Cognitive Remediation Therapy for Schizophrenia: Effects on EEG and Emotional Regulation

This is a randomized controlled trial examining the effects of Cognitive Remediation Therapy (CRT) on neurophysiological and behavioral outcomes in schizophrenia. The primary goal is to assess whether CRT improves attentional control, sensory processing, executive function, and emotional regulation as measured by EEG and GSR.

Sixty participants will be enrolled: 30 individuals diagnosed with schizophrenia (DSM-5 criteria) and 30 healthy controls matched by age and gender. The schizophrenia group will be randomized into a CRT intervention arm and a waitlist control group. Healthy controls will not undergo CRT but will participate in baseline neurophysiological assessments to establish normative EEG and GSR values.

CRT will consist of 12 weekly sessions (approximately 60 minutes each), targeting cognitive domains such as working memory, attention, executive function, and emotion regulation using structured exercises and computer-based tasks.

EEG recordings will include P300 (oddball paradigm), mismatch negativity (MMN), and frontal theta power (cognitive control tasks). GSR will assess baseline skin conductance and reactivity to negative emotional stimuli. Behavioral tasks include the Stroop task, digit span, and facial emotion recognition.

Psychometric instruments include the Turkish-validated versions of:

• Difficulties in Emotion Regulation Scale (DERS)
• Brief Assessment of Cognition in Schizophrenia (BACS)
• Schizophrenia Quality of Life Scale (SQLS)

Primary outcomes will be assessed via pre- and post-test comparisons. Statistical methods include repeated-measures ANOVA, mixed-effects modeling, and regression analyses linking physiological changes to cognitive and emotional performance.

The study is ethically approved and aligns with international standards for human research.

Inclusion criteria

(Schizophrenia Group):

• Diagnosed with schizophrenia according to DSM-5 criteria
• Age between 18 and 55 years
• Clinically stable (no hospitalization or medication change within 1 month)
• Minimum primary school education
• Able to provide informed consent
• Right-handed (for EEG protocol consistency)

Inclusion criteria

(Healthy Control Group):

• No history of psychiatric or neurological disorders
• Age- and gender-matched to schizophrenia group
• No current medication affecting CNS
• Able to provide informed consent
• Right-handed

Exclusion criteria

(Both Groups):

• Current or past substance use disorder (within the past year)
• Comorbid neurological illness (e.g., epilepsy, traumatic brain injury)
• Current use of benzodiazepines or medications that significantly affect cognitive function
• Intellectual disability or MoCA score < 20
• Visual or hearing impairments that could interfere with task performance
• Participation in a psychological intervention in the last 3 months