Study Protocol and Statistical Analysis Plan | Nov 19, 2024 | Nov 19, 2024 | Prot_SAP_000.pdf |
Not provided
Not provided
Not provided
| ID | Term |
|---|---|
| D012559 | Schizophrenia |
| D011618 | Psychotic Disorders |
| ID | Term |
|---|---|
| D019967 | Schizophrenia Spectrum and Other Psychotic Disorders |
| D001523 | Mental Disorders |
Not provided
Not provided
| ID | Term |
|---|---|
| D065908 | Transcranial Direct Current Stimulation |
| ID | Term |
|---|---|
| D004599 | Electric Stimulation Therapy |
| D013812 | Therapeutics |
| D003295 | Convulsive Therapy |
| D013000 | Psychiatric Somatic Therapies |
Not provided
Not provided
Participants will complete active and sham simulation sessions in a randomized, counterbalanced order about one week apart.
Not provided
Not provided
Not provided
| Change in daily interactions was assessed from the pre-stimulation EMA period (7 days before the stimulation visit) to the post-stimulation EMA period (7 days after the stimulation visit) |
| The assessment was completed 30 minutes after completion of the active/sham stimulation |
| The Scrambled-sentences Task (SST) | Paranoid ideation was measured by the Scrambled-sentences task (SST). This task measures the level of paranoia by asking participants to create sentences of either paranoid or nonparanoid meanings, with a greater percentage indicating a higher level of paranoid interpretation bias (range = 0-1). | The assessment was completed 30 minutes after completion of the active/sham stimulation |
| The Ambiguous Intentions Hostility Questionnaire (AIHQ) | Paranoid ideation was measured by the Ambiguous Intentions Hostility Questionnaire (AIHQ). Three subscores were generated: AIHQ (blame) (ranging from 3-16, with a higher score indicating a higher level of blaming tendency), AIHQ (hostility) (ranging from 1-5, with a higher score indicating a higher level of hostility), AIHQ (aggression) (ranging from 1-5, with a higher score indicating a higher level of aggression). | The assessment was completed 30 minutes after completion of the active/sham stimulation |
| The Hostility Scale of the Personality Inventory for DSM-5 (PID-5-HS) | Paranoid ideation was measured by the Hostility Scale of the Personality Inventory for DSM-5 (PID-5-HS). PID-5-HS contains 10 self-report items assessing pathological hostility. A total score (range from 0-30) was generated to reflect overall hostility level, with higher total scores indicating more hostility. | The assessment was completed 30 minutes after completion of the active/sham stimulation |
| Sham tDCS First, Then Active Anodal tDCS |
Sham tDCS (40 minutes; divided into two 20-minutes sessions) followed by behavioral testing; Washout (about 1 week); Active anodal tDCS (40 minutes; divided into two 20-minutes sessions) followed by behavioral testing Intervention. tDCS: active anodal tDCS and sham tDCS |
| BG002 | Total | Total of all reporting groups |
| years |
|
| Sex: Female, Male | Count of Participants | Participants |
|
| Ethnicity (NIH/OMB) | Count of Participants | Participants |
|
| Race (NIH/OMB) | Count of Participants | Participants |
|
| Region of Enrollment | Number | participants |
|
| Handedness | Number | participants |
|
| Years of education | Mean | Standard Deviation | years |
|
| The Wide Range Achievement Test-Reading recognition subtest 4 (WRAT-4) | This scale measures the Intelligence Quotient (IQ). A total final standardized score (adjusted by age) is computed. The range of this total score is from 55 to 145. A higher total score indicates a higher IQ and suggests that the participant is more intelligent. | Mean | Standard Deviation | units on a scale |
|
| Chlorpromazine (CPZ)-equivalent | This measures the dosage of antipsychotic medications that the participant is taking. A total final score is computed. The range of this total score is from 0 to unlimited. A higher score indicates a higher dosage of antipsychotic medications. | Mean | Standard Deviation | mg |
|
| Diagnoses | Two types of diagnoses were included in this study, including schizophrenia (SCZ) and schizoaffective disorder (SCZ-A). Diagnoses were determined via Mini International Neuropsychiatric Interview (MINI) and Structured Clinical Interview for DSM Disorders-Psychosis Module (SCID-P). | Number | participants |
|
| Current/recent paranoia | Number | participants |
|
|
|
|
| Primary | Ecological Momentary Assessment (EMA)-Based Paranoia | Paranoid ideation was measured by Ecological Momentary Assessment (EMA), which involved questions about feelings of paranoia in daily life. The paranoia-related question is as follows: "Since the past alarm, how much have you had thoughts that you really can't trust other people?" The score for this item ranges from 1 to 7, with a higher score indicating a higher level of paranoid thinking. | Only 47 (out of 50) participants completed this measure. | Posted | Mean | Standard Deviation | units on a scale | Change in daily paranoia feelings was assessed from the pre-stimulation EMA period (7 days before the stimulation visit) to the post-stimulation EMA period (7 days after the stimulation visit) |
|
|
|
|
| Primary | Birchwood Social Functioning Scale (SFS) | Social functioning was measured by the Birchwood Social Functioning Scale (SFS). This scale measures social adjustment based on self-reports (4- or 5-point scales), with higher total scores indicating better social functioning (range = 0-223). | Posted | Mean | Standard Deviation | units on a scale | The assessment was completed 30 minutes after completion of the active/sham stimulation |
|
|
|
|
| Primary | Ecological Momentary Assessment (EMA)-Based Social Functioning | Social functioning was measured by Ecological Momentary Assessment (EMA) (i.e., questions about daily interactions with others). Two subscores were generated: social interaction frequency (score ranges from 0-5, a higher score indicates more frequent social interactions), social interaction motivation and experience (scores range from 1-7, a higher score indicates higher motivations to interact with others and better experiences during these interactions). | Only 47 (out of 50) participants completed this measure. | Posted | Mean | Standard Deviation | score on a scale | Change in daily interactions was assessed from the pre-stimulation EMA period (7 days before the stimulation visit) to the post-stimulation EMA period (7 days after the stimulation visit) |
|
|
|
|
| Secondary | The Trustworthiness Task | Paranoid ideation was measured by the Trustworthiness Task. This task requires participants to indicate how much they trust each of 60 grayscale facial stimuli along a 7-point Likert scale (-3 = very untrustworthy, 3 = very trustworthy). Total scores were calculated by averaging across responses and hence varied from -3 to +3, with higher values indicating a greater tendency to trust others. | Posted | Mean | Standard Deviation | score on a scale | The assessment was completed 30 minutes after completion of the active/sham stimulation |
|
|
|
|
| Secondary | The Scrambled-sentences Task (SST) | Paranoid ideation was measured by the Scrambled-sentences task (SST). This task measures the level of paranoia by asking participants to create sentences of either paranoid or nonparanoid meanings, with a greater percentage indicating a higher level of paranoid interpretation bias (range = 0-1). | Only 49 (out of 50) participants completed this task. | Posted | Mean | Standard Deviation | score on a scale | The assessment was completed 30 minutes after completion of the active/sham stimulation |
|
|
|
|
| Secondary | The Ambiguous Intentions Hostility Questionnaire (AIHQ) | Paranoid ideation was measured by the Ambiguous Intentions Hostility Questionnaire (AIHQ). Three subscores were generated: AIHQ (blame) (ranging from 3-16, with a higher score indicating a higher level of blaming tendency), AIHQ (hostility) (ranging from 1-5, with a higher score indicating a higher level of hostility), AIHQ (aggression) (ranging from 1-5, with a higher score indicating a higher level of aggression). | Posted | Mean | Standard Deviation | score on a scale | The assessment was completed 30 minutes after completion of the active/sham stimulation |
|
|
|
|
| Secondary | The Hostility Scale of the Personality Inventory for DSM-5 (PID-5-HS) | Paranoid ideation was measured by the Hostility Scale of the Personality Inventory for DSM-5 (PID-5-HS). PID-5-HS contains 10 self-report items assessing pathological hostility. A total score (range from 0-30) was generated to reflect overall hostility level, with higher total scores indicating more hostility. | Posted | Mean | Standard Deviation | score on a scale | The assessment was completed 30 minutes after completion of the active/sham stimulation |
|
|
|
|
| 0 |
| 50 |
| 0 |
| 50 |
| 0 |
| 50 |
| EG001 | Sham Visit | Sham tDCS (40 minutes; divided into two 20-minutes sessions) followed by behavioral testing | 0 | 50 | 0 | 50 | 0 | 50 |
Not provided
Not provided
| D004191 | Behavioral Disciplines and Activities |
| D004597 | Electroshock |
| D011580 | Psychological Techniques |
|
| AIHQ (aggression) |
|