Physical manifestations of Schizophrenia

Schizophrenia is a psychiatric illness characterized by disorganized thoughts, delusions and hallucinations. Emotions are also affected. They are exaggerated in some with schizophrenia, but often as not, emotions flatten. Lack of motivation and initiative, so-called poverty of thought, depression and emptiness are common symptoms of the illness. Centuries ago schizophrenia was thought to be caused by demonic possession. Through half of the last century, it was thought to be the result of poor mothering. Although psychological conflicts can exacerbate schizophrenia, the underlying causes of the illness are now known to be abnormalities in the function of the brain.

The most common treatment of schizophrenia is medication. Almost invariably, the medications act to reduce the activity of a chemical messenger in the brain called dopamine. However, while  abnormal brain chemistry is the focus of treatment, it has long been known that there are also subtle abnormalities in the structure of the brain in those who suffer schizophrenia.

Parts of the prefrontal cortex of the brain, the area responsible for organization of thought and the sense of self, are often slightly smaller in those with schizophrenia. The hippocampus and amygdala, areas associated with emotion and organization of time and space, have also been found to be diminished in size. The amounts of white matter, the connections between areas of the brain, are reduced. Conversely, the ventricles of the brain, fluid-filled hollows deep in the brain, are slightly larger in sufferers of schizophrenia. This increase in ventricular size reflects the deficits in volume of surrounding brain tissue. On the microscopic level, the brains of sufferers of schizophrenia have been found to have abnormal layers of neurons. The usual connections among brain cells may be lacking, and certain types of cells are ill-shaped, small or reduced in number. What is less appreciated, even by psychiatrists, is that the physical abnormalities of schizophrenia often extend beyond the brain itself. Minor abnormalities in physical structure can be seen in sufferers of schizophrenia — from the tops of their heads to the literal tips of their toes.

People with schizophrenia tend to have high, arched palates and narrowing and lengthening of the midfacial structures. Many, though not all, studies have found that sufferers of schizophrenia are more likely than normal individuals to exhibit hair whorls that spiral counterclockwise or appear in unexpected locations in the scalp. There are also often dermatoglyphic abnormalities in schizophrenia. Dermatoglyphics is the science of finger, palm, toe and footprint analysis. It is used primarily for identification and forensic studies. However, the science has also been used to characterize and identify various genetic and developmental disorders. Perhaps the best know example is the single transverse palmar crease, once referred to by the rather pejorative term “simian crease,” that appears in the palms of about 50% of individuals with Down Syndrome. In comparison, this crease occurs in only 3% of individuals who do not suffer Down Syndrome. One of the most reliable dermatoglyphic findings in schizophrenia is that individuals with the illness tend to have fewer ridges in their fingertip prints. There is also more asymmetry between the left and right hands in the patterns of fingerprints on respective fingers. In one curious study, women with schizophrenia were found to have more frequent mismatches between thumb and big toe print patterns. Whereas the above noted  single transverse palmar crease occurs in about 3% of those without Down Syndrome, studies reveal that approximately 5% to 15% of individuals with schizophrenia exhibit a single transverse palmar crease on at least one hand.

Other abnormalities of hands and feet are seen in unusually high frequency in schizophrenia. High nail bed plexus visibility is strongly associated with certain forms of schizophrenia. This trait appears under the magnifying glass as readily visible networks of small blood vessels in the flesh of the fingers above the fingernails. Those with schizophrenia are more likely to have crooked fingers, unusually large gaps between their first and second toes, unusually long middle toes, or webbing between toes. Individuals with schizophrenia also frequently exhibit altered 2D:4D ratios compared to healthy control populations. The 2D:4D ratio—the length of the index finger divided by the length of the ring finger—is a well-studied minor physical anomaly that serves as a marker for prenatal sex hormone exposure during early fetal development.

Does the existence of these various physical anomalies in sufferers of schizophrenia mean anything important? In terms of treating schizophrenia, they mean nothing. Moreover, these are simply tendencies. They cannot be used to either diagnose or rule out schizophrenia. However, these minor abnormalities do tell us that schizophrenia is deeply rooted in the brain and body. They also give us an indication as to when things may have begun to go askew. Facial structures, hair whorls, fingerprint, and toe print patterns are all established in the second trimester of pregnancy. This is a time during which the more complex areas of the brain are developing. Thus, it is likely that the abnormalities of schizophrenia, both in the brain and the body, first appear in the womb around this time.

However, the current understanding of the causes of schizophrenia is that the condition is polygenetic and multifactorial. That is, many different genes likely contribute to the condition and that genes alone do not determine it. Even among identical twins the concordance rate, that is likelihood of both twins suffering schizophrenia when one is diagnosed, is only about 50 percent. Thus, even identical genes and exposure to ostensibly identical conditions in the womb do not guarantee that schizophrenia will develop in both twins. Moreover, early childhood schizophrenia is extremely rare, occurring in less than 0.01% of sufferers. The illness most often appears around the age of twenty. Thus, while physical signs show that predisposing factors toward the illness are present even in fetal development, what might later trigger the onset of actual schizophrenia in some susceptible individuals but not others remains to be determined.