Peter F. Goyer

Aggression in humans correlates with cerebrospinal fluid amine metabolites

Cerebrospinal fluid of the major central metabolites of serotonin (5HT), norepinephrine (NE), and dopamine (DA)--5-hydroxyindoleacetic acid (5HIAA), 3-methoxy-4-hydroxy=phenylglycol (MHPG), and homovanillic acid (HVA), respectively--were studied in a group of 26 age-similar military men with no history of major psychiatric illness, but with various personality disorders and difficulties adjusting to military life. Independently scored history of aggressive behavior showed a significant negative correlation with 5HIAA (r = -0.78) and a significant positive correlation with MHPG (r = 0.64).

Higher brain blood flow at amygdala and lower frontal cortex blood flow in PTSD patients with comorbid cocaine and alcohol abuse compared with normals.

Posttraumatic stress disorder (PTSD) patients with histories of cocaine and alcohol abuse (CA-PTSD) were compared with normal volunteers. Positron emission tomography (PET) scans with 15O-butanol were used to compare regional cerebral blood flow (rCBF) between the groups during rest and during an auditory continuous performance task (ACPT). CA-PTSD patients had significantly higher rCBF in right amygdala and left parahippocampal gyrus than normals during the ACPT. Normals had higher rCBF at frontal cortex during the resting scan and during the ACPT. The role of the amygdala in attention and fear conditioning suggests that increased amygdala rCBF may be related to clinical features of PTSD. Cocaine use may be associated with increased amygdala rCBF in PTSD patients. Amygdala and frontal cortex attention system components may be reciprocally related and their relative contributions to processing of neutral stimuli perturbed in CA-PTSD.

Attention and regional cerebral blood flow in posttraumatic stress disorder patients with substance abuse histories

Performance on an attentional task was assessed in posttraumatic stress disorder patients with substance abuse histories (PTSD-SA). Positron emission tomography (PET) was used to measure concurrent regional cerebral blood flow (rCBF). Eight male PTSD-SA patients and eight normal subjects each received three serial PET scans with 15O-labeled water under the following conditions: (1) resting, (2) auditory continuous performance task (ACPT1), and (3) repeat auditory task (ACPT2). PTSD-SA patients made more errors of commission on the ACPT than normal subjects. Examination of right frontal and parietal cortex ACPT task substrates revealed decreased parietal blood flow in PTSD-SA, which may represent a pathophysiology for poor attentional task performance in PTSD-SA. Attentional problems may underlie other symptomatology in PTSD.

Preliminary report: Brain blood flow using PET in patients with posttraumatic stress disorder and substance-abuse histories

Abstract Posttraumatic stress disorder (PTSD) is defined by DSM-III-R as an anxiety disorder characterized by recurrent distressing and intrusive remembrances of a traumatic event (American Psychiatric Association 1987). Some physiological abnormalities have been found in PTSD, notably for cardiac (Blanchard et al 1991) and neuroendocrine measures (Friedman 1991), but no studies to date have directly measured regional brain function changes in PTSD using positron emission tomography (PET). This preliminary study compares PTSD patients who have histories of substance abuse (Keane et al 1983, 1988) with normal controls who did not have a history of substance abuse. PET studies of anxiety disorders (Baxter et al 1987; Nordahl et al 1989, 1990; Reiman et al 1986), and acute (London et al 1990) and recent (Volkow et al 1991) substance abuse suggested hypotheses of increased orbital frontal cortex (OFC) blood flow and decreased left/right hippocampal ratios in PTSD patients with histories of substance abuse (PTSD-SA) compared to normal control subjects.

Assessment of the effects of ciprofloxacin and nalidixic acid on cerebral blood flow and metabolism in healthy subjects by positron emission tomography.

Study Objectives. The mechanism by which the fluorinated quinolones produce central nervous system effects is unknown. Using positron emission tomography (PET), we evaluated the effects of two quinolones on brain blood flow as well as on oxygen and glucose metabolism. These determinations were done in conjunction with ophthalmologic and neuro‐ophthalmologic testing.

Computer-aided techniques for aligning interleaved sets of nonidentical medical images

We have developed an X-window based, interactive manual technique for aligning medical images of the brain. Our methods were designed to allow easy correction of artifacts that resulted from motion during the acquisition of interleaved sets of MR images. Real-time feedback about the alignment of the data volume proved helpful to the user in obtaining a satisfactory correction. This feedback was possible by focussing on a limited number of slices at one time. Contrary to intuition, the observed motion artifact was primarily found to occur in one direction. Elimination of said artifact, however, required sub-pixel translation of images. We also did some preliminary work on automated extensions of our manual alignment technique. These automated algorithms utilized mathematical morphology for segmenting the brain and a 2-dimensional implementation of the Principal Axes technique for re-alignment of the segmented images.

Pet study correlates of psychometric psychoticism in normals

Recent positron emission tomography (PET) studies of patients with psychosis have found decreased glucose metabolism in prefrontal cortex. We examined whether psychometric psychoticism in normals was associated with reduced glucose metabolism in prefrontal cortex in 44 males (mean age 33.27 SD 10.95) and 41 females (mean age 33.04 years SD 10.87). All subjects completed the Eysenck Personality Questionnaire (EPQ), and underwent the PET scan procedure on a Scanditronix scanner during performance of an auditory continuous performance task. ume of a control region (superior frontal gyms). An analysis of the temporal sulco-gyral pattern showed a non-parallel, discontinuous pattern in schizophrenic patients (Chi Square=l0.8, df=l, p I 0.001, phi=0.60). These findings suggest that a subset of schizophrenics show localized reductions in gray matter of the temporal lobe that are intercorrelated thus suggesting a disturbance of a neural network in schizophrenia. Moreover, degree of thought disorder was related to reduced volume of left posterior STG, an area important as a substrate of language. That the gyral pattern was also disrupted strongly implicates a neurodevelopmental disturbance may be important in the aetiology of schizophrenia.