Treating Executive Dysfunction to Improve Insight in Psychiatric
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Archives of Neurology and Neuro Disorders ISSN: 2638-504X Volume 1, Issue 2, 2018, PP: 27-30 Treating Executive Dysfunction to Improve Insight in Psychiatric Disorders Prajjita Sarma Bardoloi, MBBS, FRCPC Department of Psychiatry, Queen Elizabeth II Hospital, Grande Prairie, Alberta, Canada. [email protected] *Corresponding Author: Prajjita Sarma Bardoloi, Department of Psychiatry, Queen Elizabeth II Hospital, Grande Prairie, Alberta, Canada. Abstract Executive dysfunction is not a primary psychiatric diagnosis in DSM 5, but it plays an important role in insight. This in turn determines treatment adherence, relapse prevention and functional improvement. This article shades light into importance of addressing executive dysfunction in treating acute mental illness, in order to improve overall outcome. Introduction Th ive functioning and many researchers have described Executive Function (EF) is an umbrella term that ere is no consensus definition of execut encompasses a cluster of very important cognitive overall, included similar functions. functions needed for an individual to survive in today’s these complex functions in their own definitions but critical world. The expression “Executive Function” Components of executive function became a favored title to describe those functions, because of the complexity and their roles in a person’s various researchers which include: life e.g. to guide him /her in making everyday decisions, Several components of EF have been identified by Working Memory to have goal directed activities, planning & organizing, to be able to adapt to the changes of environment, • Response Inhibition inhibit impulses and to be socially appropriate (1,4). • Set shifting Executive dysfunction is often used synonymously • Initiation frontal network syndrome. • Anticipation with frontal lobe deficits, prefrontal syndrome or The study of the functions of the brain , specially • Attention the frontal lobes, attained more attention after the • Planning & organizing famous railroad accident case of Phineas Gage in 1848, where, Mr. Gage, a young 25 year old healthy • Fluency male had a penetrating brain injury from a blast. An • Monitoring self or metacognition iron road entered through his left cheek, frontal lobe Goal directed activities and exited through his skull. He completely recovered • physically following his injuries but was left with •Working Memory serious behavioral changes. Lauria in 1966, used the Is short term memory, where an individual uses term “Frontal lobe syndrome” to describe similar cognitive function to retain information for a short symptom executive dysfunction, that was caused by period of time in order to prepare for the next step of decision making, planning and organizing. People used by Baddeley in 1986, to describe this array of functionsfrontal lobe (4). deficit. The term “Executive” was first attention, decision making, planning and organizing. with working memory problems have difficulty with Archives of Neurology and Neuro Disorders V1 . I2 . 2018 27 Treating Executive Dysfunction to Improve Insight in Psychiatric Disorders Response Inhibition Monitoring Self or Metacognition Is the ability to hold back on responding inappropriately Is the ability to monitor one’s own action or behavior, or impulsively based on previously learned responses, ability to compare and judge whether or not it is which may not be appropriate at the present scenario. appropriate to the situation or the circumstances. Goal Directed Activities becomePeople with easily difficulty distracted with and response impulsive.Patients inhibition havemay The ability to initiate and sustain one’s activities as exhibitdifficulty utilization ignoring behaviorsunnecessary (picking external up objectsstimuli withand planned and organized. Again this too needs intact no clear intent), echolalia and echopraxia. (4) other functions like working memory, attention, Set Shifting or Flexibility response inhibition, planning, organizing etc. Is the ability to change one’s action and behavior Psychiatric Disorders and Executive depending on the changes of the environment or Dysfunction Executive dysfunction is found in many psychiatric result in rigidity and perseveration. People with disorders. The neurodevelopmental disorders like circumstances. Deficit in this cognitive function would Autism, ADHD, Schizophrenia, Mood disorders, both and socialization. depression and Bipolar disorder, neurocognitive problem with flexibility find difficulty in relationships Initiation disorders, Personality disorders like borderline and antisocial personality disorders are associated with Is an important cognitive function for an individual to executive dysfunction (3). lack motivation to start a planned task. It is often found Neurobiology of Executive Function tothrive be associated in his or her with life. traumatic Persons withbrain initiation injury. deficits Executive functions are delivered like a highly Anticipation synchronized orchestra with their conductor Is the ability to predict an outcome based on previous prefrontal cortex along with areas through their experience and the circumstances. Humans have highly developed network system. The brain areas some innate abilities to predict time, place, space, responsible for EF are the prefrontal cortex, parietal comparability, causality and based on those abilities cortex, basal ganglia, thalamus and cerebellum and the they are able to anticipate a probability. This is an networks between these areas are crucial for proper important cognitive function for decision making EF. (1,5). In order for the executive functions to be and impairment of this ability would cause impaired delivered properly, the prefrontal cortex continuously decision making. monitors and controls other cortical and subcortical areas (6). The controlling of the other areas is done Attention by “Top down mechanism” by which the PFC sends is the ability to ignore the unwanted external and inhibitory signals to the subcortical areas to control internal stimuli and to covert unwanted thoughts. It is their activities. These Top down mechanism of integral to working memory functioning. functioning of PFC has been demonstrated by various Planning & Organizing studies including Trans cranial magnetic imaging studies and fMRI studies (6). By top down action PFC are the higher order cognitive functions where is able to down regulate the overactive limbic system, an individual has to have good working memory, so called emotional brain, and by this it controls an anticipation and initiation to put the gathered individual’s emotional overreaction. information into a blueprint to act on. So, we can actually call it a secondary or tertiary level of executive The executive functions develop parallel to the functioning. myelination and synapse formation in the frontal lobes. Executive functions are vulnerable to white Fluency matter injury and disturbances in cholinergic, Is the ability to maximize the production of responses noradrenergic, serotonergic and dopaminergic neurotransmitter systems in the brain (4). within28 a specific time period. Archives of Neurology and Neuro Disorders V1 . I2 . 2018 Treating Executive Dysfunction to Improve Insight in Psychiatric Disorders Dr. Arnsten and colleagues at Yale University have lesion. Amador argued that lack of insight causes been researching the role of PFC in various cognitive inability to self-monitor and self-correct leading to functions and it’s molecular biology. The dorsal and lateral PFC networks regulates the attention, thought with schizophrenia have poor insight as well as and action whereas, the ventral and medial PFC deficit in awareness (Lack of metacognition). People networks are associated with emotion regulation and regulation of the physiological state. The abstract beencognitive inconsistent. difficulties. Several studies were done to find relationship of insight and EF, but results have thinking is operated by more rostral part of the PFC. The Neurobiology of Insight PFC which is a part of the neocortex is composed of six layers of neurons, which are minutely interconnected Studies of neurobiology of insight using fMRI studies to form complex neural networks (2). Dr. Patricia Goldman-Rekic from Yale University, a pioneer of PFC lack of insight and executive dysfunction, which have found specific common areas involved in both research found that the layer III of the PFC expands are PFC, basal ganglia, parietal cortex and limbic most during primate evolution and is associated with areas (9). neuropil loss in schizophrenia. Another important Improving Executive Function to Improve discovery was that Dopamine (DA) inputs in PFC have Insight in Acutely Ill Psychiatric Patients memory which can be impaired in schizophrenia as a If we consider insight as a cognitive process and resultmodulatory of impaired effects DA on secretion dorsolateral (7). PFC and working that it shares commonalities with executive function e.g. metacognition, then hypothetically, if we Besides DA, Norepinephrine (NE) is also found to be improve executive functioning by improving the PFC equally important for PFC functioning. NE works via functioning, we will also be able to improve insight. Although it may not be as simple as it sounds. Referring to studies done by imminent researchers like Dr. postsynapticInsight ∝2A adrenoceptor stimulation (7). Goldman- Rekik and Dr. Arnsten, who emphasized Insight is a multidimensional construct which is associated with treatment adherence, global stimulation