Working Definition of a Clinical Disorder: a __________ of symptoms that significantly _______ an individual’s ability to function, and is characterized by a particular symptom picture with a specifiable onset, course, _______, outcome, and response to treatment, and associated familial, psychosocial, and biological correlates.

Clinical Disorder

Onset: age of initial symptoms + how [insidious, rapid]Course: slowing worsening or improving; episodic vs chronic; waxing & waning vs continuousDuration: how long does a particular episode last?Outcome: do you fully recover?

Equifinality – multiple causes, one outcome

Multifinality – one cause, multiple outcomes

The Role of Factor Analysis inUnderstanding Clinical Disorders

WORRY

POORCONCENTRATION

NERVOUS

POOR APPETITE

IRRITABLE

TEARFULNESS

POOR ACADEMICS

INATTENTIVE

PEER RELATIONDIFFICULTIES

IMPULSIVE

HIGH ACTIVITYLEVEL

WORRY

POORCONCENTRATION

NERVOUS

IRRITABLE

TEARFULNESS

POOR ACADEMICS

INATTENTIVE

PEER RELATIONDIFFICULTIES

IMPULSIVE

HIGH ACTIVITYLEVEL

SHAREDSYMPTOMS

UNIQUESYMPTOMSthat correlatewith one another

UNIQUESYMPTOMSthat correlate with one another

Quantitative vs Qualitative Differences in child disorders [excess/deficit vs qualitative difference in presentation]

Externalizing vs Internalizing DisordersADHDConduct DisorderODD

Affective DisordersAnxiety Disorders

Conditional Probabilities as a means of understanding

Clinical Symptoms:

The Role of Sensitivity, Specificity, PPP, and NPP

Pathognomonic Symptoms

Sensitivity: what proportion of children with a particular disorder exhibit a specific symptom?

Specificity: what proportion of children without a clinical disorder do not exhibit that same symptom?

PPP: what proportion of children with a specific symptom meet full diagnostic for a specific clinical disorder?

NPP: what proportion of children without that identical symptom do not meet full diagnostic criteria for that same disorder?

Base rate

Sensitivity = A/B (true positive)Specificity = C/D (true negative)

PPP = A/ENPP = C/F

Differential Diagnosis & Conditional Probabilities

MeetsDx

Doesn’tMeet Dx

SymptomPresent

SymptomAbsent

A

C

B D

E

F

ON-TASKRESPONDER

ON-TASKNON-RESPONDER

AcademicRESPONDER

Academic NON-RESPONDER

A

PPP = A/B; GIVEN A POSITIVE RESPONSE IN ACADEMIC EFFICIENCY (B), THE PROBABILTY OF OBTAINING A POSITIVERESPONSE IN ATTENTION (A).

NPP = C/D; GIVEN NO academic improvement (D), THE PROBABILITY OF NO improvement in ATTENTION (C).

POSITIVE AND NEGATIVEPREDICTIVE POWER

C

B

D

ACTRS

.88a (.3

6) b

.93 (.22)

.98 (.11)

.90 (.28)

.80 (.45)

.97 (.2

7)

.89 (.6

0)

.97 (.17).79 (.60)

.57 (.78)

.60 (.

72)

.55 (.80)

a Positive Predictive Powerb Negative Predictive Power

AcademicPerformance

AttentionTo

Task

Self-Control

The Role of Epidemiology for Understanding Child Psychopathology

What is epidemiology?

Epidemiology is concerned with the ways in which clinical disorders and diseases occur in human populations, and with factors that influence these patterns of occurrence. Three interrelated components of epidemiological research involve:

1. Assessing the occurrence of new cases (incidence rate) or existing cases (prevalence rate) of the disorder at a given period of time or within a specific time period; [note: community vs clinic samples]

2. Assessing how the disorder is distributed in the population, which may include information concerning geographic location, gender, socioeconomic level, and race; and

3. Identifying factors associated with the variation and distribution of the disorder to enable etiological hypotheses to be generated.

The Role of Different Variables in Understanding Child Psychopathology

RELATIONSHIPAMONG VARIABLES?

CORRELATIONALRESEARCH

TEMPORALSEQUENCEUNKNOWN

IDENTIFYINGRISK FACTORS

TEMPORALSEQUENCEESTABLISHED-POSSIBLY CAUSAL

FACTORS INFLUENCINGTHE RELATIONSHIP BETWEEN VARIABLES?

MEDIATORS

IDENTIFYINGMARKERS

NON CAUSALLYRELATED

MODERATORS/PROTECTIVEFACTORS

NON-CAUSAL,BUT INFORMATIVE

HOW DOES ANTECEDENTEXERT ITS INFLUENCE?

IDENTIFYING PROCESS/MECHANISMS BY WHICHVARIABLES PRODUCEOUTCOMES/MODELS

CAN WE CONTROL ORALTER THE OUTCOME?

PREVENTION/TREATMENT

DECREASE PROBABILITYOF OCCURRENCE OR REDUCE CURRENT SYMPTOMS

WHAT EFFECT DOES IVHAVE ON DV?

EXPERIMENTALRESEARCH

ESTABLISHING CAUSALRELATIONSHIPS - MODELS

Developmental Psychopathology

• A single cause?• Direct vs. indirect effects:

A C

B

Moderator

A

B

C

Mediator

X

CB

Direct effect

Developmental Psychopathology

• A single cause?• Direct vs. indirect effects:

A C

B

Moderator

A

B

C

Mediator

X

CB

Direct effect

Moderators Treatment Symptom reduction

Maternal depressio

n

Moderator

Hinshaw (2007) – moderators of treatment response in ADHD

Mediators

From

: Journ

al o

f Irrepro

ducib

le

Resu

lts

Number of pirates

B

Global temp.

Mediator

X

45000

35000

The Relevance of Historical Influencesfor Understanding Child Psychopathology

and Treatments

Historical Influences

• Early explanations of psychopathology– Adult focused– Demonology– Somatogenesis

• Nineteenth Century– Classification-Kraeplin– Study of youth still lagged– Some childhood disorders identified

• Mental retardation received attention– Progress made on conceptualization of etiology

Historical InfluencesSigmund Freud & Psychoanalytic Theory

– Some disorders caused by psychological events– Childhood a critical time period– Structures of mind

• Id• Ego• Superego

– Levels of consciousness• Conscious • Sub or pre-conscious• Unconscious

– Psychosexual theory of development• Oral• Anal• Phallic• Latency• Genital

– Influence of Darwin (aggressive & sexual drives) [Charles Darwin 1809-1882; Sigmund Freud 1856-1939]

Historical Influences• Behaviorism and Social Learning Theory• Behavior is learned-caused by interactions with the

environment– Classical Conditioning

• Pavlov• Watson

– Law of Effect• Thorndike

– Operant Learning• Skinner

– Modeling• Bandura

Outcome of Conditioning 

Decrease BehaviorIncrease Behavior 

Response Cost(remove stimulus)

PositiveReinforcement(add stimulus)

PositiveStimulus

Punishment(add stimulus)

NegativeReinforcement(remove stimulus)

NegativeStimulus

Schematic of Operant Conditioning Relationships

Positive Reinforcement – a positively viewed stimulus followsa particular behavior and strengthens or increases the behavior.

Negative Reinforcement – a negatively viewed stimulus is removed oravoided and strengthens or increases the behavior (e.g., carrying an umbrella); 2 primary types: avoidance and escape behavior.

Punishment – a negatively viewed stimulus is presented or occurs following a behavior and weakens or reduces future occurrences of the behavior (e.g., spanking).

Response Cost – a positive stimulus is removed and strengthens orincreases a particular behavior.

Extinction – behavior is no longer followed by reinforcement anddecreases and eventually ceases in frequency.

• S-d’s – discriminative stimuli that indicate the likely occurrence of reinforcement.

• S-delta’s – stimuli that indicate the unlikely occurrence of reinforcement.

Basic Classical Conditioning Learning

No conditioningrequired

UCS: Food[unconditionedStimulus]

UCR: Salivation[unconditionedresponse becomes aconditioned response]

Neutral Stimulus: Bell [becomes a CS or conditioned stimulus after pairing

Paired temporally

Conditioningrequired