Letters to the Editor
Re: Using Language in Psychiatry
Dear Editor:
Fine reports that much more work remains to map the details of
language onto the details of psychiatric disorder (1). Such mapping
will eventually provide clinicians with an organized way to listen
for disorders. Recent research supports this strategy: in 2 groups
of men followed prospectively for 10 years (P < 0.05), angina
or hypertension and a sixfold coronary incidence correlated with
the rate of 1-second speech hesitation pauses (SHPs) (mean pause
duration 1.5 seconds, SD 0.33; mean pauses/minute 4.79, SD 2.48),
pauses are behavioural correlates of mood whose rats also corelated
with immobility in the face of stress and with an increase in planning
difficulty (2,3).
Neurobiological features are suggested by the correlation of rate
and variability in duration of SHPs with the left and right hemisphere,
respectively, by the association of reduced blood pressure with
longer, less recurrent pauses (about 2 seconds), and by the profound
effects on angina of consciously focusing attention on breathing
and intervening pauses. Reports that the microvascular response
to the onset of neural activity is consistently delayed by about
3 seconds and is linked to the increased coherence in electroencephalograph
gamma-band activity (30 to 50 Hz or broader, centred on 40 Hz) associated
with the execution of more complex tasks support this hypothesis.
Blood flow may increase glial processing of glutamate during sudden
increases in neuronal activation to maximize the power of intracortical
processing within the gamma-range of local field potentials (2).
This hypothesis is supported by a report that dopamine release in
the prefrontal cortex during stress is reduced by the local activation
of glutamate receptors (4), by the association of 3-second intertrial
intervals with integration of target and body-part information in
the premotor cortex when planning action (5), and by the association
of 2-to-4 second periods of rest with significant cognitive activity
(6). These findings give precise, objective methods (2) with which
to clarify the extent to which psychiatric disorders are related
to language processing problems (1).
References
1. Fine J. Using language in psychiatry.
Can J Psychiatry 2001;46:916–22.
2. Friedman EH. Re: Socioeconomic status and ischemic
stroke [letter]. Stroke 2001;32:2725.
3. Bortfeld H, Leon SD, Bloom JE, Schober MF, Brennan
SE. Disfluency rates in conversation: Effects of age, relationship,
topic, role, and gender. Lang Speech 2001;44:123–47.
4. Del Arco A, Mora F. Dopamine release in the prefrontal
cortex during stress is reduced by the local activation of glutamate
receptors. Brain Res Bull 2001;56:125–30.
5. Hoshi E, Tanji J. Integration of target and body-part
information in the premotor cortex when planning action. Nature
2000;408:466–70.
6. Stark CEL, Squire LR. When zero is not zero:
the problem of ambiguous baseline conditions in fMRI. Proc Natl
Acad Sci USA 2001;98:12760–66.
Ernest H Friedman, MD
Cleveland, Ohio
Dr Fine Replies
Dear Editor:
Dr Friedman provides data suggesting that the connection between
language data and psychiatric disorders may be through a series
of neurophysiological mechanisms (1). In particular, he proposes
that the clinical observation of pausing in language is related
to depressed mood (and perhaps to other disorders, such as pervasive
developmental disorders) and may be controlled by a complex series
of vascular and neurological events. These mechanisms must then
be related to psychiatric disorders. The functional linguistic approach
can be combined with precise neurobiological measurements to provide
a neurobiological account of both normal social functioning and
the impairments in social functioning that are considered psychiatric
disorders.
In the data presented, pauses of 2 to 3 seconds are the result
of behavioural events and the speed of neurobiological processes
(1). To advance our knowledge, these findings must be specifically
tested on the external events relevant to different psychiatric
disorders. For example, are pauses more common or longer in reaction
to stressful situations—or even, at a micro level, in reaction
to stressful utterances by another speaker? Pauses of 2 to 3 seconds
on their own do not give maximum information. The location of the
pauses in terms of language production, interaction, and hypothesized
processing factors can be studied to link psychiatric disorders
to underlying neurobiological mechanisms through language. In terms
of language production, the location of the pauses needs to be studied
at 4 stages: at the beginning of turns (when a speaker is just starting
a contribution), between clauses (when the ideas may be being formulated),
before content words (when word retrieval is in progress), and even
within words (when articulation processes are at stake). In terms
of interaction, 3 elements need to be investigated: the pauses between
speakers, each speaker’s kinds of utterance (that is, statements,
questions, commands, corrections, or follow-ups), and the relationship
between the speakers (for example, higher social position vs subordinate
social position). Finally, processing factors such as stress, information
processing, planning, executive functions, and the emotional impact
of topics will affect neurobiological processing, the use of language,
and how that language reflects psychiatric disorders. The results
will have clinical significance: they will indicate what kinds of
interactions are associated with what kinds of clinically relevant
linguistic productions and, specifically, pausing. They will also
have significance for basic science: they will indicate what the
mechanisms are behind psychiatric disorders that contribute to their
language characteristics.
A sufficiently detailed functional account of language links behaviour
in psychiatric disorders—what is socially dysfunctional—to
the underlying neurobiological mechanisms. Neurobiological mechanisms
can be related to specific characteristics of language (for example
the pausing reported by Friedman [1]), and these characteristics
of language can be related to the observed characteristics of psychiatric
disorders. Language provides a crucial intermediate step in the
analysis. It is specific enough to study neurobiologically, and
it also describes the phenomena that contribute to, if not define,
the social difficulties experienced by individuals with psychiatric
disorders (2).
References
1. Friedman E. Using language in psychiatry [letter].
Can J Psychiatry 2002;47:583.
2. Fine J. Using language in psychiatry, Can
J Psychiatry 2001;46:916–22.
Jonathan Fine
Ramat-Gan, Israel
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