a relatively uneventful life. Studies have shown that such substantial differences between siblings who begin life with identical information encoded in their genes are not uncommon.25
Contemporaneous with this research, a new set of studies began to challenge the prevailing view of the tractability of psychological conditions through which stress manifests. PTSD, for instance, has been viewed as “a chronic and recurring condition” in review articles.26 Another review of an aggressive PTSD treatment regime found that “the treatment program’s impact on the course of illness had been negligible”.27,28 Anxiety and depression, though treatable, also usually persist for extended durations.29
Figure 2. Divergence of gene expression as identical twins age. The yellow areas are common to both. The chromosomes on the left are at the age of 3; those on the right, 50.
Figure 3. Fifty-year-old monozygotic twins show marked external physiological differences.
Table 1: The reduction of psychological symptoms in EFT studies (Italics indicates a randomized controlled trial).
Abbreviations: SAS Speaker Anxiety Scale. TAI Test Anxiety Inventory. SA-45 Symptom Assessment-45. HADS Hospital Anxiety & Depression Scale. BDI Beck Depression Inventory. IES Impact of Events Scale. SUD Subjective Units of Distress. CROPS Child Report of PTSD Symptoms. PCL-M PTSD Checklist-Military
Using a novel behavioral intervention called Emotional Freedom Techniques (EFT), researchers have recently shown that chronic clinical PTSD can be remediated in 86% of patients in just six sessions, with gains being reliably maintained on follow-up (p < .0001). Similar studies of EFT and PTSD followed subjects for up to a year and found that the effects held over time.30,31 EFT was likewise found to resolve phobias in a single session.32,33 It was equally effective in very limited treatment time frames for depression and anxiety.34-36 A randomized controlled trial delivering EFT over the internet found a significant improvement in fibromyalgia symptoms.37 Other studies showed immediate reductions in pain when emotional memories were treated.38 Evidence for a rapid reduction in the primary stress hormone cortisol after EFT administration has been noted,39 and reviewing the published research on the epigenetic effects of EFT and similar interventions traces the mechanisms of action by which these techniques affect genetic, hormonal, and neurological processes, including methylation and acetylization of stress genes.40 These studies show that stress-related psychological conditions and emotional traumas may be successfully treated in time frames that are small fractions of those required by earlier forms of therapy.
CONCLUDING REMARKS
Taken together, these studies indicate that:
•Emotional states are epigenetic – they regulate gene expression.
•Stress can produce large differences in telomere length by age 40.
•When emotional states are improved by the acquisition of stress-reduction skills, beneficial changes in gene expression are found.
•Stressful emotional states may be changed rapidly.
•The genes affected by emotional change are important to health and aging, governing such cellular functions as programmed regeneration, free radical scavenging, inflammation, and immune function.
The next generation of research is expected to identify a subset of genes most reliably associated with changes in emotional state, rather than requiring a whole-genome assay of all 23,688 genes. Such a subset (possibly fewer than 50 genes) has the potential to allow the biological diagnosis of psychological problems such as PTSD, depression, and anxiety. It will also permit the biological assessment of the effects of behavioral interventions such as the Relaxation Response, meditation, yoga, and EFT, permitting the rapid evolution of effective, non-invasive, and patient-oriented treatment plans. As behavioral epigenetics takes root in primary care, patients and healthcare providers will increasingly recognize that DNA is not destiny, and they will utilize emotional stress reduction as a potent medical and anti-aging intervention.
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