A good question with lots of history to it. There is a great website now that is organizing research on the psychology of atheism (including mental health). THe research being done by those researchers (which includes one of the doc students in my PhD training program) is a needed corrective to the past research that has tended to misunderstand important elements of atheism and how that should be assessed and explored in people's lives. You can find great info here: http://www.atheistresearch.org/

Of course, there is a HUGE literature (mostly from the US) that shows that people who are religious (again, mostly Christian people in the US) experience many mental and physical health benefits. The most impressive finding is that religious service attendance is related to lower mortality rate even after controlling for many factors such as drinking, smoking, physical disease, etc. There are other relationships between religion and health supported by the research as well (see Powell, Shahabi, & Thoresen, 2003 American Psychologist, Vol 58, no. 1).

The comment about Ellis is an interesting one and I think wikipedia is too kind to him. Ellis certainly made wonderful contributions to the science and practice of psychology. However, he missed the boat on religion in many ways. His early comments about religion are not based in empirical research, but more his own biases as an atheist. When the article says he "acknowledged and agreed with survey evidence" that is a very kind way of saying that in 2000 (in a Professional Psychology: Research and Practice article) he recanted much of what he had adamantly stated about religion in the past, stating that religion might be helpful in some instances. Of course, serious psychologists of religion had been stating that and providing supporting research, for about 2 decades prior to that.

As to your specific question of growth and irrationality related to religion or atheism, I tend to see devout religionists and strict atheist as representing two important elements of being human. To me, we need hope faith and maybe some irrationality. But certainly we need rationality, critical thinking, and an existentialists' courage to face what really is. To disregard either in the name of the other is a sign of getting stuck in one's personal growth (although at times in one's development focusing on one more than another seems appropriate also). There are important psychological reasons why religious and spiritual faith has persisted despite Freud's (and Ellis') claims that religion is somehow a less fully developed stage in humanity. I am not sure what all those reasons are, but I believe they are important and will likely stand the test of time.

A good question with lots of history to it. There is a great website now that is organizing research on the psychology of atheism (including mental health). THe research being done by those researchers (which includes one of the doc students in my PhD training program) is a needed corrective to the past research that has tended to misunderstand important elements of atheism and how that should be assessed and explored in people's lives. You can find great info here: http://www.atheistresearch.org/

Of course, there is a HUGE literature (mostly from the US) that shows that people who are religious (again, mostly Christian people in the US) experience many mental and physical health benefits. The most impressive finding is that religious service attendance is related to lower mortality rate even after controlling for many factors such as drinking, smoking, physical disease, etc. There are other relationships between religion and health supported by the research as well (see Powell, Shahabi, & Thoresen, 2003 American Psychologist, Vol 58, no. 1).

The comment about Ellis is an interesting one and I think wikipedia is too kind to him. Ellis certainly made wonderful contributions to the science and practice of psychology. However, he missed the boat on religion in many ways. His early comments about religion are not based in empirical research, but more his own biases as an atheist. When the article says he "acknowledged and agreed with survey evidence" that is a very kind way of saying that in 2000 (in a Professional Psychology: Research and Practice article) he recanted much of what he had adamantly stated about religion in the past, stating that religion might be helpful in some instances. Of course, serious psychologists of religion had been stating that and providing supporting research, for about 2 decades prior to that.

As to your specific question of growth and irrationality related to religion or atheism, I tend to see devout religionists and strict atheist as representing two important elements of being human. To me, we need hope faith and maybe some irrationality. But certainly we need rationality, critical thinking, and an existentialists' courage to face what really is. To disregard either in the name of the other is a sign of getting stuck in one's personal growth (although at times in one's development focusing on one more than another seems appropriate also). There are important psychological reasons why religious and spiritual faith has persisted despite Freud's (and Ellis') claims that religion is somehow a less fully developed stage in humanity. I am not sure what all those reasons are, but I believe they are important and will likely stand the test of time.

I do not believe in atheism as origin of (mental) health. However, we found a correlation between conversion disorder (dissociative aphonia and dissociative blindness) in cases of religeous conversion. The most famous example, I suppose, is the conversion of St. Paul ("Damascus event"). That means probably, you may change your mind and belief, but you need another one. Most people are no religeous leaders, but they cannot tolerate atheism. You agree?

Perhaps being agnostic is a choice to experience first hand rather than second hand spiritual connection and being atheist is still waiting and losing belief in a spiritual dimension. Spiritual ideology is so often at the core of a mental health crisis that there are large bodies of work on spiritual emergence becoming an emergency due to societies non acceptance and poor handling of it.

Abraham Maslow wrote a wonderful little book called 'Religions, Values and Peak experiences' 1964. He explains that the peak experience of expanded awareness and connection to ones humanity and spirituality can be seen as religious raptures in a religious context but it can also be seen as a mental health issue when not contained in a religious context. Also that the peak experiences of enlightened masters are then protected by their followers, non-peakers, who make sure no one else gets to have this experience as it threatens their belief that its not a normal human experience available to everyone.

I would add that when you look at the financial profits organized religion generates it would also be very keen to keep the average person from having their own peak experience and that psychiatry is now the gate keeper replacing the witch hunters of old. One would have to question if Jesus would have got through his 40 days in the desert battling demons, or Buddha his 3 years in a jungle cave eating berries, if a psychiatrist was present. This is true of many great poets, artists, writers, inventors and of course all Shamanic healers going back in human history to the beginning.

Stanlov Grof conducted experiments with his wife whereby she was allowed to be psychotic without intervention. She was given safety, food and liquids and in time she would unravel then reorder to emerge stronger that before. This is being repeated now in Iceland with the Open Dialogue work of no diagnosis and no drugs. Their outcomes have gone from one of the worst in the world to one of the best. Most importantly the experience of psychosis is individual and due to fear and a desire to alleviate perceived suffering is usually interrupted and suppressed.

Actually, spirituality and religiosity have been documented in the empirical literature as protective factors in epidemiologic studies of mood disorders. The work of Columbia psychologist Lisa Miller in conjunction with Myrna Weissman's research group have produced a number of papers on this. See the following reference in pubmed: http://www.ncbi.nlm.nih.gov/pubmed/21865527

Maybe you can use the statistic of Czech Republic to compare, if the prevalence of mental disease is different here from less atheistic countries. In Czech Republic about 68% of the population declare, that they are ateistic or have no special religion.

One possible source: http://www.uzis.cz/en/catalogue/psychiatric-care