In the State of the
art article, Elvira Bramon and RobinM.
Murray (page 243) review the results of differentinvestigations into the etiopathogenic
factors of schizo-phrenia
and suggest that a convincing model for this dis-ease
must necessarily include neurodevelopmental factorsas
well as social and environmental factors, which arethought
to act together to facilitate—if there is a geneticpredisposition—the onset of the
clinical picture.In
his Basic research article on the history of the
devel-opment of
diagnostic criteria for psychosis, Thomas A.Ban
(page 257) explains how this term has changedover the last 150 years. The concept
of psychosis wasinitially
used to cover all psychiatric disorders and cur-rently
refers to a collection of psychopathological symp-toms.
Research in neuropsychopharmacology meansthat
ever greater precision is needed for the diagnosticcriteria
of psychosis so that valid conclusions may bedrawn.
This represents a major challenge for clinical psy-chiatrists.The psychoses produced by hallucinogens
represent aninteresting
experimental model for studying the mecha-nisms
of action of these drugs and the neurobiologicalbasis
of psychoses. In the Pharmacological aspects arti-cle, Franz X. Vollenweider (page
265) reviews thebehavioral
effects and the neuroimaging findings, whichdemonstrate
that the serotoninergic hallucinogens andpsychotomimetic
anesthetics act via a common neuro-transmission
system. In contrast, the psychiatric disordersproduced
by entactogens, such as 3,4-methylene-dioxymethamphetamine (MDMA), which
can be differen-tiated
from other hallucinogens in terms of clinical andneurobiological
effects, provide a research model to enablethe
pathophysiology of psychoses to be elucidated.The
advent of second-generation neuroleptics has revo-lutionized
the pharmacological treatment of psychoses.In
an instructive Clinical research article, Carol
A. Tam-minga
and Adrienne C. Lahti (page 281) review theclinical
and pharmacological characteristics of haloperi-dol
and second-generation neuroleptics (clozapine,risperidone, olanzapine, quetiapine,
and ziprasidone),stressing
their efficacy in chronic psychoses, principallyschizophrenia,
mania, and dementia. There are current-ly
interesting developments with regard to new antipsy-chotics
in terms of other second-generation drugs, par-tial
dopaminergic agonists, “dopaminergic stabilizers,”and glutamatergic antipsychotics, which
attempt tomodify
the pathophysiology of the chronic psychosesand
promise a hopeful future for the treatment
ofpatients
with these diseases.Disorders
of attention and working memory may beevaluated
using tests of discrimination of auditory stim-uli
when tones of different frequency are presented. ThePoster prepared
by Henry Holcomb et al (page 294)uses positron emission tomography to
show cognitiveheterogeneity
in subgroups of schizophrenic patients.The
results highlight the involvement of areas such asthe
cingulum and prefrontal cortex in the brain physiol-ogy
of these cognitive dysfunctions. The
French concept of chronic psychotic hallucinations(psychose
hallucinatoire chronique [PHC]), which is cur-rently
in use, can be differentiated clinically and epi-demiologically
as well on the basis of some etiopatho-genic
elements from other psychoses of late onset. Intheir
Clinical research article, Caroline Dubertret andPhilip Gorwood (page 297) present
a clinical samplewhere
analyses of genetic epidemiology allow thehypothesis of anticipation for schizophrenia
to be putforward.
As a phenotype, PHC might help the bound-aries
of schizophrenia to be defined and offers the pos-sibility
of investigating the pattern of inheritance foranticipation
in this disease.2
4 1I n t h i s i s s u e . . .César Carvajal, MD
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