Inclusion Criteria:

• Schizophrenia

• Participants will be included if they:

  1. Are voluntary and competent to consent;
  2. Have a diagnosis of Schizophrenia or Schizoaffective Disorder as confirmed by the Structure Clinical Interview for the DSM-IV (SCID-IV)
  3. Have persistent positive and negative symptoms despite having trialled, or being currently medicated, with antipsychotic medication; and
  4. are between the ages of 18 and 65.

• Concomitant medications including:

  1. Benzodiazepines,
  2. Mood stabilizers (lithium, valproic acid)
  3. Antidepressants (including serotonin reuptake inhibitors and tricyclic antidepressants) and anticholinergics will be allowed. Since carbamazepine has been shown to interfere with the effects of anodal tDCS, potential participants taking it will not be suitable for inclusion in the trial.
• Depression

• Participants will be included if they:

  1. Are competent to consent;
  2. Have a diagnosis of Major Depression and are currently experiencing a Major Depressive Episode as confirmed by the Structure Clinical Interview for the DSM-IV (SCID-IV);
  3. Are treatment resistant, defined as a failure to achieve a clinical response, or an inability to tolerate, an antidepressant trial of sufficient dose for at least 6 weeks; and
  4. Are between the ages of 18 and 75.

• Concomitant medications including:

  1. Benzodiazepines,
  2. Mood stabilizers (lithium, valproic acid)
  3. Antidepressants (including serotonin reuptake inhibitors and tricyclic antidepressants) and anticholinergics will be allowed. Since carbamazepine has been shown to interfere with the effects of anodal tDCS, potential participants taking it will not be suitable for inclusion in the trial.

Exclusion Criteria:

• Patients will be excluded if they:

  1. Have a DSM-IV history of substance abuse or dependence in the last 6 months;
  2. Have a concomitant major and unstable medical or neurologic illness;
  3. Are currently taking carbamazepine; or,
  4. Are pregnant.

• Patients will be withdrawn from the study if they:

  1. Withdraw consent;
  2. Experience significant clinical deterioration;
  3. Fail to tolerate the procedure; or,
  4. Develop a serious adverse event. In the event that a patient is withdrawn or drops out of the study, efforts will be made to obtain a final set of clinical, cognitive and neurophysiological measures at the time of withdrawal for a last observation carried forward analysis.