Jessica Turner, Ph.D.
Mind Research Network, Albuquerque, NM
Angela Laird, Ph.D.
University of Texas Health Sciences Center, San Antonio
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Conclusions
 Mental functions may be shorthand for complex neural
circuitry and function;
 or they may be emergent properties which cannot be
further deconstructed
 Either way we can build an ontology for them
 The link between experimental results and the mental
function they claim to be “about” needs to be clarified
 Need details of time, location, assumptions, methods.
 Need to consider the hypothetical framework; the explicit
operationalizations; the analyses done and not done; and the
caveats from the experimental context.
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I. Positive symptoms
Delusions
Hallucinations
Disorganization
II. Negative symptoms
Blunted affect
Few words (Alogia )
No initiative (Avolition )
No pleasure (Anhedonia)
Social/occupational dysfunction
Work/interpersonal relationships
Self-care
IV. Affective symptoms
Discontent/depression (Dysphoria )
Suicidality
Hopelessness
III. Cognitive symptoms
Attention
Memory
Executive functions
(eg, abstraction)
American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. Fourth ed. Text Revision. Washington DC: American
Psychiatric Association. 2000.
Slide courtesy of Dr. Jose Cañive
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The ontological status of mental function
over time
 Introspectionism
 Behaviorism
 Cognitive science
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In the extremes
Eliminative
materialism
Mental functions as
concepts will
disappear as we
understand the
brain better
Reality is epiphenomena
All we have is consciousness
and everything else is a
model
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Cognitive Paradigm
Approach
 The mental function
experimenters claim
to be studying
is not as important as
how they study it.
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Schema for cognitive experiments
 BrainMap database: Experiments have conditions
 Describe the conditions of the experiment
 Stimulus
 Instructions
 Response
 And context: Pre/post treatment? Population studied?
 And behavioral domain
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CogPO basics
Turner and Laird, 2012.
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BrainMap behavioral domains
 CogAtlas is similar
 Not complete
 Not clear which is which
 Not orthogonal
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Linking mind and behavior
 Cognitive experiments attempt to measure mental
processes
Donders, 1869.
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SZ have deficits detecting low spatial frequencies
O’Donnell et al., J. Abnormal Psychology 2002.
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Louis Wain (1860-1939)
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Sz have attention problems
Controls on average:
77% correct
Sz on average:
54% correct
Disentangling the roles of attention and perception in measuring
perceptual thresholds is not easy to do.
Carter et al., Schizophrenia Res. 2010
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Linking mind and physiology
 Cognitive neuroscience experiments attempt to measure physiological
correlates of behavior, indirectly connected to mental processes
 Attention: What is it?
 Endogenous (voluntary) attention vs Exogenous (involuntary) attention
 Posner: Experimental designs for studying voluntary attention
The differences
in speed and
accuracy among
these trials
relates to
voluntary
control of
attention
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The spatiotemporal receptive-field map of a single neuron in the unattended mode (top) and
attended mode (bottom).
McAdams C J , Reid R C J. Neurosci. 2005;25:11023-11033
©2005 by Society for Neuroscience
Cognitive neuroimaging and mental function
 Localization of function
 Effort-related increases in
signal
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Cognitive neuroimaging and mental function
Controls (L) and SZ (right) increases in BOLD signal for different attentional
task conditions.
Carter et al., Schizophrenia Res. 2010
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Linking mind and brain
 Brain Map-supported analysis of “executive function” in schizophrenia
 Also known as “cognitive control”
 41 papers with tasks including delayed match-to-sample or delayed response
(including Sternberg item recognition), go/no-go (including AX-CPT), mental
arithmetic, N-back, oddball, sequence recall, Stroop, Wisconsin Card Sort, and word
generation tasks
Minzenberg et al., Arch. Gen. Psychiatry, 2009
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Linking mind and brain
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From experiment to mental function
 Hypotheses
 Operationalization
 Analysis
 Interpretation
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Hypotheses
 We frame hypotheses within a scientific framework.
 This rules out some questions as being silly
 E.g. we don’t ask about the olfactory role of primary
visual areas
 But also keeps us from asking other questions
 Can we treat schizophrenia with cognitive training?
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Operationalization
 This is a key step in linking what we are studying in the
abstract to what we are measuring in reality
 Attention:
 Performance differences somehow capture what we mean by
attention
 Perception:
 Sensory thresholds are defined as the 50% point or 75% point
 Executive function
 How many trials do you perseverate in using a rule you’re being told
is wrong?
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Analysis
 What we do with data
is shaped by what we
think is acceptable
within our framework
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Interpretation
 The caveats are important!
 These are plausible alternative explanations for the
experiment
 Failures of operationalization



Eg. A monkey who has figured out another way to get their
juice reward or a human who is doing the study in some
completely unexpected way
The BOLD signal or other measurement is not sensitive to the
differences you want
Or it is sensitive to differences you don’t want (medication)
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Cognitive neuroimaging and
mental function
 Examples from fMRI
 It gets messy, when the linking hypotheses aren’t clear
 E.g. clinical populations: We know that the BOLD signal
doesn’t look the same, and the behavior is different; but
what does that mean about mental function per se?
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Conclusions
 Science does not work solely by building on logical
axioms.
 There is a theoretical framework behind the formation
and interpretation of every experiment.
 How we think about the experimental design and
interpretation is not context-free.
 Over time, concepts and relationships will disappear
and new ones show up
 E.g., phlogiston, DNA as a blue print, arguments over nature
vs nurture, the role of the unconscious in mental dysfunction.
 Our semantic framework for reasoning within
cognitive neuroscience has to take that into account.
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Conclusions
 How we characterize mental functions is going to
change (again!).
 The results of cognitive experiments about mental
function need to be subscripted by the experimental
methods and theoretical framework.
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