Читать книгу Abnormal Psychology - William J. Ray - Страница 114

The case study is one of the most widely used methods for studying individual participants. It is based on the logic of describing, analyzing, interpreting, and evaluating a set of events and relationships within a framework or theory (Bromley, 1986). The typical descriptive case study focuses on either problematic or exceptional behaviors of one individual. Indeed, for years the case study approach has been the primary method for studying phenomena in clinical medicine, clinical psychology, and the neurosciences. It has a particularly important history in the study of mental disorders.

case study: a research method that typically focuses on recording the experiences and behaviors of one individual

The case study method has a rich tradition in studying unique situations that do not lend themselves to traditional experimental procedures. Much of our initial understanding of brain function came from careful study of individuals who had had accidents or experienced war injuries. With psychopathology, the case study offers a means of examining in some depth the manner in which a person understands and experiences his or her disorder. Further, the case study offers a means of helping researchers develop new questions to be asked concerning a disorder in terms of how it developed and might be treated.

In psychopathology research, the advantage of the case study is its ability to present the clinical implications of a particular disorder. One classic example that Freud discussed was the case study of Anna O., which I will introduce in Chapter 9. Another example is described in Morton Prince’s book The Dissociation of a Personality (1913). Prince described a case of multiple personality (now called dissociative identity disorder) at a time when the existence of that diagnostic category was in question.

An advantage of such extended discussions in a case study is the ability to describe processes not easily reduced to a single variable. For example, Luria (1972) described in great detail the attempt of one man to overcome a neuropsychological deficit that left him with “a shattered world.” This is a story about a brilliant young Russian scientist, Zasetsky, who became a soldier in World War II and was shot in the head. Zasetsky’s wound was such that areas of the brain that help one move in space or understand complex language were damaged, whereas areas that allow one to reflect on one’s condition were not. Luria’s intriguing work describes both his and the patient’s own experiences over a 25-year period. Initial case studies from battlefield experiences also helped to clarify the nature of post-traumatic stress disorder (PTSD), which will be discussed in Chapter 7.

Another famous case study in the history of neuropsychology is that of Phineas Gage. In 1848, Phineas Gage was a railroad construction supervisor in Vermont. Part of his job was to prepare the charges to blast rocks so that the railroad tracks could be laid. To do this, a hole would be drilled in the rock and then gunpowder would be placed in the hole followed by sand. This would then be tamped down with a long iron rod. On September 13, 1848, Gage did not realize that the sand had not been added and began to drop the iron rod into the hole. As the rod went into the rock, a spark ignited the gunpowder and the 13-pound iron rod shot out and through Gage’s brain, as shown in Figure 3.1, and landed some 30 feet away (Damasio, Grabowski, Frank, Galaburda, & Damasio, 1994).

Phineas Gage after the accident.

Public domain

Amazingly, after being momentarily stunned, Gage regained full consciousness and was able to talk and to walk with help. He was taken back to his boardinghouse and seen by a local doctor. What was surprising was that, over time, Phineas Gage was able to recover from his physical injuries. He continued to be able to speak and perform the everyday motor processes required. His intelligence and ability to learn new information remained as before the accident. However, his personality showed such a drastic change that his coworkers said he was “no longer Gage.” Whereas he had been a mild-mannered person before the accident, afterward he was prone to angry outbursts. Gage also lacked social conventions after the accident and frequently used profanity. The accident had influenced his emotional processing. This case study, as described by his physician, Dr. Harlow, has helped scientists understand the manner in which brain damage can influence social and emotional processes seen in other types of mental disorder. This helped later scientists consider which areas of the brain might be involved in mental disorders that show deficits in social and emotional processing. The iron rod and Gage’s skull have been retained in a museum at Harvard University.

Figure 3.1 Depiction of the Rod in Phineas Gage’s Brain

Source: H. Damasio, T. J. Grabowski, R. J. Frank, A. M. Galaburda, & A. R. Damasio, “The Return of Phineas Gage: Clues About the Brain from the Skull of a Famous Patient,” Science, Vol 264, 20 May 1994. Reprinted with permission from the American Association for the Advancement of Science (AAAS).

Modern researchers have sought to use the case of Phineas Gage to illustrate types of brain damage. Hanna Damasio and her colleagues (1994), using photographs and X-rays of the skull, created a three-dimensional reconstruction including the entry and exit points of the iron rod. From this, they described the suggested damage to the left and right prefrontal cortex, which would include a lack of inhibition as shown by his angry outbursts, a lack of planning, memory problems, and deficits in social cognition. Peter Ratiu and his colleagues (Ratiu, Talos, Haker, Lieberman, & Evert, 2004) performed computerized axial tomography (CAT) scans on the skull of Phineas Gage to determine the manner in which the rod was projected through his skull. Using these same CAT scans, John Van Horn and his colleagues (2012) sought to model damage to the white and gray matter of the brain. In order to estimate the damage to Gage’s brain, these researchers examined the white matter connections of 110 healthy male individuals 25 to 36 years of age using brain imaging techniques. They suggested that Gage suffered from damage to the left frontal cortex and that impairment to network connectedness between the left frontal area and other brain areas would have been considerable. This modeling is shown in Figure 3.2.

Figure 3.2 Three-Dimensional Reconstruction of the Rod

Source: Van Horn et al. (2012).

The basis of every case study is the clinical notes of the professionals. Diagnosis and treatment notes are kept for each individual these professionals see. The case study offers an opportunity for an in-depth examination of an individual’s manifestation and experience of psychopathology. It is particularly important for the description of rarer conditions in which the salient factors are not yet well understood. However, it is difficult to know from a case study whether the relationships described were unique to that individual or could be generalized to others with the disorder. As such, it is perhaps most useful for directing future research concerning the critical variables involved in the disorder.