Sunday, July 22, 2012

Belief in God leads to brain damage

Yes, that is an actual conclusion of a scientific study conducted at the Center for the Study of Aging and Human Development, Duke University Medical Center, Durham, North Carolina. Researchers Amy D. Owen, et. al., studied neuroimaging data from MRI measurements to assess the relationship between religious factors and structural neuroanatomy, specifically hippocampus volume in the brain. The hippocampus has been associated with memory consolidation, learning and influencing of emotions via connections with the amygdala. Atrophy of this brain structure later in life has been associated with dementia, Alzheimer’s disease, depression and lessened ability to form new memories. The study found that people who reported having a life-changing religious experience showed increased hippocampal atrophy from base line to final assessment among born-again Protestants, Catholics, and those with no religious affiliation.

Participants in the study, conducted between 1994 and 2005, were 268 men and women over the age of 58. Religious factors assessed included frequency of public worship, private activity (prayer, meditation, or Bible study), and religious group membership. Baseline and annual factors assessed included born-again status and life-changing religious experiences. The study found that those who reported a born-again or life-changing religious experience suffered greater hippocampal atrophy during later life. The authors interpreted the findings by hypothesizing that cumulative stress, producing glucocorticoids, led to decreased hippocampus volume.

Some covariates that may impact the results were studied, including social support, self-reported stress and depression. These and other variables require more research in connection with the results found. It is questionable whether this study adequately considered other factors, such as prescription drug use, diet, exercise, non-religious life stressors, mental activity level, and so on. And, is it possible the causal relationship is reversed? Perhaps the self-perceived effects of aging may lead one to sense his or her own mortality, leading one to more diligently seek a religious experience. Causal relationships between brain anatomy and emotional/psychological factors are always tenable at best.

The study speculated that stress may be present for born-again Christians as a result of being a religious minority. However, that conclusion seems unfounded because most of the demographic sample included Southeastern Protestant Christians, hardly an oppressed minority in that part of the USA. The researchers' primary premise seems accurate (though not the secondary conclusion), that stress-induced cortisol in the body can affect the hippocampus, and is supported by other research. In particular, returning Gulf War veterans suffering from chronic PTSD exhibited smaller hippocampal brain regions in MRI exams than a control group. An additional interesting finding is that therapeutic treatment seems to be associated with an increased hippocampal volume after six months, indicating a resilience.[2] Perhaps born again Christians can be treated? The secondary conclusion, that people with a life-changing religious experience suffer more stress, seems irrational, particularly in light of other studies that indicate positive emotional and psychological benefits of religious experiences.

A few points need to be made here. First, if the hypothesis of the researchers is accurate – that increased stress leads to increased glucocorticoids, thereby damaging the hippocampus – would it not seem reasonable that people who have had a life-changing religious experience would experience less stress? Almost by definition, an experience that is life changing would seem to bring more peace and contentment to one’s life. How would a life-changing religious experience lead to more stress? The researchers own hypothesis seems to be contradicted by the results of the study.

Second, since millions – perhaps billions – of people throughout history, across all cultures, claim to have strong religious beliefs, does this study conclude they were also brain-damaged? It is a well-known fact that many people from all races and geographical locations through all of recorded human history have believed in some deity, afterlife, and/or spiritual experience. Not all of these are of the evangelical Christian variety. The bias of this study is striking – the group studied were Christians, not Hindus, Muslims, or Rastafarians. The control group – those supposedly with normal cognitive anatomy – were those with no religious affiliation.

Third, other studies have found there is not necessarily the supposed direct connection with hippocampal size and mental function, such as memory. In the December 22, 2011 issue in the journal Neuron, Dr. Jordan Poppenk, Baycrest's Rotman Research Institute, found some evidence that extensive spatial memory acquisition leads to enlargement of the posterior hippocampus and a decrease in the anterior hippocampus. In other words, there may not be a direct one-to-one relationship between size and memory capabilities. Poppenk stated, "This suggested to us that the crucial predictor of individual differences in recollection ability might not be the overall size of the hippocampus but the separate contributions of the posterior and anterior segments of the hippocampus." [3]

In conclusion, much evidence links religious and spiritual involvement with improved mental health. [4] And, a study conducted of more than 20,000 adults representative of the U. S. population found that an average life expectancy difference of seven years for those who attend church or religious services over those who do not. [5] Perhaps, during those seven years, they were brain damaged as well.

[1] Owen AD, Hayward RD, Koenig HG, Steffens DC, Payne ME (2011) Religious Factors and Hippocampal Atrophy in Late Life. PLoS ONE 6(3): e17006.doi:10.1371/journal.pone.0017006.
[2] Brigitte A. Apfel, Jessica Ross, Jennifer Hlavin, Dieter J. Meyerhoff, Thomas J. Metzler, Charles R. Marmar, Michael W. Weiner, Norbert Schuff, Thomas C. Neylan.Hippocampal Volume Differences in Gulf War Veterans with Current Versus Lifetime Posttraumatic Stress Disorder Symptoms. Biological Psychiatry, 2011; 69 (6): 541 DOI: 10.1016/j.biopsych.2010.09.044
[3] Cell Press, “Gauging individual human memory from scans of brain’s hippocampus?” ScienceDaily, 20 Jan 2012, Web 22 Jul 2012.
[4] Raymond F. Paloutzian, et. al., Handbook Of The Psychology Of Religion And Spirituality, (New York, NY: The Guilford Press, 2005), 446.
[5] Robert A. Hummer, et. al., “Factors Affecting Mortality”, Demography, Volume 36, Number 2 (1999), 273-285, DOI: 10.2307/2648114.