Summary of neuroimaging
findings in selected psychiatric disorders
|Schizophrenia spectrum and
other related psychotic disorders|
Ventricular enlargement; abnormalities
in medial temporal lobe structures and superior temporal gyrus (Shenton et al. 2001; Shepherd et al. 2012).
Majority of studies report frontal lobe
abnormalities (prefrontal gray matter and orbitofrontal regions)
(Shenton et al. 2001) and anterior cingulate (Shepherd et al. 2012).
Subcortical abnormalities involving cavum
septum pellucidum, basal ganglia, corpus callosum, and thalamus (Shenton et al. 2001; Shepherd et al. 2012).
Ventricular enlargement and decreased
gray matter volumes in first-episode schizophrenic patients (Lim et al. 1996; McDonald et al. 2006).
White matter: Most DTI studies have found
fractional anisotropy reductions in various brain regions, including the
left frontal and temporal white matter (Ellison-Wright and Bullmore 2009; Kubicki et al. 2007).
PET shows relative hypometabolism in
the prefrontal cortex (Buchsbaum et al. 1982; Tamminga et al. 1992).
Metabolic abnormalities of limbic areas
(temporal lobe, anterior cingulum) (Nordahl et al. 2001; Tamminga et al. 1992).
fMRI: Meta-analysis of 41 executive-function studies in schizophrenia
revealed consistently reduced activation in the left dorsolateral
prefrontal cortex, rostral/dorsal anterior cingulate cortex, left
thalamus, and inferior/posterior cortical areas. Increased activation
was observed in several midline cortical areas (Minzenberg et al. 2009).
Magnetic resonance spectroscopy
Decreased NAA levels in frontal, temporal,
and thalamic regions (Bertolino et al. 1998; Yurgelun-Todd et al. 1996).
Antipsychotic medications associated
with selective increase in NAA in dorsolateral prefrontal cortex
(Bertolino et al. 2001).
|Mood disorders (depressive
disorders and bipolar and related disorders)|
Abnormal signal hyperintensities in frontal
cortex and basal ganglia (Videbech1997).
Bipolar: Volume increases in the globus
pallidus and putamen have also been reported (Amone et al. 2009; Kempton et al. 2008).
Ventricular enlargement and increased
sulcal prominence in patients with bipolar disorder and unipolar
depression (Elkis et al. 1995), which may be more prominent
in those with psychotic features (Strasser et al. 2005).
Volume losses in medial thalamic or hypothalamic areas that form
the walls of the third ventricle have been presumed to underlie this
enlargement. Hippocampal atrophy has also been found (Rossi et al. 2012).
Bipolar: Reductions in right prefrontal
and temporal lobe gray matter (Selvaraj et al. 2012).
Depression: Volume reductions in prefrontal
and anterior cingulate cortices and also in subcortical structures
such as caudate nucleus and putamen (Bora et al. 2012).
Depression: Hypometabolism in limbic
and dorsolateral prefrontal cortical regions, but hypermetabolism
of ventrolateral frontal cortex (Brody et al. 2001; Ketter et al. 1996).
Magnetic resonance spectroscopy
Depression: Increased choline levels
in basal ganglia and anterior cingulate (Renshaw et al. 2001; Soares et al. 1999).
|Anxiety disorders and obsessive-compulsive
and related disorders|
OCD: Unclear findings; no volume differences
in striatal or ventricular regions (Aylward et al. 1996).
Hypermetabolism in the orbitofrontal
cortex and anterior cingulum (Holzschneider and Mulert 2011; Swedo et al. 1989).
Successful treatment of OCD associated
with decreased metabolism in orbitofrontal cortex, anterior cingulum,
and caudate nucleus (Baxter et al. 1992; Swedo et al. 1992).
|Posttraumatic stress disorder|
Smaller hippocampal volumes, smaller
frontal volumes (Pitman et al. 2012).
Reduced cingulate, caudate, and insula
volumes, even in subthreshold PTSD in veterans (Herringa et al. 2012).
Altered activity in the amygdala, vmPFC,
and dACC, as well as in the hippocampus and insular cortex in individuals with
PTSD. A recent meta-analysis of 79 functional PTSD neuroimaging
studies found that the mid-ACC, dACC, and bilateral amygdala were
the most hyperactivated regions, whereas the vmPFC and inferior
frontal gyrus were the most hypoactivated regions (Pitman et al. 2012).
One PET study found a reduction
in GABA type A receptor binding throughout the cortex, hippocampus,
and thalamus in veterans with PTSD compared to veterans without
Note. ACC = anterior
cingulate cortex; dACC = dorsal anterior cingulate cortex; DTI =
diffusion tensor imaging; fMRI = functional magnetic resonance imaging;
GABA = γ‑aminobutyric acid; NAA = N-acetyl
aspartate; OCD = obsessive-compulsive disorder; PET = positron emission tomography;
PTSD = posttraumatic stress disorder; vmPFC = ventromedial prefrontal