PSY341 lecture 6

What are the three executive functions (EFs), and what are their three core processes?

• Executive functions = cognitive processes supporting goal-directed behaviour

  • Working memory

  • Inhibitory control

  • Cognitive flexibility

Why are planning and organization considered complex executive abilities?

• They depend on the coordination of several executive processes rather than one isolated function

How does working memory differ from inhibitory control?

• Working memory temporarily maintains and uses information

• Inhibitory control suppresses an inappropriate/automatic response

Give an example of cognitive flexibility difficulty and identify the EF involved.

• Distress/difficulty when a routine changes may reflect impaired cognitive flexibility, or shifting between mental sets

Why can someone with ADHD focus intensely on an interesting task but struggle with routine tasks?

• ADHD can involve difficulty regulating attention, not simply a short attention span

  • Engagement and task context matter

Why can EF test performance fail to predict everyday functioning?

• Structured tests differ from everyday demands, and EF difficulties vary across individuals and situations

Why can EF deficits neither confirm nor exclude ADHD?

• EF difficulties are associated with ADHD but aren’t universal to ADHD or unique to it

  • EF tests alone cannot diagnose or rule it out

What are the five general DSM-5 ADHD diagnostic requirements?

1. Persistent inattention and/or hyperactivity

2. Onset before age 12

3. Symptoms in at least 2 settings

4. Functional interference

5. Symptoms not better explained by another mental disorder

What is the symptom-count threshold for each ADHD symptom domain in children and adolescents?

• 6+ symptoms in inattention and/or 6+ symptoms in hyperactivity/impulsivity

A child loses materials, forgets instructions, and cannot sustain attention, but doesn’t show sufficient hyperactivity-impulsivity. Which presentation fits?

• Predominantly inattentive presentation, if the inattention criteria and other diagnostic requirements are met

A child frequently interrupts, leaves their seat, and blurts out answers but does not meet the inattention threshold. Which presentation fits?

• Predominantly hyperactive-impulsive presentation, if the hyperactivity-impulsivity criteria and other diagnostic requirements are met

What distinguishes combined presentation from the two predominantly presentations?

• Both inattention and hyperactivity-impulsivity criteria are met during the past six months

Why is symptom presence in two or more settings diagnostically important?

• It helps establish that difficulties are not restricted to one context, such as a single classroom or home situation

What does ADHD in partial remission mean?

• Full criteria were previously met; for six months, fewer than the full criteria are met, but impairment persists

How do mild, moderate, and severe ADHD differ?

• Mild → minimal excess symptoms and minor impairment

• Moderate → intermediate symptoms/impairment

• Severe → many excess/particularly severe symptoms, or marked impairment

Why is functional impairment essential when assessing ADHD?

• Symptoms must interfere with or reduce the quality of social, academic, or occupational functioning

• Symptom counts alone are insufficient

What is a cognitive marker of ADHD?

• A measurable cognitive characteristic associated with ADHD

  • Not necessarily present in every person with ADHD

What patterns on the WISC-IV may occur in children with ADHD?

• Relatively weaker working memory/processing speed, or greater variability in subtest scores, compared with perceptual reasoning and verbal comprehension

What do omission and commission errors on Continuous Performance Tests indicate?

• Omission errors → associated with vigilance or missed targets

• Commission errors → associated with impulsivity/responding when one shouldn’t

Which EF domains showed the strongest and most consistent deficits in Willcutt et al. (2005)?

• Response inhibition

• Vigilance

• Working memory

• Planning

What assessment methods and instruments are used for ADHD?

• Parent and teacher rating scales (e.g. Conners 3, CBCL, BRIEF)

• WISC-IV, NESPY-II, and Continuous perfoamnce Tests

What did Mayes, Calhoun, and Crowell (2000) report about ADHD and learning disorders?

• ADHD without a learning disorder could involve learning problems

• A learning disorder without ADHD could involve attention problems

How did children with both ADHD and a learning disorder compare with children having only one?

• The comorbid group had more severe learning problems than the LD-only group and more severe attention problems than the ADHD-only group

Why must clinicians consider differential diagnoses and comorbidity during ADHD assessment?

• Attention and learning difficulties overlap across disorders

• Misattributing symptoms can lead to inaccurate diagnosis and overlooked learning needs

How heritable is ADHD and what does polygenic mean?

• Heritability is estimated at 70-80%

• Polygenic = many genetic variants contribute to susceptibility rather than one single gene determining ADHD

What familial-risk figures are there for ADHD?

• Children with ADHD are more likely to have a biological parent with ADHD (18% versus 3% in children without ADHD)

• Adults with ADHD have a reported 57% chance of having at least one child with ADHD

Which functions may be influenced by genes implicated in ADHD?

• Dopamine transport and receptors

• Cognitive functioning

• Reward and motivation

• Arousal

• Self-regulation

What brain differences did Yu et al. (2023) report in their meta-analysis?

• Gray-matter volume deductions in frontal-parietal regions, limbic system, and corpus callosum

• Hypoactivation in frontal-temporal regions, right postcentral gyrus, left insula, and corpus callosum

What developmental interpretation did the lecture draw from age-related brain findings in ADHD?

• Younger patients showed more widespread structural and functional differences than adults, suggesting greater neurodevelopmental disruption and delayed maturation.

What are the main roles of dopamine in the prefrontal cortex, striatum, and mesolimbic reward circuitry?

• Prefrontal cortex → goal control and working memory

• Striatum → action selection and reward learning

• Mesolimbic circuitry → reward prediction, motivation, and learning outcomes

What is the frontal-striatal circuit, and how is it implicated in ADHD?

• A circuit involving the prefrontal cortex and basal ganglia

• ADHD is associated with differences in this circuitry and delayed maturation, especially in prefrontal

How do Gray’s behavioural inhibition system (BIS) and behavioural activation (BAS) differ?

• BIS slows or stops behaviour in response to punishment/absent reinforcement

• BAS promotes approach and behaviour adjusted to obtain reinforcement

What is the default mode network (DMN), and what is its proposed relevance to ADHD?

• A network active by default

  • Effective task performance involves dynamic coordination between DMN and task-positive/control networks

• Impaired synchronization may contribute to difficulties

What is Barkley’s (2014) central claim about the fundamental deficit in ADHD?

• The core problem is behavioural inhibition, rather than inattention alone

Which prenatal and perinatal factors are associated with ADHD?

• Prenatal exposure to cigarettes, alcohol, or other drugs

• Premature birth, low weight, delivery complications involving hypoxia

• Sleep-related breathing problems

• Low-level lead exposure

Why should prenatal risk associations not automatically be interpreted as casual?

• These are contributing factors rather than established causal associations

• Genetic susceptibility may strengthen some associations

How do methylphenidate and amphetamine-based medications offer mechanistically?

• Methylphenidate → primarily blocks dopamine and norepinephrine transporters

• Amphetamine-based medications → affect transporter function and promote catecholamine release, among other actions

Why is it inaccurate to say stimulants simply replace missing dopamine?

• They alter catecholamine signalling in ways that can improve attention and behavioural regulation

  • Precise biological mechanisms of ADHD remain incompletely understood

Define chunking, body doubling, and reward bundling, with an example of each.

• Chunking → break homework into small steps

• Body doubling → work while another person is present

• Reward bundling → pair a task with something enjoyable (e.g. music during a chore)

Why does supportive structure often work better than nagging or punishment for ADHD-related difficulties?

• External systems reduce executive-function demands → predictable routines, visual timers, checklist, smaller steps, immediate achievable reinforcement, and co-regulation support task initiation and transitions