ADHD and the Development of Executive Function - by Bobby Towers
Abstract:
A thorough investigation of attention deficit hyperactivity disorder was conducted to illuminate a personal history of experiencing its characteristic symptoms, and a strong desire to understand the nature of the disorder and its cultural/evolutionary significance.
Hypothesis:
Initial intent was to gather academic support for an intuitive sense of skepticism regarding the legitimacy of the psychological phenomenon being considered a “disorder” in the first place, preferring instead to consider the symptoms to be a consequence of our inability as a species to adapt to such a rapidly changing world. The unprecedented rate of technological development has presented us with a host of bewildering distractions that no society could ever be expected to integrate without accepting serious challenges due to our thoroughly specialized biological processing schemas. We have created a culture of over-stimulation, and our natural response to it has generally been to become numb, scattered, and short-sighted. Attention deficit? I don't buy it. With all this insanity we have to deal with, being constantly bombarded with competing stimuli from every direction, our attention has become our most limited resource. It's no disorder... it's simply part of the human condition.
Conclusion:
The contents to follow will, if nothing else, demonstrate that it's not so simple.
ADHD and the Development of Executive Function
By Bobby Towers
“That kid just doesn't ever pay attention. I wonder what is wrong with him…” . . . “Honey, better make an appointment to see his doctor, it must be some kind of chemical imbalance” . . . “Shouldn't he be concerned about his grades? His chores? Respecting his elders, his teachers?” . . .
We’re living in a society of diagnoses. An individual's unique qualities are perceived as shortcomings rather than recognized for what they could very well be - aspects of creative potential. In this investigation, I would like to propose that the very characteristics that cause one to be easily distracted, are the same traits that facilitate creative insight. So I have an idea - instead of making ourselves perplexed by asking, why when we attempt to shove things down a child's throat we are not always received with rainbows of pleasure and gratitude - I suggest we ask a very different, more fundamental question: What does it actually mean to pay attention?
I do not mean paying attention as in, “Sit down and shut up!”, but… attention. The heart of this entire present inquiry rests upon the stunning realization of its full implication. The things we choose to pay attention to - we choose for a very special reason. A reason that cuts to the core of our personality. A reason that we are defined by, shaped by our true sense of identity. The things that we give our attention - we give them the essence of our vitality. We allow them to enter our being… to penetrate us… and become us. Attention… it is all that we are.
The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), published by the American Psychiatric Association, takes a decidedly different approach to this particular set of symptoms that have been collectively labeled a disorder. Specifically, it is categorized as: “A neurodevelopmental disorder, which impairs the growth and development of the brain or central nervous system”. 1 This potentially affects the development of emotion, learning, self control, and memory throughout a person's early childhood through adulthood. Some examples of other neurodevelopmental disorders are intellectual disability (previously/less politely known as mental retardation), autism and autism spectrum disorders (e.g. Aspergers), Down syndrome, and schizophrenia. 1
A combination of genetic and environmental contributing factors may be present including prenatal or infantile exposure to tobacco, alcohol, drugs or environmental toxins, premature birth, low birth weight, and of course, genetics - according to twin studies, about 75% of cases come from cognitive traits inherited from one of the parents. 2
What are these cognitive traits? A 2005 meta-analysis confirmed that ADHD positively correlates with impaired executive function - most strongly and consistently with the faculties of response inhibition, working memory, vigilance, and planning. 3 This has become the dominant view of the scientific medical community.
The first two cognitive abilities in question - response inhibition (or inhibitory control) and working memory, are among the first mental systems to appear in an infant's developing brain, typically between 7 to 12 months. Then from age 3 to 5 they undergo a spurt of rapid development, along with the first stages of cognitive flexibility, goal-directed behavior, and capability of planning. During pre-adolescence there is a marked increase in verbal working memory, goal-directed behavior, response inhibition, selective attention, strategic planning and organizational skills. 4
Any attempt to link ADHD to a specific physiological site is obviously futile, with all these cognitive functions developing independently at their own rate, and are progressively integrated together to form the complex network of brain systems responsible for our ability to concentrate.
When the development of some combination of these systems is compromised in an individual, effects manifest that characterize ADHD. They primarily include inattention and hyperactivity/impulsivity. In addition, resulting secondary effects may also have an impact on friends, family and colleagues due to disruptive behavior, academic issues, and relationship problems. Primarily inattentive patients may be easily distracted, forget details, or switch excessively between tasks - unable to complete an activity without quickly getting bored. They may lose things, fail to listen, daydream, get confused, be physically or mentally sluggish or unable to follow directions. Those suffering from hyperactive/impulsive symptoms may experience fidgeting, squirming, restlessness, impatience, make inappropriate comments, uncontrolled emotion, and frequent interruptions. 5
To understand how these effects manifest from poorly developed executive function, it is vital that we explore the nature of concentration in all of its intricacy. In order to selectively focus on a particular stimulus, other information from the senses must be filtered out and ignored. Working memory is of limited capacity, and allocating it accordingly is part of our executive function, the supervising attentional system.
Our dominant learned behavioral response to a stimulus, or “prepotent response”, was developed primarily to serve only our immediate survival needs. It must be overridden in order to achieve a more adaptive, delayed goal. We have just barely begun to learn, and the crucial skill that must be learned next is how to identify the signal from the noise to be filtered out. Paying attention is hard work - we are engaged in a battle with our own nature, by its very definition.
According to the prevailing executive function theory that our study supports, this filtering process called inhibitory response is the first solid mental process connected to concentration. 6 Working memory is the second cognitive development confirmed in the meta-analysis. It is a short-term, limited-capacity cognitive buffer that stores information and permits its manipulation to guide decision-making and behavior. This is the place where the active, conscious agent of our awareness lives - the "I" with which we identify - it is here that the impression of our experience that constitute our sense of self is accessed and processed. As the sensory information is captured through the "bottom-up" process of perceptual awareness, the prefrontal cortex exerts “top-down” cognitive control, receiving its input from other cortical regions such as the association cortex, thalamus, and subcortical structures subserving emotion and motivation such as the amygdala and central striatum, or nucleus accumbens. 6
The negative effects of ADHD present conditions in which prepotent responses dominate behavior. ADHD as we are conceptualizing it here is a disorder of executive faculty, a reduced ability to exert and maintain cognitive control of behavior. It is a diminished ability to inhibit responses to irrelevant stimuli (impaired interference suppression).
The third aspect of executive function is planning (forethought) - thinking about and organizing the activities required to achieve a desired goal. An anticipatory decision-making process to deal with the complexities of evaluating each set of interrelated decisions. It is a selection of missions and objectives for translating knowledge into action. 6
Finally, vigilance is sustained concentration, the ability to maintain focus over prolonged periods of time. The deterioration in the ability to remain vigilant for critical signals with time, as indicated by a decline in the rate of the correct detection of signals is known as the vigilance decrement. This decrease in attention becomes significant within the first 15 minutes under most conditions, and even faster if there exists a high cognitive demand. 7
According to signal detection theory, we are engaged in a decision making process in which we continually vary our sensitivity to sensory input to allow more or less correct detections at the respective cost of false alarms. This is known as criterion shift. The strategy creates a bias, based on how many false alarms we are willing to tolerate to achieve a higher rate of detection, thereby minimizing the consequences of either missed targets or false positives.
Vigilance is dependant on the state of arousal, taking place in the amygdala, which plays an important role in the recognition of emotional stimuli. 8
Research conducted in the 1940s demonstrated that psychostimulant medications, when given to participants, caused a highly significant reduction of the vigilance decrement. This is the targeted effect of modern pharmaceutical treatment for ADHD. 9
Medications however, only address the symptoms in the short-term. The best methods for long-term management of ADHD involve encouraging healthy learning skills though behavioral therapy. Aerobic exercise is proven to have a positive strengthening effect on the cognitive processes needing development. 10
The results of our research have been very enlightening. Our original hypothesis, that ADHD is not actually a disorder, may be trivially plausible, as there is a long history of controversy regarding the diagnosis. There are certainly cases where it is misidentified due to other factors. However, quite early on in the course of study this stance was showing to be off-base, due to the very specified diagnostic criteria. After all, it is not by low intelligence or an act of rebellion that these indications manifest. The individual presenting actual ADHD possesses both the desire and the intellect to perform tasks, but is specifically and excessively lacking in the areas of executive function compared to individuals of similar age.
Clinical psychology is often perceived as arbitrarily judgemental. But when properly understood through the scope of its own definitional landscape, this misconception is quickly put to rest.
References
1. “Attention Deficit Hyperactivity Disorder". National Institute of Mental Health. Retrieved 5 March 2016.
2. [64] Neale, BM; Medland, SE; Ripke, S; et al. (September 2010).
"Meta-analysis of genome-wide association studies of attention-deficit/hyperactivity disorder". J Am Acad Child Adolesc Psychiatry 49 (9): 884–897. doi:10.1016/j.jaac.2010.06.008. PMC 2928252. PMID 20732625.
3. Biological Psychiatry. 2005 Jun 1;57(11):1336-46. Validity of the executive function theory of attention-deficit/hyperactivity disorder: a meta-analytic review.
Willcutt EG1, Doyle AE, Nigg JT, Faraone SV, Pennington BF. http://www.ncbi.nlm.nih.gov/pubmed/15950006
4. De Luca, Cinzia R.; Leventer, Richard J. (2008). "Developmental trajectories of executive functions across the lifespan". In Anderson, Peter; Anderson, Vicki; Jacobs, Rani. Executive functions and the frontal lobes: a lifespan perspective. Washington, DC: Taylor & Francis. pp. 3–21. ISBN 1-84169-490-8. OCLC 182857040.
5. American Psychiatric Association (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington: American Psychiatric Publishing. pp. 59–65. ISBN 0890425558.
By Bobby Towers
“That kid just doesn't ever pay attention. I wonder what is wrong with him…” . . . “Honey, better make an appointment to see his doctor, it must be some kind of chemical imbalance” . . . “Shouldn't he be concerned about his grades? His chores? Respecting his elders, his teachers?” . . .
We’re living in a society of diagnoses. An individual's unique qualities are perceived as shortcomings rather than recognized for what they could very well be - aspects of creative potential. In this investigation, I would like to propose that the very characteristics that cause one to be easily distracted, are the same traits that facilitate creative insight. So I have an idea - instead of making ourselves perplexed by asking, why when we attempt to shove things down a child's throat we are not always received with rainbows of pleasure and gratitude - I suggest we ask a very different, more fundamental question: What does it actually mean to pay attention?
I do not mean paying attention as in, “Sit down and shut up!”, but… attention. The heart of this entire present inquiry rests upon the stunning realization of its full implication. The things we choose to pay attention to - we choose for a very special reason. A reason that cuts to the core of our personality. A reason that we are defined by, shaped by our true sense of identity. The things that we give our attention - we give them the essence of our vitality. We allow them to enter our being… to penetrate us… and become us. Attention… it is all that we are.
The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), published by the American Psychiatric Association, takes a decidedly different approach to this particular set of symptoms that have been collectively labeled a disorder. Specifically, it is categorized as: “A neurodevelopmental disorder, which impairs the growth and development of the brain or central nervous system”. 1 This potentially affects the development of emotion, learning, self control, and memory throughout a person's early childhood through adulthood. Some examples of other neurodevelopmental disorders are intellectual disability (previously/less politely known as mental retardation), autism and autism spectrum disorders (e.g. Aspergers), Down syndrome, and schizophrenia. 1
A combination of genetic and environmental contributing factors may be present including prenatal or infantile exposure to tobacco, alcohol, drugs or environmental toxins, premature birth, low birth weight, and of course, genetics - according to twin studies, about 75% of cases come from cognitive traits inherited from one of the parents. 2
What are these cognitive traits? A 2005 meta-analysis confirmed that ADHD positively correlates with impaired executive function - most strongly and consistently with the faculties of response inhibition, working memory, vigilance, and planning. 3 This has become the dominant view of the scientific medical community.
The first two cognitive abilities in question - response inhibition (or inhibitory control) and working memory, are among the first mental systems to appear in an infant's developing brain, typically between 7 to 12 months. Then from age 3 to 5 they undergo a spurt of rapid development, along with the first stages of cognitive flexibility, goal-directed behavior, and capability of planning. During pre-adolescence there is a marked increase in verbal working memory, goal-directed behavior, response inhibition, selective attention, strategic planning and organizational skills. 4
Any attempt to link ADHD to a specific physiological site is obviously futile, with all these cognitive functions developing independently at their own rate, and are progressively integrated together to form the complex network of brain systems responsible for our ability to concentrate.
When the development of some combination of these systems is compromised in an individual, effects manifest that characterize ADHD. They primarily include inattention and hyperactivity/impulsivity. In addition, resulting secondary effects may also have an impact on friends, family and colleagues due to disruptive behavior, academic issues, and relationship problems. Primarily inattentive patients may be easily distracted, forget details, or switch excessively between tasks - unable to complete an activity without quickly getting bored. They may lose things, fail to listen, daydream, get confused, be physically or mentally sluggish or unable to follow directions. Those suffering from hyperactive/impulsive symptoms may experience fidgeting, squirming, restlessness, impatience, make inappropriate comments, uncontrolled emotion, and frequent interruptions. 5
To understand how these effects manifest from poorly developed executive function, it is vital that we explore the nature of concentration in all of its intricacy. In order to selectively focus on a particular stimulus, other information from the senses must be filtered out and ignored. Working memory is of limited capacity, and allocating it accordingly is part of our executive function, the supervising attentional system.
Our dominant learned behavioral response to a stimulus, or “prepotent response”, was developed primarily to serve only our immediate survival needs. It must be overridden in order to achieve a more adaptive, delayed goal. We have just barely begun to learn, and the crucial skill that must be learned next is how to identify the signal from the noise to be filtered out. Paying attention is hard work - we are engaged in a battle with our own nature, by its very definition.
According to the prevailing executive function theory that our study supports, this filtering process called inhibitory response is the first solid mental process connected to concentration. 6 Working memory is the second cognitive development confirmed in the meta-analysis. It is a short-term, limited-capacity cognitive buffer that stores information and permits its manipulation to guide decision-making and behavior. This is the place where the active, conscious agent of our awareness lives - the "I" with which we identify - it is here that the impression of our experience that constitute our sense of self is accessed and processed. As the sensory information is captured through the "bottom-up" process of perceptual awareness, the prefrontal cortex exerts “top-down” cognitive control, receiving its input from other cortical regions such as the association cortex, thalamus, and subcortical structures subserving emotion and motivation such as the amygdala and central striatum, or nucleus accumbens. 6
The negative effects of ADHD present conditions in which prepotent responses dominate behavior. ADHD as we are conceptualizing it here is a disorder of executive faculty, a reduced ability to exert and maintain cognitive control of behavior. It is a diminished ability to inhibit responses to irrelevant stimuli (impaired interference suppression).
The third aspect of executive function is planning (forethought) - thinking about and organizing the activities required to achieve a desired goal. An anticipatory decision-making process to deal with the complexities of evaluating each set of interrelated decisions. It is a selection of missions and objectives for translating knowledge into action. 6
Finally, vigilance is sustained concentration, the ability to maintain focus over prolonged periods of time. The deterioration in the ability to remain vigilant for critical signals with time, as indicated by a decline in the rate of the correct detection of signals is known as the vigilance decrement. This decrease in attention becomes significant within the first 15 minutes under most conditions, and even faster if there exists a high cognitive demand. 7
According to signal detection theory, we are engaged in a decision making process in which we continually vary our sensitivity to sensory input to allow more or less correct detections at the respective cost of false alarms. This is known as criterion shift. The strategy creates a bias, based on how many false alarms we are willing to tolerate to achieve a higher rate of detection, thereby minimizing the consequences of either missed targets or false positives.
Vigilance is dependant on the state of arousal, taking place in the amygdala, which plays an important role in the recognition of emotional stimuli. 8
Research conducted in the 1940s demonstrated that psychostimulant medications, when given to participants, caused a highly significant reduction of the vigilance decrement. This is the targeted effect of modern pharmaceutical treatment for ADHD. 9
Medications however, only address the symptoms in the short-term. The best methods for long-term management of ADHD involve encouraging healthy learning skills though behavioral therapy. Aerobic exercise is proven to have a positive strengthening effect on the cognitive processes needing development. 10
The results of our research have been very enlightening. Our original hypothesis, that ADHD is not actually a disorder, may be trivially plausible, as there is a long history of controversy regarding the diagnosis. There are certainly cases where it is misidentified due to other factors. However, quite early on in the course of study this stance was showing to be off-base, due to the very specified diagnostic criteria. After all, it is not by low intelligence or an act of rebellion that these indications manifest. The individual presenting actual ADHD possesses both the desire and the intellect to perform tasks, but is specifically and excessively lacking in the areas of executive function compared to individuals of similar age.
Clinical psychology is often perceived as arbitrarily judgemental. But when properly understood through the scope of its own definitional landscape, this misconception is quickly put to rest.
References
1. “Attention Deficit Hyperactivity Disorder". National Institute of Mental Health. Retrieved 5 March 2016.
2. [64] Neale, BM; Medland, SE; Ripke, S; et al. (September 2010).
"Meta-analysis of genome-wide association studies of attention-deficit/hyperactivity disorder". J Am Acad Child Adolesc Psychiatry 49 (9): 884–897. doi:10.1016/j.jaac.2010.06.008. PMC 2928252. PMID 20732625.
3. Biological Psychiatry. 2005 Jun 1;57(11):1336-46. Validity of the executive function theory of attention-deficit/hyperactivity disorder: a meta-analytic review.
Willcutt EG1, Doyle AE, Nigg JT, Faraone SV, Pennington BF. http://www.ncbi.nlm.nih.gov/pubmed/15950006
4. De Luca, Cinzia R.; Leventer, Richard J. (2008). "Developmental trajectories of executive functions across the lifespan". In Anderson, Peter; Anderson, Vicki; Jacobs, Rani. Executive functions and the frontal lobes: a lifespan perspective. Washington, DC: Taylor & Francis. pp. 3–21. ISBN 1-84169-490-8. OCLC 182857040.
5. American Psychiatric Association (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington: American Psychiatric Publishing. pp. 59–65. ISBN 0890425558.
6. Malenka RC, Nestler EJ, Hyman SE (2009). "Chapter 13: Higher Cognitive Function and Behavioral Control". In Sydor A, Brown RY. Molecular Neuropharmacology: A Foundation for Clinical Neuroscience (2nd ed.). New York: McGraw-Hill Medical. pp. 313–321. ISBN 9780071481274.
7. Mackworth, N.H. (1948). The breakdown of vigilance during prolonged visual search, Quarterly Journal of Experimental Psychology, 1, 6-21.
8. Green, D.M. & Swets, J.A. (1966) Signal Detection Theory and Psychophysics. New York: Wiley
9. Mackworth, J.F. (1965) The effect of amphetamine on the detectability of signals in a vigilance task. Canadian Journal of Psychology 19 (2). 104-117
10. Fabiano GA, Pelham WE, Coles EK, Gnagy EM, Chronis-Tuscano A, O'Connor BC (March 2009). "A meta-analysis of behavioral treatments for attention-deficit/hyperactivity disorder". Clin Psychol Rev 29 (2): 129–140. doi:10.1016/ j.cpr.2008.11.001. PMID 19131150.
7. Mackworth, N.H. (1948). The breakdown of vigilance during prolonged visual search, Quarterly Journal of Experimental Psychology, 1, 6-21.
8. Green, D.M. & Swets, J.A. (1966) Signal Detection Theory and Psychophysics. New York: Wiley
9. Mackworth, J.F. (1965) The effect of amphetamine on the detectability of signals in a vigilance task. Canadian Journal of Psychology 19 (2). 104-117
10. Fabiano GA, Pelham WE, Coles EK, Gnagy EM, Chronis-Tuscano A, O'Connor BC (March 2009). "A meta-analysis of behavioral treatments for attention-deficit/hyperactivity disorder". Clin Psychol Rev 29 (2): 129–140. doi:10.1016/ j.cpr.2008.11.001. PMID 19131150.
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