**1. Neural parameters of therapeutic change**

Mechanisms of neuroplasticity constitute fundamental processes behind learning and memory, that determine the ability of neuronal systems to incorporate novel environmental stimuli and to make appropriate adaptive response. Delineating cerebral processes of recovery from an insult to the brain holds promise for developing more refined and novel treatment modalities to target specific areas of pathology. Functional neuroimaging studies provide a mean to characterize changes in brain function related to psychiatric interventions. Well-established in indexing biomarkers of psychiatric disorders, novel neuroimaging techniques are now used to depict patterns of neural plasticity mediating post-treatment amelioration of symptoms. Various modalities provide indices of brain activity by measuring cerebral blood flow or glucose metabolism including functional magnetic resonance imaging (fMRI), 18fluorodeoxyglucose positron emission tomography (FDG-PET), and 99mtechnetium hexamethylpropyleneamineoxime single photon emission computed tomography (99mTc-HMPAO SPECT) [see ref. 1 for a detailed review] One powerful imaging modality that has significantly advanced our knowledge in this field is the task-based functional magnetic resonance imaging (t-fMRI).

It consists of a paradigm defined by a functional measurement including a stimulation adjusted to the brain area under investigation. The subject is required to perform a defined motor or sensorimotor, language or another cognitive or visual tasks in the MRI scanner while typically GRE T2\*-weighed echo planner images (EDI) are rapidly acquired [for a more in-depth description of fMRI see ref. 1]. Local changes in cerebral blood flow (CBF) during task execution relative to resting state are used to infer brain regions/networks functionally involved in specific tasks. To ultimately determine the specificity and amount of therapy-induced neuroplasticity, multiple pre-, and post- therapy scans are compared against activity pattern changes in other active treatment groups and a no-treatment waiting-list group [2]. With this in mind, the next section follows with an overview of main findings associated with intervention-induced neuroplasticity and their interpretations.
