Forty-eight people diagnosed with social phobia in an experimental study that randomized into two treatment groups: 1) Internet-based Cognitive Behavioural Therapy (iCBT) (n = 24) or 2) computerized attention training (n = 24). After nine weeks we change the condition of the two groups of research participants, which should therefore be given both treatments. Pre-and post measurement of functional magnetic resonance imaging (fMRI) will take place in the first round of treatment. Genotyping based on saliva samples takes place before the start of treatment, at the first fMRI measurement, for those who voluntarily leave the sample.

Study hypothesis

How is the brain activity of emotional processing and anxiety affected after completing an Internet-based CBT compared with computerized attention training? Does the treatment response of an Internet based treatment affects by variations in serotonin-transporter-linked promoter region (5-HTTLPR) and tryptophan hydroxylase-3 (TPH3) genes?

How is the genetic variations related to symptoms in social phobia (pre treatment)?

Inclusion Criteria:

• Participants must meet criteria for social phobia using the International classification system Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV).

Exclusion Criteria:

• Individuals with current depression and/or is suicide prone will be excluded from the study.
• With fMRI the following criteria must not be filled: previous surgery in the heart or brain, metals implanted in the body, dental braces or bridge; piercings that can´t be taken out, tattoos (shoulders, arms and back is not so good, the legs are okay if it is not too large); trouble to lie still for about an hour, pregnancy or history of neurological diseases.