NCT05746494

The Efficacy of Neural Stimulation in Individuals With Schizophrenia

Completed NA Results posted Last updated 26 February 2025

What this trial tests

NA trial testing tDCS in Schizophrenia in 50 participants. Completed in 1 August 2024.

Timeline

21 November 2022

Primary endpoint
1 August 2024

1 August 2024

Quick facts

Lead sponsor	The University of Texas at Dallas
Phase	NA
Status	Completed
Study type	INTERVENTIONAL
Allocation	randomized
Design	crossover
Masking	double
Primary purpose	basic science
Enrollment	50
Start date	21 November 2022
Primary completion	1 August 2024
Estimated completion	1 August 2024
Sites	1 location across United States

Drugs / interventions tested

• tDCS — full drug profile →

Conditions studied

• Schizophrenia — all drugs for Schizophrenia →
• Schizo Affective Disorder — all drugs for Schizo Affective Disorder →

Sponsor

The University of Texas at Dallas

Who can join

Adults 18 to 64, any sex, with Schizophrenia or Schizo Affective Disorder. Patients with the condition only — healthy volunteers not accepted.

Results — posted to ClinicalTrials.gov

Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.

The State Social Paranoia Scale (SSPS) Primary · The assessment was completed before the stimulation and 30 minutes after completion of the active/sham stimulation

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.

Group	Value	95% CI
Active Visit	9.72	± 14.61
Sham Visit	3.90	± 11.56

Ecological Momentary Assessment (EMA)-Based Paranoia Primary · 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)

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.

Group	Value	95% CI
EMA-baseline	3.78	± 1.72
EMA-active	3.61	± 0.91
EMA-sham	3.96	± 1.85

Birchwood Social Functioning Scale (SFS) Primary · The assessment was completed 30 minutes after completion of the active/sham stimulation

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).

Group	Value	95% CI
Active Visit	114.21	± 22.35
Sham Visit	114.59	± 27.54

Ecological Momentary Assessment (EMA)-Based Social Functioning Primary · 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)

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).

Social interaction frequency

Group	Value	95% CI
EMA-baseline	0.97	± 0.76
EMA-active	0.91	± 0.83
EMA-sham	0.92	± 0.90

Social interaction motivation and experience

Group	Value	95% CI
EMA-baseline	3.74	± 1.62
EMA-active	4.08	± 1.68
EMA-sham	3.71	± 1.62

The Trustworthiness Task Secondary · The assessment was completed 30 minutes after completion of the active/sham stimulation

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.

Group	Value	95% CI
Active Visit	0.07	± 1.16
Sham Visit	-0.18	± 0.99

The Scrambled-sentences Task (SST) Secondary · The assessment was completed 30 minutes after completion of the active/sham stimulation

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).

Group	Value	95% CI
Active Visit	0.46	± 0.29
Sham Visit	0.49	± 0.28

The Ambiguous Intentions Hostility Questionnaire (AIHQ) Secondary · The assessment was completed 30 minutes after completion of the active/sham stimulation

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).

AIHQ (blame)

Group	Value	95% CI
Active Visit	8.28	± 3.07
Sham Visit	8.89	± 3.22

AIHQ (hostility)

Group	Value	95% CI
Active Visit	2.09	± 0.75
Sham Visit	2.35	± 0.78

AIHQ (aggression)

Group	Value	95% CI
Active Visit	1.75	± 0.40
Sham Visit	1.78	± 0.39

The Hostility Scale of the Personality Inventory for DSM-5 (PID-5-HS) Secondary · The assessment was completed 30 minutes after completion of the active/sham stimulation

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.

Group	Value	95% CI
Active Visit	9.42	± 7.56
Sham Visit	11.30	± 7.57

Sponsor's own description

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.

Publications & conference data

1 peer-reviewed publication reference this trial (live from Europe PMC):

1. Transcranial Direct Current Stimulation Improves Paranoia and Social Functioning in Schizophrenia: A Randomized Clinical Trial.
   Fan L, Carrico S, Zhu Y, Ackerman RA, et al · · 2025 · cited 2× · PMID 39855408 · DOI 10.1016/j.biopsych.2025.01.011