God on the Brain - questions and answers
What are the temporal lobes of the brain?
The temporal lobe controls hearing, speech and memory. The brain has two temporal lobes, one on each side of the brain, located near the ears. The two are interchangeable so if one is damaged the other is usually able to take over the other's function.
What is temporal lobe epilepsy?
It is a condition in which the patient suffers repeated seizures when there is abnormal electrical activity in the temporal lobes of the brain. These seizures may be simple partial seizures without loss of awareness or they can be complex partial seizures with loss of awareness. The patient loses awareness during a complex partial seizure because the seizure spreads to both lobes, causing memory loss. The condition was first recognised in 1881.
What percentage of patients with temporal lobe epilepsy suffer from religious hallucinations?
It is difficult to say because unless the doctor brings up the subject directly with the patient, they may never know if the patient has religious hallucinations. Estimates vary between 10 and 70% , but most neurologists believe only a minority of patients with temporal lobe epilepsy suffer from hallucinations.
Are scientists arguing that all religious experiences can be related to temporal lobe epilepsy?
Not at all. While studies have clearly shown a relationship between religious experience and temporal lobe epilepsy. This does not explain all religious experience by any means. Religious and spiritual experiences are highly complex, involving emotions, thoughts, sensations and behaviours. But scientists do believe that patients with temporal lobe epilepsy, who experience religious hallucinations may provide a valuable model in showing how certain types of religious experience effect the human brain.
Does this work suggest there is a specific 'god spot' in the brain?
Although the temporal lobes are clearly important in religious experience, they are not the whole story. Already the work of Dr Andrew Newberg has shown that a part of the brain called parietal lobes are important. Additionally, very different patterns of brain activity may appear, depending on the particular experience the individual is having. For example, a near death experience might result in different activity patterns from those found in a person who is meditating. Scientists now believe that a number of structures in the brain need to work together to help us experience spirituality and religion.
Are we 'hardwired' for god?
The term 'hardwired' suggests that we were purposefully designed that way. Neuroscience can't answer that question. However what it can say is that the brain does seem to predisposed towards a belief in spiritual and religious matters. The big mystery is how and why this came about.
How does Dr Persinger induce artificially religious experiences in his patients?
Dr Persinger has designed a helmet that produces a very weak rotating magnetic field of between ten nanotesla and one microtesla over the temporal lobes of the brain. This is placed on the subject's head and they are placed in a quiet chamber while blindfolded. So that there is no risk of 'suggestion', the only information that the subjects are given is that they are going in for a relaxation experiment. Neither the subject nor the experimenter carrying out the test has any idea of the true purpose of the experiment. In addition to this, the experiment is also run with the field switched both off and on. This procedure Dr Persinger claims will induce an experience in over 80% of test subjects.
What sort of experiences do subjects report?
This is very dependent on the belief system of the individual subjects. Dr Persinger talks about his subjects feeling a 'sensed presence' - feeling that somebody was in the chamber with them. Subjects who are strongly religious are likely to interpret this presence as god. Whereas, atheists may also report a 'sensed presence' but attribute the phenomena to a trick of brain chemistry, perhaps comparable to when they have taken drugs in the past.
Could it be there is a genetic component to religious belief?
Religious behaviour is so complex it is very unlikely that there will be a single gene for religious activity, but it does seem as if there is some sort of as yet unidentified genetic component. Several studies of identical twins separated at birth and brought up separately have measured religiosity. Religiosity is defined as the intensity of religious belief. These studies have shown that there appears to be about a 50% component to religiosity.
Clearly, what religion you are brought up in is largely dependent upon the culture into which you are born, but what appears to have a significant genetic component is your level of religious intensity.
Will any of this research ever be able to establish whether god exists or not?
Whether god exists or not is something that neuroscience cannot answer. For example, if we take a brain image of a person when they are looking at a picture, we will see various parts of the brain being activated, such as the visual cortex. But the brain image cannot tell us whether or not there is actually a picture 'out there' or whether the person is creating the picture in their own mind. To a certain degree, we all create our own sense of reality. Getting to what is real is the tricky part.