Project A05 includes three 7T fMRI studies, two 3T fMRI studies and one behavioral study. Two of the 7T fMRI experiments (study 1 and 2) will be performed in the first two years of funding. The behavioral study (study 5) will start during the first year. The 3T fMRI experiments (study 3 and 4) will start in the second year. Study 3 makes use of the optimized cerebellar tDCS parameters established in the first year in A06. Study 4 will be performed in cerebellar patients. We expect data acquisition of studies 3–5 to be finished by the end of the third year. In the fourth year the tDCS set-up will be brought to the 7T MR scanner (study 6).

Guiding questions of A05:

• Does the human cerebellum, more specifically the cerebellar vermis and the fastigial nuclei, contribute to the extinction of conditioned fear?
• What are the intrinsic cerebellar mechanisms underlying extinction?
• Does the cerebellum interact with cerebral areas, in particular the amygdala, hippocampus and prefrontal cortex, during extinction?
• Do the posterolateral cerebellar hemispheres and vermis play a different role in extinction?
• Can the proposed intrinsic cerebellar mechanisms and cerebello-cerebral interactions be modulated by cerebellar transcranial direct current stimulation (tDCS) and by cerebellar dependent motor learning?