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Executive Function Deficits among Parents of Children Diagnosed with a Disruptive Behavior Disorder

ProQuest Dissertations and Theses, 2011
Dissertation
Author: Cheryl L Loomis
Abstract:
This study examined executive functioning of parents of children diagnosed with a disruptive behavior disorder, the most common psychiatric conditions affecting children in the United States. Much is known about environmental components predisposing an individual to these disorders, yet research is lacking in the role of genetics in disruptive behavior disorders. This study examined the presence of an endophenotypical marker in the form of executive dysfunction among families affected by these disorders. The theory of endophenotypes, which states relatives of individuals with certain psychiatric conditions exhibit subclinical traits despite not exhibiting overt clinical symptoms, guided this research. To assess executive function, participants were given three neuropsychological assessments: the Color Trails Test, the Stroop Color and Word Test, and the Wisconsin Card Sorting Test. Seventy individuals between 18 and 50 participated in the study with 35 individual parents with an affected child and 35 individual parents with no affected child. Data were analyzed using one-way MANOVA to evaluate the executive functioning between the groups and multiple ANOVAs to evaluate the significance of each dependent variable. The data showed significant differences in executive function between the groups, with parents from the affected group scoring significantly lower on the tests, supporting the theory that executive dysfunction is evident among parents of affected children. The study contributes to social change by adding to what is known about the etiology of disruptive behavior disorders so clinicians can intervene at the earliest time in an effort to mitigate the maladaptive behavioral features common to these disorders as early intervention is associated with better prognosis for the child and overall healthier family dynamics.

Table of Contents LIST OF TABLES ...............................................................................................................v Chapter 1: Introduction ........................................................................................................1 Introduction to the Study ...............................................................................................1 Problem Statement .........................................................................................................2 Theoretical Constructs ...................................................................................................3 Research Question & Hypothesis ..................................................................................3 Research Question ...................................................................................................3 Hypothesis................................................................................................................3 Purpose .....................................................................................................................4 Nature of the Study ..................................................................................................4 Definition of Terms........................................................................................................4

Assumptions and Limitations ........................................................................................6 Significance of the Study ...............................................................................................6 Summary ........................................................................................................................7 Chapter 2: Literature Review ...............................................................................................8 Introduction ....................................................................................................................8 Disruptive Behavior Disorders ......................................................................................8 Overview of Disruptive Behavior Disorders ...........................................................8 Prevalence ................................................................................................................9 Symptomology .......................................................................................................10 Subtypes of Conduct Disorder ...............................................................................11 Risk Factors ...........................................................................................................12

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Executive Function System..........................................................................................14 What is Executive Function? .................................................................................14 Executive Functioning and Disruptive Behavior Disorders ..................................16 Measuring Executive Functioning .........................................................................17 Theory of Endophenotypical Markers .........................................................................18 What is an Endophenotype?...................................................................................18 Endophenotypes and Psychopathology..................................................................19 Research on Executive Function and Endophenotypes .........................................19 Summary ......................................................................................................................21 Chapter 3: Research Method ..............................................................................................23 Introduction ..................................................................................................................23 Research Design...........................................................................................................23 Study Design ..........................................................................................................23 Research Variables.................................................................................................23 Design Justification ................................................................................................24 Setting and Sample ......................................................................................................24 Sample....................................................................................................................24 Procedure and Setting ............................................................................................25 Instrumentation ............................................................................................................27 Data Collection and Analysis.......................................................................................30 Data Analysis .........................................................................................................30 Participant Protection ...................................................................................................31 Summary ......................................................................................................................31

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Chapter 4: Data Analysis ...................................................................................................33 Introduction ..................................................................................................................33 Descriptive Statistics ....................................................................................................33 Characteristics of Sample ............................................................................................33 Data Analysis ...............................................................................................................35 Results ..........................................................................................................................36 Summary ......................................................................................................................40 Chapter 5: Discussion ........................................................................................................42 Overview ......................................................................................................................42 Interpretation of Findings ............................................................................................42 Hypotheses ...................................................................................................................43 Limitations ...................................................................................................................44 Implications of Social Change .....................................................................................45 Recommendations for Future Action ...........................................................................46 Recommendations for Further Study ...........................................................................47 Concluding Statement ..................................................................................................48 References ..........................................................................................................................49 Appendix A: Consent Form ...............................................................................................63 Appendix B: Informational Pamphlet ................................................................................65 Appendix C: Example of Letter of Cooperation ................................................................66 Appendix D: Informational Pamphlet ................................................................................67 Appendix E: Initial Interview Questionnaire .....................................................................68 Appendix F: Demographics Information ...........................................................................70

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Appendix G: Providers in Area..........................................................................................73 Curriculum Vitae ...............................................................................................................74

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LIST OF TABLES Table 1: Participant Demographics ....................................................................................35 Table 2: Means and Standard Deviations for Respondent’s Age, Total Number of Affected Children, and Total Number of Children in Household .....................................37 Table 3: Shapiro-Wilk Test for Normality on Dependent Variables .................................39 Table 4: Levene’s Test of Equality of Variance ................................................................40 Table 5: Means and Standard Deviations by Participant Group ........................................42 Table 6: ANOVA by Participant Group ............................................................................42

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Chapter 1: Introduction Introduction to the Study Psychological research has often examined the use of endophenotypical markers as complimentary diagnostic indicators for various psychiatric disorders (Antila et al., 2009; Gierski, Cuervo-Lombard, Hubsch-Sonntag, Carre, & Limosin, 2009; Jester et al., 2009). The purpose of studying endophenotypical markers is to develop a better understanding of the origin, symptomology, and subsequent treatments for these disorders (Antila et al., 2009; Jester et al., 2009). Executive functioning, one category of neuropsychological function, is a form of endophenotypical marker. Executive functions are a form of behavioral self-regulation that includes, among other things, the ability to plan strategically, control oneself, adapt to changing stimuli, and learn from experience (Bryan & Luszcz, 2000). Executive functioning deficits manifest as deficient among individuals with disruptive behavior disorders (Burke, Loeber, & Birmaher, 2002) as well as various other psychiatric conditions. Executive functioning deficits have also been found among first degree relatives of individuals diagnosed with different psychiatric conditions including schizophrenia (Gur et al., 2007), bipolar disorder (Benes, 2007), attention deficit/hyperactivity disorder (Biederman et al., 2006), and autism (Losh & Piven, 2007; Wong, Maybery, Bishop, Maley, & Hallmayer, 2006). Although executive functioning deficits seem more likely among families of individuals with various psychiatric disorders, it is unknown as to whether this endophenotypical marker is present among families of disruptive behavior disordered probands. Oppositional defiant disorder, conduct disorder, and disruptive behavior not otherwise specified (NOS), the three disorders making up the category of disruptive

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behavior disorders, are the most common pediatric psychological disorders in the United States (APA, 2000). Current estimates list the incidence rate as being between 4% and 9% of the child population (APA, 2000). Comorbidity is very common among these disorders with attention deficit/hyperactivity disorder, substance use, and mood disorders being the most prevalent (APA, 2000). Considering the prevalence any new information may help clinicians understand and treat these individuals. Understanding the inherited nature of disruptive behavior disorders by studying biological parents of affected individuals may help clinicians understand, and subsequently treat more effectively, their patients. Problem Statement An initial review of the literature revealed two things. First, much research has been conducted on the environmental factors that increase the risk of being diagnosed with a disruptive behavior disorder (Burke et al., 2002; Losh & Piven, 2007). Yet less is known about the cause and origin of disruptive behavior disorders from a genetic perspective. What is the role of nature in the likelihood of developing a disruptive behavior disorder? Can an individual be genetically predisposed to these types of disorders? Although environmental factors have been implicated in disruptive behavior disorders, we know much less about the neurobiological origins. My research examined whether parents of disruptive behavior disordered probands have a deficit in executive functioning which in turn could show a biological factor influencing the prevalence of these disorders.

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Theoretical Constructs The theory driving this study is that endophenotypical markers can be used effectively to identify risk factors for psychopathology. Endophenotypes, or biological markers, are observable behaviors exhibited within a group of genetically-related individuals. The occurrence of the endophenotype is directly affected by the environment in which the group resides (Losh & Piven, 2007). Some examples of endophenotypes are: working memory problems among relatives of schizophrenia patients and impulsivity and attentional difficulties in relatives of individuals with ADHD. In addition, many studies have found positive correlations between behavioral disorders, physiology, and environmental triggers. For instance, disruptive behavior disorders have also been found to occur as a result of a combination of frontal lobe pathology and environmental triggers such as family discord and poverty (Burke et al., 2002). This multiple domain risk factor theory has been supported by empirical research for numerous other psychiatric conditions and is similar in construct to the biopsychosocial model (Engel, 1977) which defines psychopathology as a culmination, and ultimately an interaction, of an individual’s genetic composition, thoughts and emotions, and his or her environment. Research Question & Hypothesis RQ1: Is executive functioning performance impaired in parents of children diagnosed as having a disruptive behavior disorder and, if so, can someone exhibit this type of endophenotypical marker without exhibiting the clinical diagnosis? H o 1: There is no difference in executive functioning performance between parents of individuals with disruptive behavior disorders versus parents of individuals without

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disruptive behavior disorders as measured by the Stroop Color and Word test, Wisconsin Card Sorting test, and the Color Trails test. H A 1: Parents of individuals with disruptive behavior disorders have a deficit in executive functioning performance versus parents of individuals without disruptive behavior disorders as measured by the Stroop Color and Word test, Wisconsin Card Sorting test, and the Color Trails test. Purpose The purposes of this research are to (a) further explore the cause, and by association, the neuroanatomical origins, of disruptive behavior disorders by assessing parents for specific identified neuropsychological deficits; (b) add to the research that purports a multiple domain risk factor for developing a disruptive behavior disorder by looking at some biological links found among affected families; and (c) find out whether executive functioning, known to be deficient among individuals with various psychopathologies including disruptive behavior disorders, is also impaired in first degree relatives, namely the parents of these individuals. Nature of the Study This study was a quantitative, between-groups design that used a multivariate analysis of variance to evaluate the performance of adult participants across three instruments. Chapter 3 shows, in more detail, the methodological process used to explore the research question and test the study’s hypotheses. Definition of Terms Conduct Disorder: According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR, APA, 2000), conduct disorder is a disorder usually first

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diagnosed in childhood that causes significant problems in social functioning. It is similar in symptomology to oppositional defiant disorder except that conduct disorder is more severe and the violence is more aggressive, often resulting in physical and/or sexual violence toward people or animals and serious destruction of property. Disruptive Behavior Disorder: The category within the DSM-IV-TR (APA, 2000) that encompasses Conduct Disorder, Oppositional Defiant Disorder, and Disruptive Behavior NOS. Executive Functioning: A psychological system in charge of an individual’s ability to plan, adapt to changing stimuli, exhibit prosocial behavior, inhibit objectionable behavior, think in abstract terms, and control impulses. Endophenotypical Marker: A type of biological marker derived from a specific set of behavioral symptoms within a genetically linked phenotype. The main criterion for an endophenotype is that there must be a history of the trait occurring within a family (Losh & Piven, 2007). Oppositional Defiant Disorder: According to the DSM-IV-TR (APA, 2000), oppositional defiant disorder is classified as a psychiatric disorder usually first diagnosed in childhood that causes significant distress in the individual’s daily functioning. The most common symptoms include hostility, defiance, and disregard for social rules. Phenotype: Observable properties of an organism that are directly affected by the environment in which it lives and its genetic composition (Losh & Piven, 2007). Proband: An individual being studied in genetic research (Nijmeijer et al., 2009).

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Assumptions and Limitations The study assumed the following: genetics plays a significant role in the incident of disruptive behavior disorders; that the voluntary status of the participants will not bias the study; and that the instruments used in the study, the Stroop Color and Word test, Wisconsin Card Sorting test, and the Color Trails test, are reliable and valid measures for measuring the research variables. The study delimitations are as follows: All participants are adults with children diagnosed with a disruptive behavior disorder; and all instruments will be completed in one sitting. The study limitations are that the sample, due to its size and specific inclusion criteria, may not be easily generalized to the rest of the population; that the children will not be evaluated; and the sample will be selected based on disorder status (affected parent vs. unaffected parent) and therefore will not be completely random. Additionally, this study did not evaluate whether the executive functioning deficits of the participants was due to a skill deficit, meaning they lacked the capacity, or a performance deficit, meaning they lacked the motivation. Significance of the Study This study contributes to knowledge of disruptive behavior disorders in children, the most common pediatric psychiatric disorder (APA, 2000). This information will guide proper treatment; clarify the likelihood of subclinical disorders among biological relatives; and empirically test the association between biology, neuroscience, and psychology.

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Summary Disruptive behavior disorders affect a large population of children in the United States (APA, 2000). Most research on these disorders has focused on the environmental factors that are linked to the disorders; less is known about the biological origins and the association to cognitive functioning. This study examined whether one type of endophenotypical marker, a deficit in executive functioning, was present among parents with children previously diagnosed with a disruptive behavior disorder. The relationship between executive functioning performances in affected versus unaffected parents contributes to existing knowledge of the neuroanatomical origin of these disorders and its effective treatment. Chapter 2 addresses the research on executive functioning in various psychiatric populations, the origins of disruptive behavior disorders, and the multiple risk factor theory in relation to disruptive behavior disorders. Chapter 3, presents the research method employed, the target population, testing instruments, study procedures, and data analysis. Chapter 4 contains a summary of the results; chapter 5 presents a summary of the study, the conclusion, and recommendations for future research and treatment.

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Chapter 2: Literature Review Introduction The purpose of this literature review is to lay the foundation of the study by detailing past research on the topic. The chapter will begin by describing an overview of disruptive behavior disorders including the prevalence in American society, general symptomology, and associated risk factors. Next, information on executive functioning will be presented including how it is defined, how it is evaluated, and how it has been tested in past research. Last, a discussion on the theory of endophenotypes as they relate to psychopathology will be completed. Articles to substantiate the study were obtained by accessing research journals through the University’s library system via PsycARTICLES, Academic Search Premier, MedLine, and PsycInfo as well as journals and books found from outside sources and local libraries. Disruptive Behavior Disorders Overview of Disruptive Behavior Disorders As outlined in the DSM-IV-TR, the category disruptive behavior disorders consists of three individual disorders; Conduct Disorder, Oppositional Defiant Disorder, and Disruptive Disorder NOS (APA, 2000). These disorders are considered disorders most often diagnosed in childhood with typical onset happening between 6 and 14 years of age (APA, 2000). Onset is gradual and persistently escalates in severity and incidence. Disruptive behavior disorders are one of the most commonly diagnosed disorders seen among children in mental health settings (Baker & Scarth, 2002). Treatment of oppositional defiant disorder and conduct disorder is often difficult and extensive

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requiring a cooperative effort from the child, parents, extended family, and school system. Estimates of the cost of treating these disorders are projected to be approximately $10,000.00 per child annually in the United States (Foster & Jones, 2005). This figure does not account for the costs associated with the criminal justice system and public health system for these individuals. The prognosis for these children is grim, with research showing recovery rates by late adolescence occurring in fewer than 15% of patients (Lahey, Loeber, Burke, & Rathouz, 2002). Individuals with a disruptive behavior disorder are more likely than healthy counterparts to experience mood and anxiety disorders, schizophrenia, alcohol and/or drug dependence, and various somatoform disorders later during adulthood (Button et al., 2007; Copur, Turkcan, & Erdogmus, 2005; Hodgins, Tiihonen, & Ross, 2005). Copur et al. (2005) found that, among the sample of 230 male adolescents, comorbidity rates for conduct disorder and substance abuse were 46.3%. Substance abuse was also higher among male adolescents who committed multiple crimes (48.5%) versus male adolescents with no such history (14.1%). Suicide is also higher among individuals with disruptive behavior disorders compared to nonaffected peers (Houston, 2004; Spirito, 2006). Prevalence Prevalence estimates of disruptive behavior disorders are believed to be anywhere between 2% and 10% for oppositional defiant disorder and 1% and 6% for conduct disorder (Nock, Kazdin, Hiripi, & Kessler, 2007; Roberts, Roberts, & Xing, 2007). Both disorders are more common among boys than girls; however, the ratio is smaller for

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oppositional defiant disorder with more female adolescents being diagnosed now than ever before (U.S. Department of Health & Human Services, 1999). Symptomology Disruptive behavior disorders cause individuals to behave aggressively, impulsively, and with hostility (APA, 2000). Individuals often engage in risky behavior, to varying degrees, including violence, sexual promiscuity, and alcohol and substance abuse. Oppositional defiant disorder tends to manifest earlier than conduct disorder with onset occurring as early as preschool years, whereas conduct disorder is not usually diagnosed until late childhood or early adolescence (Roberts et al., 2007). Research statistics show that almost all children with conduct disorder previously had oppositional defiant disorder; however, most children with oppositional defiant disorder do not go on to develop conduct disorder (Hofvander, Ossowski, Lundstrum, Anckarsater, 2009). Overall, individuals with these disorders exhibit an inability to self-regulate, resulting in poor prosocial skills (Kramer, 2005). Deficits in executive functioning performance have been found in many studies evaluating children with disruptive behavior disorders (Dougherty et al., 2003; Fairchild et al., 2009; Hummer et al., 2010; Kronenberger et al., 2005; Taylor, 1999). Gender appears to affect the category of behavior elicited in these disorders with female adolescents tending toward more covert aggression like excluding someone from a group, lying, and manipulating and males tending toward more obvious aggressive behavior like fighting and property destruction (van Goozen & Fairchild, 2006). According to the DSM-IV-TR, in order for a diagnosis of oppositional defiant disorder to be made, the period of hostile behavior has to have lasted at least six months,

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not occur due to a mood or psychotic disorder, and cause significant disturbance in the individual’s ability to interact with others. Additionally, at least four of the following eight criteria have to be present: loses temper, argues often with authority figures, deliberately defies rules and requests, annoys others on purpose, blames others for mistakes and behaviors, is easily annoyed by others, resentful, and vindictive (APA, 2000). Common differential diagnoses include mood disorders, psychotic disorders, ADHD, and learning disorders (APA, 2000). Conduct disorder is a behavioral disorder in which there is a pervasive pattern of harmful rebellious behavior exemplified by a blatant disregard for others and society in general (Baker & Scarth, 2002). The main diagnostic difference between oppositional defiant disorder and conduct disorder is that conduct disorder is more violent resulting in criminal activity and harm to people. According to the DSM-IV-TR, the diagnostic criteria for conduct disorder includes the presence of at least three of the following: bullying, fighting, use of a weapon to hurt another, cruelty to people, cruelty to animals, robbery, forced sexual activity, fire setting, deliberate destruction of another’s property, breaking and entering, lying, stealing, staying out all night despite being told not to, running away from home, and truancy. As with oppositional defiant disorder, the symptoms must occur absent any mood or psychotic disorder. The most common differential diagnoses are oppositional defiant disorder, ADHD, mood or adjustment disorder, and, if over 18 years, antisocial personality disorder (APA, 2000). Subtypes of Conduct Disorder There are two subtypes of conduct disorder depending on the age of onset: childhood-onset type and adolescent-onset type (APA, 2000). Childhood-onset conduct

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disorder is diagnosed when symptoms begin before age 10. It occurs more often in male adolescents than female adolescents, and is associated with a poorer prognosis and more severe symptoms including hyperactivity (Hofvander et al., 2009). Individuals with this subtype are more likely to develop antisocial personality disorder as adults (Hofvander et al., 2009). Conversely, adolescent-onset conduct disorder is any conduct disorder beginning after age 10 and occurs more equally in male and female children (APA, 2000). Risk Factors Children living in families suffering serious family discord are at greater risk of developing disruptive behavior disorder (El-Sheikh & Harger, 2001; El-Sheikh, Harger, & Whitson, 2001). Physical, emotional, and sexual abuse has also been associated as a risk factor for developing disruptive behavior disorder (APA, 2000; El-Sheikh, Cummings, Kouros, Elmore-Staton, & Buckhalt, 2008; Homish, Loeber, Stouthamer- Loeber, & Wei, 2001). Research on poor mother-infant attachment has also shown a positive correlation with these disorders (Brinkmeyer, 2007). Furthermore, early institutional living, such as foster care, is also believed to be a risk factor (Pilowsky, 1995). Low socio-economic status, in particular poverty and single-parent households, has been linked to a higher incidence of disruptive behavior disorder (Tremblay et al., 2004). There is a higher than normal incidence of disruptive behavior disorders among children of alcoholic parents (Clark, Cornelius, Wood, & Vanyukov, 2004; Haber, Jacob, & Heath, 2005). Clark et al. (2004) studied 613 families with and without parental substance abuse and found a statistically significant correlation between paternal

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substance abuse and conduct disorder in offspring. Haber et al. (2005) found that genetic factors were more influential than were environment factors in the onset of offspring disruptive behavior disorders. Parental psychopathology has also been correlated with an increased chance offspring will have oppositional defiant disorder or conduct disorder (Singh et al., 2007), as has maternal depression (Gunlicks & Weissman, 2008; Hirshfeld- Becker et al., 2008; Tully, Iacono, McGue, 2008). Wakschlag, Pickett, Kasza, and Loeber (2006) evaluated 448 boys to see whether prenatal smoking was correlated with disruptive behavior disorders and found that exposed boys were more likely than their nonexposed male peers to exhibit symptoms of disruptive behavior disorders, in particular, oppositional defiant disorder. Neurochemical differences have also been shown in children with disruptive behavior disorders. Researchers tested the serotonin levels of individuals with disruptive behavior disorders and found lower levels of the neurotransmitter equated to a higher incidence of aggression (Himelstein, 2003; Malmberg, Wargelius, Lichtenstein, Oreland, & Larsson, 2008). These studies show a relationship between the presence of aggression and impulsivity and abnormal serotonin production. Abnormal cortisol production has also been associated with a higher than normal incidence of disruptive behavior disorders (Dorn et al., 2009; El-Sheikh, Erath, Buckhalt, Granger, & Mize, 2008; Hastings, Fortier, Utendale, Simard, & Robaey, 2009; van Goozen & Fairchild, 2006; van Goozen, Fairchild, Snoek, & Harold, 2007). Hastings et al. (2009) found diminished cortisol levels and hypothalamic-pituitary-adrenal (HPA) functioning among the male children in the study which tested adrenocortical functioning through saliva. Some of the HPA functioning may be affected by testosterone which is regulated not only by the testes and

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ovaries but also by the adrenal glands postpuberty. Similar studies focusing on female participants and HPA functioning has not been conducted. Neuroanatomical studies have found impairments in amygdala functioning among individuals with disruptive behavior disorders (Hariri, Mattay, Tessitore, Fera, & Weinberger, 2003; Renaud & Guile, 2004; Sterzer, Stadler, Krebs, Kleinschmidt, Poustka, 2005). The amygdala is responsible for, among other things, an individual’s autonomic reaction to fear, emotional regulation, and hormonal secretions. Additionally, the amygdala helps regulate the HPA axis which correlates to the studies above. Renaud and Guile (2004) and van Goozen et al. (2007) have argued that dysfunction of the HPA axis may be due to a combination of genetic susceptibility and chronic stress early in life. Furthermore, Kruesi, Casanova, Mannheim, and Johnson-Bilder (2004) have found a reduced prefrontal cortical volume among individuals with disruptive behavior disorders, which is the area in the brain believed to be responsible for executive functioning. Executive Function System What is Executive functioning? Executive function is commonly defined as the ability to learn from past experiences, plan, organize, formulate goals, reason, differentiate good and bad, and control impulses (Kruesi et al., 2004). The most important behavior associated with executive function may be the capacity to delay immediate gratification for the ascertainment of a better, albeit delayed, reward (Biederman et al., 2006). The case of Phineas Gage, arguably the most famous case dealing with prefrontal cortex injury, exemplifies executive dysfunction (Wagar & Thagard, 2004). Phineas Gage was a railroad worker who was impaled through the head by a railroad spike. Due

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to the injury sustained to his prefrontal cortex, his personality, and subsequently his behavior, changed dramatically (Wagar & Thagard, 2004). He was able to walk and talk but he was unable to act appropriately given a specific situation despite knowing what was considered appropriate. He essentially had no impulse control and acted in such ways as to receive instant gratification. Not surprisingly, he suffered significant personal and occupational losses. From a neuroanatomical perspective, the prefrontal cortex is the area of the brain believed to be in charge of the executive function system (Bramham et al., 2009; Kruesi et al., 2004). The prefrontal cortex is located in the very front of the brain behind the forehead. It is directly in front of the frontal lobes and relatively close to the limbic system which controls emotions and moods. An individual’s executive functioning is assessed by looking at several characteristics including the ability to make correct social judgments, apply information meaningfully, be flexible in his or her thinking, and not perseverate (Jester et al., 2009). Jester found a significant association between parental executive function performances and the participant’s child, or children’s, executive functioning performance showing hereditability. Although this study did not demonstrate causation, it did demonstrate a biological correlation. Research on the relationship between executive functioning and psychopathology has become more popular over the last decade, as evidenced by the wealth of research generated on the topic over the last thirty years. Executive functioning deficits have been found among individuals diagnosed with ADHD (Biederman et al., 2006; Bramham et al., 2009), schizophrenia (Simon, De Hert, Wampers, Peuskens, & van Winkel, 2009;

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Whitfield et al., 2009), bipolar disorder (Antila et al., 2009), alcohol and drug users (Cottencin, Nandrino, Karila, Mezerette, & Danel, 2009; Fals-Stewart & Bates, 2009), autism (Bramham et al., 2009, Schmitz et al., 2006), anorexia nervosa (Nakazato et al., 2009), fetal alcohol syndrome (Green et al., 2009) and various other psychopathologies. Executive functioning & Disruptive Behavior disorders Taylor (1999) found executive functioning deficits among 57 male children previously diagnosed with a disruptive behavior disorder between 11 and 15. One of the tests used to evaluate the executive functioning performance was the Stroop Color and Word test. Similar findings of executive dysfunction, especially impulsivity, were also found to be significantly more prevalent among individuals with conduct disorder or oppositional defiant disorder than healthy peers (Kronenberger et al., 2005). Kronenberger studied 54 adolescents between 13 and 17 to see if exposure media violence affected executive functioning. The data showed a moderate correlation between media violence exposure and aggressive behavior among the participants. The participants with a history of disruptive behavior disorder showed more significant aggression and executive dysfunction than the participants with no disruptive behavior disorders. Kronenberger found a stronger correlation among the disruptive behavior participants due to a predisposition toward executive dysfunction they exhibit. Executive function impairments, in the form of impulsivity and poor set shifting, were also identified among 42 adolescents with disruptive behavior disorders (Dougherty et al., 2003) when compared against healthy controls. A deficit was also found in left hemispheric cognitive functioning among the disruptive behavior probands but no deficit in right hemispheric functioning. This finding corresponds with earlier studies by Deckel,

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Hesselbrock, and Bauer (1996) and Teichner and Golden (2000), who found left cerebral hemispheric deficits among adults corresponded with a previous history of juvenile delinquency and childhood aggression. Furthermore, similar research on brain laterality of individuals diagnosed with antisocial personality disorder showed impaired left hemispheric functioning (Bernstein, Newman, Wallace, & Luh, 2000). Measuring Executive functioning With the increased attention given to the role of executive functioning on mental health, numerous studies have looked at how to measure executive functioning performance. Recent studies have focused on using various neuropsychological assessments and/or cognitive assessments to evaluate an individual’s performance by calculating his or her planning ability, inhibition, organizational skills, self-regulation, processing speed, and set shifting capabilities (Jester et al., 2009; Nakazato et al., 2009; Wong et al., 2006). Jester et al. (2009) used the Wisconsin Card Sorting test, the Trail Making test, and the Stop Task to measure the participants’ executive functioning performance. Nakazato et al. (2009) administered the Wisconsin Card Sorting test to the participants in their study as a way to measure set-shifting, one concept of executive functioning. Bramham et al. (2009) used three tests to measure executive functioning among their participants including the Verbal Fluency test and two subtests of the Behavioral Assessment of Dysexecutive Syndrome. Kronenberger et al. (2005) utilized the Stroop Color and Word test, Conners’ Continuous Performance test, and Wechsler’s Abbreviated Scale of Intelligence to assess the participants’ executive functioning. An overview of available research studies specifically measuring executive functioning showed the most popular tests to be those requiring an individual to

Full document contains 88 pages
Abstract: This study examined executive functioning of parents of children diagnosed with a disruptive behavior disorder, the most common psychiatric conditions affecting children in the United States. Much is known about environmental components predisposing an individual to these disorders, yet research is lacking in the role of genetics in disruptive behavior disorders. This study examined the presence of an endophenotypical marker in the form of executive dysfunction among families affected by these disorders. The theory of endophenotypes, which states relatives of individuals with certain psychiatric conditions exhibit subclinical traits despite not exhibiting overt clinical symptoms, guided this research. To assess executive function, participants were given three neuropsychological assessments: the Color Trails Test, the Stroop Color and Word Test, and the Wisconsin Card Sorting Test. Seventy individuals between 18 and 50 participated in the study with 35 individual parents with an affected child and 35 individual parents with no affected child. Data were analyzed using one-way MANOVA to evaluate the executive functioning between the groups and multiple ANOVAs to evaluate the significance of each dependent variable. The data showed significant differences in executive function between the groups, with parents from the affected group scoring significantly lower on the tests, supporting the theory that executive dysfunction is evident among parents of affected children. The study contributes to social change by adding to what is known about the etiology of disruptive behavior disorders so clinicians can intervene at the earliest time in an effort to mitigate the maladaptive behavioral features common to these disorders as early intervention is associated with better prognosis for the child and overall healthier family dynamics.