Patterns of Cerebral Blood Flow in Schizophrenia

Abstract

Positron emission tomography was used to study the relationship between rCBF and symptom profiles in 30 schizophrenic patients. Factor analysis confirmed that the symptoms segregated into three syndromes--psychomotor poverty, disorganisation, and reality distortion--described previously. Analysis of the correlations between syndrome scores and rCBF revealed that each syndrome was associated with a specific pattern of perfusion in paralimbic and association cortex, and in related subcortical nuclei. The study confirmed predictions that psychomotor poverty and disorganisation are associated with altered perfusion at different loci in the pre-frontal cortex, and reality distortion with altered perfusion in the medial temporal lobe. The perfusion patterns suggest that the abnormalities of brain function underlying each of the three syndromes are not confined to single loci, but involve distributed neuronal networks.

5-HT Modulation of Dopamine Release in Basal Ganglia in Psilocybin-Induced Psychosis in Man—A PET Study with [11C]raclopride

“…Particularly, ego-disorders (Rüm-mele and Gnirss 1961;Vollenweider et al 1997), affective changes (Rümmele and Gnirss 1961), loosened associations (Spitzer et al 1996) and perceptual alterations commonly seen in psilocybin-induced psychosis are also observed in incipient acute schizophrenic stages (Bowers and Freedman 1966;Heimann, 1986;Gouzoulis et al 1994). In support of these suggested clinical similarities, we recently found that psilocybin produced a marked prefrontal and anterior cingulate activation in normal subjects comparable to the hyperfrontal pattern observed in some (Cleghorn et al 1989;Ebmeier et al 1993Ebmeier et al , 1995Catafau et al 1994 1994;Ebmeier et al 1995;Sabri et al 1997) but not all (Andreasen et al 1992;Buchsbaum et al 1992;Liddle et al 1992;Siegel et al 1993) acute schizophrenic patients. A number of functional animal studies have suggested that indoleamine (psilocybin, LSD) and phenylethylamine (DOI, mescaline) hallucinogens produce their psychotomimetic effects primarily through excessive stimulation of 5-HT, and 5-HT 2A receptors in particular (McKenna et al 1989;Pierce and Peroutka 1989;Aghajanian 1994;Sipes and Geyer 1994;Padich et al 1996).…”

Increased resting perfusion of the hippocampus in high positive schizotypy: A pseudocontinuous arterial spin labeling study

“…To our knowledge, this is the first application of the ASL method to investigate differences in resting perfusion in a schizotypy group. Given that the study groups only differed on the presence of schizotypal traits, and that hippocampal hyperperfusion has been reported in patients with psychosis (Friston et al, 1992; Liddle et al, 1992; Malaspina et al, 2004; Pinkham et al, 2011; Schobel et al, 2013, 2009; Talati et al, 2014, 2015; although see Andreasen et al, 1997; Catafau et al, 1994; Early et al, 1987; Parellada et al, 1994), and in people at CHR of sychosis (Allen et al, 2017, 2016; Schobel et al, 2013), our study findings suggest that increased hippocampal activity (reflected in an elevation of regional perfusion) is also involved in the expression of subclinical psychotic‐like experiences.…”

Post-Error Behavior in Active Cocaine Users: Poor Awareness of Errors in the Presence of Intact Performance Adjustments

“…Similarly, dysfunctional neural responses to errors in other clinical groups have also shown to relate to their general symptom profile. For example, patients with schizophrenia have diminished levels of ACC activity in response to errors (Kerns et al, 2005;Mathalon et al, 2002), with the level of dysfunction relating to the severity of disorganization symptoms (ie, formal thought disorder, inappropriate affect, and bizarre behavior) (Bates et al, 2002;Berman et al, 1997;Frith and Done, 1989;Liddle et al, 1992). Alzheimer's disease has also been associated with a progressive deterioration in error awareness (Cahn et al, 1997;Neils-Strunjas et al, 1998) and the neural response to errors (Mathalon et al, 2003).…”