clinical practice in brain-behavior relationships frank wood, ph.d. honorary professor of...
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Clinical Practice in Brain-Behavior Relationships
Frank Wood, Ph.D.
Honorary Professor of Behavioural MedicineNelson R. Mandela School of Medicine
Durban, Republic of South Africa
and
Professor EmeritusWake Forest University School of Medicine
Winston-Salem, NC, USA
Clinical Practice in Brain-Behavior Relationships
1. Basic dimensions in brain function.
2. Assessing the strength/weakness profile.
3. Applications to major life issues.
4. Forensic implications.
1. Basic Distinctions In Brain Function
A. Attentional Style.
B. Hemispheric Laterality .
C. Dorsal vs. Ventral Stream.
D. Episodic vs. Semantic Memory.
A. Attentional Style
Novelty:
Its detection is every brain's goal.
To seek or avoid it is every brain's choice.
The consequences of novelty are:
Arousal
Attentional Focus
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Attentional Focus
Underfocused:
Underaroused and arousal-seekingBroad. Shallow. “Big Picture.”Distractible. Flexible. Innovative.
Overfocused:
Overaroused and arousal-avoidingNarrow. Deep. Details. Perseverative. Persistent. Predictable.
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Anatomical and Clinical Perspectives on Attention
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Arousal network is medial and perceptually non-specific; it “tunes” cortical processing.
Hyperactivity and Autism.
Orbital-medial frontal vs. Dorsolateral frontal.
Stimulant medication.Alcohol, etc.
B. Laterality
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1. Neurochemical asymmetries.2. Approach, Withdrawal, & Reaction time.3. Language and Spatial Integration.
Neurochemical Laterality
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Dopamine
Target Selection and Field Independence
Reward Orientation
Approach and Avoidance
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The right hemisphere specializes in making quick decisions—the kind of decisions, usually to flee, on which survival depends.
Thus, the right hemisphere is synthetic; the left, analytic.
Language and Space
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Words are instruments of specificity. Specificity is the essence of language.
Syntax is not just coordination of content; it can be directional, i.e. “aim” thought.
The right hemisphere is not silent during language. It provides the “melody” of speech, even its accent, and—in a general sense—its context and background.
C. Dorsal and Ventral Stream
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Even within the left hemisphere, visual stimuli undergo two parallel pathways of processing:
Superior parietal-frontal, i.e.“where is it?” & “where are we going?”
Temporal, inferior parietal-frontal, i.e.“what is it?” & “what does it describe?”
D. Episodic, Semantic Memory
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Context bound event memory, for episodes of personal experience.
Context free memory, for meanings, rules, and procedures. Semantics by definition refers to things true across any episodes.
2. Assessment: History
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History is always the most important thing. Often, it's the only important thing.
For attentional style, history over-rules any cogniive tests.
Whatever the patient's condition, his/her attentional style is the first thing we must know.
Psychopathology is all about attention.
2. Assessment: History
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History is also crucial for validating:
Memory deficits. These must be understood in the context of daily life, often by report from family or colleague.
Symptoms of psychopathology.
Cross-contextual manifestations of the patient's problem.
2. Assessment: Tests
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The simpler they are, the better. It helps if they can sometimes be somewhat criterion-referenced, not only norm-referenced.
Story and Word List Recall Drawing and Figure MemoryPorteus Mazes and TrailmakingToken and Reporter Tests
2. Assessment: Neuroimaging
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Structural Neuroimaging has its limits, too: Undue lesion dependence; undocumented correlations with quantitative findings.
Functional neuroimaging, with some exceptions, is not well normed and standardized.
Neuropsychological assessment addresses different questions—developmental, competence-based, psychopathological.
3. Applications to Real Life
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Dementia & Depression: everybody faces it.Low memory can signify depression only.
Rehabilitation from Head Injury: treatment means much more than diagnosis.
Trauma, Torture, PTSD, and brain atrophy.
Academic problems: ADHD, Dyslexia, Psychosis.
m
3. Dyslexia
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N=16 DyslexiaN=15 Controls
Childhood scores documented
P<.05, corrected for multiple comparisons
Bilateral ventral temporo-occipital
Left superior temporal
4. Forensics
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By definition, forensic work requires making
an individual's neuropsychological statusrelevant to important aspects of life.
Test scores and diagnoses will be irrelevantunless they explain real life behavior
This principle is equally true for civil and
criminal cases.
Neuropsychological assessments are often
the only way to corroborate life impairment.
4. Forensics: Assembling the Narrative
Age 13 School Years Summer, 2004 Jan 2007
Selective Language Disability (7th %ile)
Left hemi-sphere
Under-achievement, Ineffective Coping
Frontal
Abusive Father
VIQ 84, PIQ 99 (13th, 47th
%iles)
Executive Dysfunction
Left & Frontal Hypo-metabolic Left & Frontal
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4. Forensics: Some Personal Conclusions
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Random, explosive violence is frontal; carefully planned violence is temporal.
Psychiatric damages are organic; e.g. PTSD; but they can often be suitably managed. Treatment is an issue that cuts both ways.
Some verbal ability is required for conciliation and peacemaking—which is a learning process, not just a negotiation.