Guided imagery reduces stress by effecting the part of the brain that is responsible for processing imagery. This in turn releases brain chemicals that act as the body's natural brain tranquilizers, lowering blood pressure, heart rate, and anxiety levels.

Researchers at Ohio State University reported that people with cancer who used imagery while receiving chemotherapy felt more relaxed, better prepared for their treatment and more positive than those who used placebo.

A study at Southeastern Louisiana University found that the use of with guided imagery demonstrated significantly less state anxiety, lower cortisol levels one day following surgery, and less surgical wound problems than the control group. The researchers concluded that guided imagery demonstrated stress-relieving outcomes closely associated with healing.

In other research, scientists at the Center for Stress Management in North Carolina examined the effects of mental imagery on the immune system response, and specifically, on depressed white blood cell (WBC) counts. Results indicated significant increases in WBC count for all patients over a 90-day period, even when possessing disease and illnesses that would have predicted a decrease in WBC count.

A group of researchers at Hadassah University Hospital in Israel examined the long-term effects of relaxation and guided imagery on patients recently diagnosed with cancer. Results showed a decrease in psychological distress and an increase in the patient's sense of internal control.

Depending on the combination of guided imagery techniques used, therapeutic approach, and the client’s stress level, most people experience positive changes due to a reduction in biases or distortions in thinking, resulting in more effective functioning.

References
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