Weekly individual psychotherapy targeting specific maintenance factors of paranoia (worry, anomalous experiences, self-confidence, and safety behaviors), tailored to the participant's experience

Participants will continue with their regular care (treatment as usual (TAU)) without interference from the study team. In addition to TAU, a study therapist will call them weekly to review what treatment the participants have engaged in. Phone calls will last approximately 5-10 minutes

Individuals will be assessed for which psychological factors are maintaining paranoia in their daily lives. They will collaboratively identify one maintenance factor to focus on (e.g. worry, anomalous experience, self-confidence, PTSD) for 8 weeks of individual therapy. Then, all participants will transition to 8 weeks of individual therapy focused on dropping safety behaviors and re-engaging in everyday life.

Reversal learning data will be collected from a 3-option probabilistic reversal learning task. This data will be analyzed using a computational model that estimates the prior expectations of environmental volatility. That parameter, in many models, is Mu3.

Reversal learning data will be collected from a 3-option probabilistic reversal learning task. This data will be analyzed using a computational model that estimates the unexpected uncertainty, sometimes also referred to as sensitivity to volatility.

The PSYRATS is a interview-assisted assessment measuring the severity of a delusional belief. Total scores range from 0-24 with high scores indicating more severe delusion; 6 questions, 0-4 scale for each item

The PANSS is a 30-item clinician-rated instrument for assessing schizophrenia symptoms. It consists of 3 subscales: positive subscale (7 items), negative subscale (7 items), and general psychopathology subscale (16 items). For each item, symptom severity was rated on a 7-point scale, from 1=absent to 7=extreme. The PANSS total score for each participant was sum of the rating assigned to each of the 30 PANSS items, and ranged from 30 to 210 with a higher score indicating greater severity of symptoms. The positive symptom total score is the sum of the Positive Symptom items

functional MRI will be used to collect BOLD activation data during the PRL reversal learning task. The investigators expect changes in activation following treatment, particularly in the CBTp group

The PANSS is a 30-item clinician-rated instrument for assessing schizophrenia symptoms. It consists of 3 subscales: positive subscale (7 items), negative subscale (7 items), and general psychopathology subscale (16 items). For each item, symptom severity was rated on a 7-point scale, from 1=absent to 7=extreme. The PANSS total score for each participant was sum of the rating assigned to each of the 30 PANSS items, and ranged from 30 to 210 with a higher score indicating greater severity of symptoms. P1 is the first item on the scale, representing delusion severity