Category: Neuropsychology

Abstract

Neuropsychology is the applied science of brain-behavior relationships. The aim of this essay is to review in brief neuroimaging, and electrophysiological testing, besides reviewing structured and unstructured approaches in interviewing neuropsychiatric patients.

Introduction

Neuropsychology is the applied science of brain-behavior relationships; therefore, a neuropsychologist should have a working knowledge of physiology, psychology, and neurology to be able to assess, diagnose, and treat patients. Neuropsychology uses methods that assess specific anatomical locations and collections of functional systems (D’Amato and Hartlage, 2008).

Brain imaging and electrophysiological testing

Brain imaging techniques produce images for brain structure or functional activity and include many methods. Computerized axial tomography (CT scanning) images are produced by exposure to low levels of radiation passing through the head at different angles, thus, it produces slice by slice images of the brain or other CNS structures. Each image is analyzed by a computer to generate an effective compound X-ray image. Besides exposure to radiation, CT images do not effectively show the contrast in different tissues’ density, which can be enhanced by injecting a contrast medium. Thus, CT produces structural images pointing to structural brain changes useful in locating lesions but do not provide measures for functional activity (Stirling, 2002).

Magnetic resonance imaging (MRI) is more recent than CT scanning. The basic principle is exposing the hydrogen atoms present in the target organ (like the brain) to radio waves in a strong magnetic field. Minute magnetic fields resulting from spinning hydrogen atoms are measured and computer-processed to generate successive slice by slice images (in coronal, sagittal, or horizontal planes). Because the hydrogen atoms’ density varies in different brain tissues, MRI images are of higher resolution compared to CT images, with the second advantage of no exposure to radiation. Functional MRI measures brain structure and function, with the underpinning principle is active neurons need higher levels of oxygenated hemoglobin. Thus, the scanner detects the different magnetic fields resulting from different proportions of oxygenated hemoglobin in active and inactive neurons. This technique has proved efficacy in recognizing functional changes when patients undertake tests for working memory (Stirling, 2002).

Positron emission tomography (PET) uses the principle that active neurons use glucose more than inactive ones. Thus, shortly before the test, radioactively labeled glucose is injected (a radioactive marker), which can be of many depending on the half-life period or the affinity of the target tissue. The PET scanner measures gamma rays resulting from decay, thus assessing activity. PET provides color-coded images of patients’ brains as they undertake assignments, therefore it assesses functional brain activity. Other imaging techniques are regional cerebral blood flow and single-photon emission computerized tomography, which are variants of PET (Stirling, 2002).

Electrophysiological brain assessment includes EEG and recording evoked potentials, where EEG measures the pattern of the brain’s electrical activity as an ongoing brain activity. Although EEG provides a direct record of brain activity, analysis and interpretation of the record are difficult whether recorded in alert aroused state or in the awakened but relaxed state. Evoked potentials measure which parts of the cerebral cortex are mostly used in various sensory or mental tasks (real-time EEG study). Thus, both techniques assess the functional activity of the brain. Evoked potentials provide better assessment of phenomena of psychological significance especially if the stimulus event and task are simple (Beaumont, 2008).

Structured vs. unstructured assessment procedures

Neuropsychological methods of assessment and testing can be either structured (inflexible) where all patients are subjected to a standard battery of tests. Alternatively the unstructured method (flexible) method can be used where the test design depends on the problem for referral or the patient’s symptoms (D’Amato and Hartlage, 2008). However, in this case, certain conditions must be looked for, which include what test to examine a specific function, test sensitivity, reliability, and validity, and effect of variables like age, gender, and education of the test response (Therapeutic and technology assessment subcommittee-American Academy of Neurology, 1994).

Of the structured assessment procedures Halstead- Reitan Neuropsychology Test Battery incorporates a range of tests covering the essential elements of psychological abilities. It produces information from the component of intelligence, language abilities, perceptual, psychomotor, memory, learning, and thinking abilities. It depends on using cut-off scores to separate patient’s performance because of brain damage from normal. Luria- Nebraska Neuropsychology Test whose components are motor function, rhythmic and pitch skills, tactile, visual, receptive and expressive speech functions. Components include reading and writing skills, and intellectual processes. Scoring is made through formal protocols and it has the advantages of being less time-consuming and linking to patients’ problems at a clinical level (Groth-Marnat, 2003).

In the unstructured approach, the examiner needs to be attentive to the content (what the patient says) and the process (how the patient talks or behaves during examination). In collecting patient initial data the clinician uses an unstructured or semi-structured approach where it provides flexibility and centers on the individuality of the patient. A major disadvantage of unstructured approach is examiners may be influenced by their preferred theories, personal or cultural biases (Groth-Monart, 2003). There are three inherent disadvantages of unstructured approach, which are low reliability, low validity, and lack of standardization in both content and process (US merit Systems Protection Board, 2003).

Conclusion

Irrespective of structure approach, a neuropsychiatric patient interview needs to assess patient’s strengths, adjustment level, nature and history of the disorder, diagnosis and personal and family history of relevance.

References

Beaumont, J. G. (2008). Introduction to Neuropsychology (2^nd edition). New York: The Guilford Press.

D’Amato, R. C., and Hartlage, L. C. (2008). Essentials of Neuropsychological Assessment (2^nd edition). New York: Springer.

Groth-Marnat, G. (2003). Handbook of Psychological assessment (4^th edition). New Jersey. John Wiley &Sons Inc.

Stirling, J. (2002). Introducing Neuropsychology. East Sussex. Psychology Press-Taylor Francis Group.

Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology (1994). Assessment: Neuropsychological testing of adults. Considerations for neurologists. Neurology, 47, 592-599.

U. S. Merit Systems Protection Board. (2003). The federal selection interview: Unrealized potential. Washington, DC: Office of Policy and Evaluation.

In medical psychology, metacognition has become an important area of research. In particular, the relationship between metacognition and some mental disorders is an important field. For instance, Önena, Uğurlub, and Çayköylüb (2013) attempted to determine the relationship between metacognition and insight within the context of obsessive-compulsive disorder.

Using a sample of 100 patients with compulsive mental disorder, the researchers found that metacognition scores were higher in people with obsessive disorders and good insight than in people with the disorder and poor insight.

In addition, the study indicates that metacognition is higher in people with obsessive mental disorders than in healthy people. This study indicates that there is a relationship between metacognition and insight. In this relationship, higher scores of metacognition correlate with insight.

Rogers, Jacoby and Sommers (2012) studied metacognition within the context of aging in humans. Using older adults and younger individuals, the researchers focused on false hearing and its frequency. The study found that older adults have a greater ability to benefit, but this affects their response consistently.

Hegarty, Smallman and Tull (2012), did a unique study that sought to explain metacognition based on geospatial displays. The aim was to examine the impacts of design on metacognition and performance.

Geospatial displays (weather maps) were used to determine judgment in undergraduate students and meteorologists. The findings indicate that meteorologists are slower and less accurate than students with complex than with simple weather maps.

According to Harder and Folke (2012), studies in metacognition show that ‘affect regulation’ plays an important role in social and mental interactive attention. The study reviewed recent and past research work. From the article, studies have shown that metacognition plays an important role in enhancing adaptive functioning. In this context, studies have shown that a vulnerability-stress model exists in humans.

Psychotic symptoms appear when the severity of stressors is more than a person’s vulnerability thresholds. A number of studies have also shown that the vulnerability-stress phenomenon is associated with human genomics. In fact, a study by Foster and Sahakyan (2012) has shown that vulnerability threshold is of genetic origin. However, vulnerability increases or reduces in response to stimuli.

For instance, it increases when an individual is exposed to trauma, causing the emergence of psychosis. In addition, trauma can lead to an individual’s sensitization to stress that is involved in the process of developing psychotic symptoms.

Although there is little information about the precise mechanism involved in the alteration of an individual’s response to stress in psychosis, recent evidence show that neuropsychological changes occur as a result of childhood abuse, causing psychotic symptoms.

Dansereau, Knight, and Flynn (2013), Human judgment and decision making are closely related to metacognition. These researchers have shown that poor Human judgment and decision making cause a number of problematic behaviors, especially in adolescents. Psychosis has been linked with a number of problematic behaviors in children and adolescents.

The ability of adolescents to make decisions is affected by psychosis, which indicates the need to study metacognition in order to determine how adolescents with problematic behaviors think and make decisions (Rogers, Jacoby, & Sommers, 2012).

A number of studies have also attempted to determine the link between metacognition and dementia. For instance, Thomas, Lee and Balota (2013) carried out a research to determine the role of metacognitive monitoring and dementia in adults. They investigated metamemorial monitoring in younger adults, older adults with dementia and older adults without dementia.

Young adults, older adults without dementia and those with the condition use intrinsic and extrinsic factors effectively in guiding their judgments (Foster & Sahakyan, 2012).

This study shows that metacognition may be partially impaired in dementia, but the individuals continue to use general knowledge or theory-based processing in making metamemorial monitoring predictions. According to these researchers, metamemory is the higher-order cognitive process that plays an important role in memory function.

Other studies have attempted to determine the relationship between metacognition and a number of other mental diseases or conditions. For instance, Perona-Garcel´an, Garc´ıa-Montes, Ductor-Recuerda, Vallina-Fern´andez et al., (2012) attempted to describe the relationship between metacognition, depersonalization and absorption in individuals with schizophrenia.

The study found that schizophrenic individuals with hallucinations have a high degree of depersonalization and absorption. In addition, these individuals have dysfunctional metacognitive beliefs due to their psychiatric pathology. Such studies seem to suggest that metacognition is associated with positive psychology, absorption and depersonalization (Tullis, Finley & Benjamin, 2012).

A study by Hamm, Renard, Fogley, Leonhardt and others (2012) attempted to describe metacognition in schizophrenic patients. In particular, it describes the relationship between schizophrenia and deficits in the ability to form complex representations about self and others.

In addition, investigates the stability of these deficits over time in schizophrenic individuals. Using 49 adults with schizophrenia as a study sample, the researchers have shown that metacognitive deficits are stable in schizophrenia and other related symptoms.

In addition, brain injury affects metacognition in humans. A study by Braga, Rossi, Moretto, da Silva and others (2012) indicates that acquired brain injury affects social mediation, metacognition and cooperative learning in adolescents. Such individuals show evidence of affected social relationship, which can be managed with interventions based on cooperative learning (Hegarty, Smallman & Stull, 2012).

In conclusion, studies have shown that mental diseases, brain injury and other conditions affecting the brain have an impact on metacognition (Foster, & Sahakyan, 2012). However, the precise mechanisms through which these conditions affect metacognition are not well-understood.

References

Braga, L. W., Rossi, L., Moretto, A. L., da Silva, J. M., et al. (2012). Empowering preadolescents with ABI through metacognition: Preliminary results of a randomized clinical trial. NeuroRehabilitation, 30(3), 205-212.

Dansereau, D. F., Knight, D. K., & Flynn, P. M. (2013). Improving Adolescent Judgment and Decision Making. Professional Psychology: Research and Practice, 44(4), 274–282

Foster, N. L., & Sahakyan, L. (2012). Metacognition influences item-method directed forgetting. Journal of Experimental Psychology: Learning, Memory, and Cognition, 38(5), 1309.

Hamm, J. A., Renard, S. B., Fogley, R. L., Leonhardt., et al. (2012). Metacognition and social cognition in schizophrenia: stability and relationship to concurrent and prospective symptom assessments. Journal of clinical psychology, 68(12), 1303-1312.

Harder, S., & Folke, S. (2012). Affect Regulation and Metacognition in Psychotherapy of Psychosis: An Integrative Approach. Journal of Psychotherapy Integration, 22(4), 330-343.

Hegarty, M., Smallman, H. S., & Stull, A. T. (2012). Choosing and using geospatial displays: Effects of design on performance and metacognition. Journal of Experimental Psychology Applied, 18(1), 1.

Önena, S., Uğurlub, G. K., & Çayköylüb, A. (2013). The relationship between metacognitions and insight in obsessive–compulsive disorder. Comprehensive Psychiatry 54, 541–548

Perona‐Garcelán, S., García‐Montes, J. M., Ductor‐Recuerda, M. J., Vallina‐Fernández, O., et al. (2012). Relationship of metacognition, absorption, and depersonalization in patients with auditory hallucinations. British Journal of Clinical Psychology, 51(1), 100-118.

Rogers, C. S., Jacoby, L. L., & Sommers, M. S. (2012). Frequent false hearing by older adults: The role of age differences in metacognition. Psychology and aging, 27(1), 33.

Thomas, A. K., Lee, M., & Balota, D. A. (2013). Metacognitive monitoring and dementia: How intrinsic and extrinsic cues influence judgments of learning in people with early-stage Alzheimer’s disease. Neuropsychology, 27(4), 452.

Tullis, J. G., Finley, J. R., & Benjamin, A. S. (2012). Metacognition of the testing effect: Guiding learners to predict the benefits of retrieval. Memory & cognition, 1-14.