Adhd (final paper)

ADHD(Attention Deficit Hyperactivity Disorder)

Content

1.Definition and Symptoms

2.Effected parts of the nervous system

3.Functional impairments of the nervous system.

4.“Neurobiology for everyday life” helps my everyday life!

Definition and Symptoms

Definition: Attention Deficit Hyperactivity Disorder (ADHD) isthe most common childhood brain disorders and cancontinue through adolescence and adulthood. It is exemplified by the following categories of symptoms:1.Inattention

2.Hyperactivity

3.Impulsivity

DSM IV Criteria for ADHD‐


1. Inattention (6 or more of the following symptoms)a. fails to give close attention to detailsb. has difficulty sustaining attention in tasksc. does not seem to listen when spoken to directlyd. does not follow through on instructions and fails to finish e. schoolwork, etc.f. difficulty organizing tasks and activitiesg. avoids tasks that require sustained mental efforth. loses things necessary for tasks or activitiesi. easily distracted by extraneous stimulij. forgetful in daily activities


Hyperactivity and impulsivity – 6 or more of thefollowing symptoms:2. Hyperactivity

a. fidgets with hands or feet or squirms in seatb. leaves seat in classroom when

remaining seated is expectedc. runs about or climbs excessively at inappropriate timesd. difficulty playing or engaging in leisure activities quietlye. “on the go” or often acts as if “driven by a motor”f. talks excessively



3. Impulsivity g. blurts out answers before questions have been completed

h. has difficulty awaiting turn

i. interrupts or intrudes on others



Effected Parts of the Brain

Areas of the brain involved

1. Orbital prefrontal cortex (PFC)

2. Basal Ganglia

3. Cerebellum

4. Anterior Cingulate Cortex

There is 3 10% reduction in regional volumes of these brain ‐regions in people with ADHD. The greater the reduction in volume, the greater the severity of symptoms.

Rostain, AJ (2013). “Pay Attention!”, ADHD Through the Life Span, Univ. of

Pennsylvania. Coursera


1. Normal function of the Prefrontal Cortex (PFC)a. Critical for regulating behavior, attention and affect.

b. Inhibits distraction, sustains attention over a delay and divides attention.

c. PFC’s right hemisphere is important for behavioral inhibition.

d. Posterior cortical areas are essential for perception and allocating attentional resources.

Rostain, AJ (2013). “Pay Attention!”, ADHD Through the Life Span, Univ. of Pennsylvania, Coursera

2. Normal function of the Basal Ganglia a. Involved in movement b. Caudate and globus pallidus are dopamine receptor rich areas.3. Normal function of the Cerebellum a. smaller cerebellar vermis b. linked to dopamine receptor rich areas in the basal ganglia‐ and cortex.



4. Anterior Cingulate Cortex a. Key part of the executive attention system b. Has 2 divisions: cognitive and emotional c. May help keep working memory on-line during

cognitive tasks and monitors for errors d. Under activity in ADHD demonstrated in‐ numerous studies.




Functions of neurotransmitters in effected regions of the brain

1. Dopamine and dopamine circuits (fig. 1) a. attention, pleasure, reward, motivation, mood and anxiety b. Modulates cortical and basal ganglia neural circuits2. Norepinephrine and norepinephrine circuits (fig. 1) a. alertness, mood and anxiety b. Modulates dopamine circuits



Functional Impairments

Functional ImpairmentsNeurochemistry in ADHD (fig. 1)

1. Dopamine dysregulation

2. Norepinephrine dysregulation

3. Evidence froma. Actions of medications used to treat ADHD. These cause a/an

1) increase dopamine outside neuron

2) slowing re-uptake of dopamine & norepinephrine

3) increase production of dopamine & norepinephrine

b. Genes associated with ADHD regulate dopamine and norepinephrine.

c. Studies of distribution of neurotransmitters in patients with ADHD.

4. Greater the dysregulation, more severe the symptomsRostain, AJ (2013). “Pay Attention!”, ADHD Through the Life Span, Univ. of Pennsylvania. Coursera

Posterior Parietal Cortex

Pulvinar Nuc.of ThalamusAnterior

Cingulate Cortex

Prefrontal Cortex

Ventral Tegmental Area

Locus Ceruleus

Superior Colliculus

Anterior Attention System

Posterior Attention System

Dopamine neurons

Norepinephrine neurons


Figure 1:Neurochemistry in ADHD

The effects of medications on regions of thebrain effected by ADHD (fig. 1)1. Anterior attention system: prefrontal cortex, anterior cingulate cortex and the ventral tegmental area a. Enhances the effect of dopamine on effected regions of

the brain. b. Improves attention by 1) Improving ability to focus 2) Enhances on-task behavior 3) Enhances on-task cognitionRostain, AJ (2013). “Pay Attention!”, ADHD Through the Life Span, Univ. of



2. Posterior attention system: posterior parietal cortex,superior colliculus, pulvinar nucleus of the thalamus, and the locus ceruleus a. Enhances the effect of norepinephrine in these areas

b. Dampens “noise” or distractions c. Improves executive functions d. Increases the ability to inhibit inappropriate behavior

Rostain, AJ (2013). “Pay Attention!”, ADHD Through the Life Span, Univ. of Pennsylvania. Coursera


“Neurobiology for everyday life”

I have grown intellectually in this course inseveral ways. I hope it is offered again.1.Understanding the effects of stroke

a. Before: 1) symptoms of a stroke were simply right or left hemiplegia with a

contralateral facial droop.2) Areas of the brain where speech is produced and understood

(Broca’s area and Wernike’s area).3) Memory was divided simply into immediate and long term.4) Amnesia was the inability to remember the past.

a. After:1) Effects of a stroke often include

a. Effects on vision: loss right or left fields of visionb. Effects on producing speech by damage to Broca’s area c. Effects on understanding speech (receptive aphasia) by

damage to Wernike’s area.

2) Types of memory: working, implicit and explicit3) Amnesia results in the inability to make new

memories and a slow regression to recall old ones (beginning with the most recent memories progressing to the most distant).

“Neurobiology for everyday life”

Adhd (final paper)

Health & Medicine

Transcript of Adhd (final paper)