Lecture 11 ADHD

Question 1

What kind of disorder is ADHD?

Answer 1

It is a cognitive neurodevelopmental disorder

Question 2

What is the criteria for ADHD

Answer 2

A persistent pattern of inattention and/or hyperactivity-impulsivity that interferes with functioning or development.

Question 3

Name the subtypes of ADHD

Answer 3

inattentive, hyperactive-impulsive or combined

Question 4

What is the prevalence of ADHD?

Answer 4

5% in children (2:1 prevalence in males)

2.5% in adults (1.6:1 in males)

Question 5

What often co-occurs with ADHD?

Answer 5

Conduct disorder, antisocial personality disorder, borderline personality disorder, bipolar disorder, depression, anxiety disorders, and substance use disorders

Question 6

What appears to cause the symptoms of ADHD?

Answer 6

Abnormal functioning of various regions of the prefrontal cortex

Question 7

Dorsal anterior cingulate cortex is important for what?

Answer 7

Selective attention

Question 8

What are the selective attention deficits in ADHD?

Answer 8

Little attention to detail
careless mistakes
does not listen
loses things
distracted
forgetful

Question 9

What does the stroop test evaluate?

Answer 9

Selective attention

Question 10

DLPFC is important for what?

Answer 10

Sustained attention

trouble following through and finishing tasks
difficulty with organization
avoids sustained mental efforts

Question 11

The premotor cortex is important for what?

Answer 11

Hyperactivity

fidgeting
gets out of seat frequently
frequent running/climbing
always on the go

Question 12

The orbitofrontal cortex is important for what?

Answer 12

Impulsivity

Talks excessively
blurts out
interrupts

Question 13

What is the low arousal theory?

Answer 13

ADHD patients suffer from low arousal of the PFC and seek activity for self stimulation

Question 14

What are possible factors for ADHD?

Answer 14

Genetics (75% of cases)

Environmental factors

Dietary factors

Childhood neglect, abuse or poor educational opportunities

Question 15

What are some of the environmental factors for ADHD?

Answer 15

alcohol, nicotine or pesticide during pregnancy results in higher risk of ADHD

Question 16

How may genetics influence ADHD?

Answer 16

Possibly related to mutations in genes encoding proteins related to monoamine transmission

Question 17

What are the dietary factors for ADHD?

Answer 17

ADHD has been associated with food colorings and preservatives

Question 18

Why does ADHD frequently occur in children?

Answer 18

May be due to abnormal neuron/synapse elimination during development of the brain.

Question 19

What is the hypothesized neural basis of ADHD?

Answer 19

Low levels of NE and DA in the PFC lead to reduced stimulation of DA and NE receptors especially alpha2A and D1 receptors.

Question 20

What is the general approach in pharmacological treatment of ADHD?

Answer 20

Increase PFC activity to more optimal levels, without “overloading” other systems to produce addiction, psychosis or motor issues.

Question 21

Name 2 NDRIs and how they work

Answer 21

Methylphenidate and dexmethylphenidate

Block DAT and NET resulting in increased stimulus of DA and NE receptors in the frontal cortex

Question 22

What composes adderall?

Answer 22

25% mixture of amphetamine aspartate, amphetamine sulfate, dextroamphetamine saccharate and dextroamphetamine sulfate

Question 23

How does adderall work?

Answer 23

Amphetamine is a substrate for VMAT and reverse DAT and NET. These amphetamines promote DA/NE release resulting in increased stimulation of DA and NE receptors in the frontal cortex

Question 24

What is lisdexamphetamine and how is it different from other amphetamines?

Answer 24

Vyvanse is dextroamphetamine conjugated to the amino acid lysine.

Vyvanse itself is inactive but acts as a prodrug to form dextroamphetamine upon cleavage of the from the molecule.

Question 25

What is beneficial about using a prodrug like vyvanse?

Answer 25

It is longer lasting and less easily abused version of dexamphetamine

Question 26

Name the 4 selective NE reuptake inhibitors (NRIs) and how they work.

Answer 26

atomextine
reboxtetine
desvenlafaxine
duloxetine

Primarily block NET, they also increase DA levels in the PFC since NETs in this region have high affinity for dopamine

Question 27

Name two selective alpha2A agonists

Answer 27

Guanfacine and clonidine

these are potentially ideal for patients whose symptoms seem to be mediated by NE deficits only.

Question 28

What is a draw back of the alpha2A agonist clonidine?

Answer 28

It is not selective and also activates alpha 2b and alpha 2c NE receptors as well as imidazoline receptors which increase side effects such as hypotension, sedation