Biomedical subjects

Roger K Pitman

Publications and source records attributed to Roger K Pitman.

At least 37 records · Page 2Linked to original sources

PubMed2004

Cavum septum pellucidum in monozygotic twins discordant for combat exposure: relationship to posttraumatic stress disorder.

BACKGROUND: Abnormally large cavum septum pellucidum has been reported in posttraumatic stress disorder; however, the origin of this association is uncertain. METHODS: We utilized magnetic resonance imaging to measure cavum septum pellucidum in pairs of identical twins discordant for combat exposure in Vietnam. RESULTS: Presence of abnormal cavum septum pellucidum was significantly correlated between exposed and unexposed twins, indicating that it is partially determined by heredity and/or shared environment. There was a greater proportion of cavum septum pellucidum in combat-exposed twins with posttraumatic stress disorder and their noncombat-exposed co-twins. CONCLUSIONS: The presence of abnormally large cavum septum pellucidum is a familial vulnerability factor for posttraumatic stress disorder.

Chi-Square Distribution↗

PubMed2004

Regional cerebral blood flow in the amygdala and medial prefrontal cortex during traumatic imagery in male and female Vietnam veterans with PTSD.

CONTEXT: Theoretical neuroanatomic models of posttraumatic stress disorder (PTSD) and the results of previous neuroimaging studies of PTSD highlight the potential importance of the amygdala and medial prefrontal regions in this disorder. However, the functional relationship between these brain regions in PTSD has not been directly examined. OBJECTIVE: To examine the relationship between the amygdala and medial prefrontal regions during symptom provocation in male combat veterans (MCVs) and female nurse veterans (FNVs) with PTSD. DESIGN: Case-control study. SETTING: Academic medical center. PARTICIPANTS: Volunteer sample of 17 (7 men and 10 women) Vietnam veterans with PTSD (PTSD group) and 19 (9 men and 10 women) Vietnam veterans without PTSD (control group). MAIN OUTCOME MEASURES: We used positron emission tomography and the script-driven imagery paradigm to study regional cerebral blood flow (rCBF) during the recollection of personal traumatic and neutral events. Psychophysiologic and emotional self-report data also were obtained to confirm the intended effects of script-driven imagery. RESULTS: The PTSD group exhibited rCBF decreases in medial frontal gyrus in the traumatic vs neutral comparison. When this comparison was conducted separately by subgroup, MCVs and FNVs with PTSD exhibited these medial frontal gyrus decreases. Only MCVs exhibited rCBF increases in the left amygdala. However, for both subgroups with PTSD, rCBF changes in medial frontal gyrus were inversely correlated with rCBF changes in the left amygdala and the right amygdala/periamygdaloid cortex. Furthermore, in the traumatic condition, for both subgroups with PTSD, symptom severity was positively related to rCBF in the right amygdala and negatively related to rCBF in medial frontal gyrus. CONCLUSIONS: These results suggest a reciprocal relationship between medial prefrontal cortex and amygdala function in PTSD and opposing associations between activity in these regions and symptom severity consistent with current functional neuroanatomic models of this disorder.

Amygdala↗

PubMed2004

Risk factors and outcome in ambulatory assault victims presenting to the acute emergency department setting: implications for secondary prevention studies in PTSD.

Prevention of post-traumatic stress disorder (PTSD) in trauma victims is an important public health goal. Planning for the studies required to validate prevention strategies requires identification of subjects at high risk and recruitment of unbiased samples that represent the larger high-risk population (difficult because of the avoidance of many trauma victims). This study recruited high-risk victims of interpersonal violence (sexual or physical assault) presenting to an urban emergency department for prospective 1- and 3-month follow-up. Of 546 victims who were approached about participating, only 56 agreed to be contacted and only 46 participated in either the 1- or 3-month interviews. Of the 46, 43 had been previously victimized with a mean of over six traumas in the group; 21% had prior PTSD, 85% had prior psychiatric illness, and 37% had prior substance abuse. Sixty-seven percent had positive urine for alcohol or drugs on presentation. Fifty-six percent developed PTSD at 1 or 3 months with the rate declining between 1 and 3 months. There was high use of medical and psychiatric services. These findings document both the difficulty of recruiting large samples of high-risk assault victims to participate in research, and the high rate of prior traumatization, PTSD, substance use, and psychiatric morbidity in these subjects which, if still active at the time of victimization, may complicate efforts to document preventive treatment effects.

Adolescent↗

PubMed2004

Hippocampal function in posttraumatic stress disorder.

Recent studies have reported memory deficits and reduced hippocampal volumes in posttraumatic stress disorder (PTSD). The goal of the current research was to use functional neuroimaging and a validated explicit memory paradigm to examine hippocampal function in PTSD. We used positron emission tomography (PET) and a word-stem completion task to study regional cerebral blood flow (rCBF) in the hippocampus in 16 firefighters: 8 with PTSD (PTSD group) and 8 without PTSD (Control group). During PET scanning, participants viewed three-letter word stems on a computer screen and completed each stem with a word they had previously encoded either deeply (High Recall condition) or shallowly (Low Recall condition). Relative to the Control group, the PTSD group exhibited significantly smaller rCBF increases in the left hippocampus in the High vs Low Recall comparison. However, this finding reflected relatively elevated rCBF in the Low Recall condition in the PTSD group. Collapsing across High and Low Recall conditions, (1) the PTSD group had higher rCBF in bilateral hippocampus and left amygdala than the Control group, and (2) within the PTSD group, symptom severity was positively associated with rCBF in hippocampus and parahippocampal gyrus. The groups did not significantly differ with regard to accuracy scores on the word-stem completion task. The PTSD group had significantly smaller right (and a trend for smaller left) hippocampal volumes than the Control group. The results suggest an abnormal rCBF response in the hippocampus during explicit recollection of nonemotional material in firefighters with PTSD, and that this abnormal response appears to be driven by relatively elevated hippocampal rCBF in the comparison condition.

Adult↗

PubMed2004

Persistence and change of PTSD symptomatology--a longitudinal co-twin control analysis of the Vietnam Era Twin Registry.

INTRODUCTION: Previous twin studies have demonstrated a strong association between the degree of combat exposure and PTSD, and the continued presence of PTSD, almost two decades after combat. Independent genetic effects have also been demonstrated for both combat exposure and PTSD vulnerability in Vietnam veterans. The current study, involving a subset of male-male twin pairs discordant for service in Southeast Asia (SEA), is a follow-up to an earlier study conducted in 1987. The purpose of this study is to examine the changes in the combat exposure-PTSD relationship over an additional decade of time. METHODS: The Mississippi Scale for Combat-Related or Civilian PTSD was administered by telephone in 1997 during a follow-up survey of the Vietnam Era Twin Registry. Only twins discordant for service in Southeast Asia who originally participated in the 1987 study were included. Results of this scale and the original 1987 PTSD symptom scale were separately standardized using z-score transformations and used as dependent variables in a random effects regression model with zygosity, time and combat exposure as independent variables. Main effects and interactions were estimated to address whether there were differential effects of combat on PTSD over time, and whether there was evidence of genetic covariation between combat exposure and PTSD in 1987 that persisted to 1997. RESULTS: Combat exposure was strongly associated with PTSD in both 1987 and 1997. Although still highly significant, the effect sharply diminished over time. There is little evidence for a shared genetic vulnerability between combat and PTSD in either 1987 or 1997. CONCLUSION: This analysis documents the continuing role of combat exposure (i. e., trauma severity) on the persistence and chronicity of PTSD. Nearly 25 years after the end of hostilities, PTSD symptoms continue to be elevated in those exposed to the highest levels of combat. There is no evidence that genetic influences on exposure to combat are shared with those inducing a genetic vulnerability to PTSD. Clinicians need to be aware of the persistent and long-term residual effects of trauma exposure.

Humans↗

PubMed2004

PTSD arousal and depression symptoms associated with increased right-sided parietal EEG asymmetry.

Researchers have proposed that depression and particular types of anxiety are associated with unique patterns of regional brain activation. The authors examined the relationship among posttraumatic stress disorder (PTSD), anxiety, and depressive symptoms and frontal, temporal, and parietal EEG alpha asymmetry in female Vietnam War nurse veterans. The results indicate that PTSD arousal symptoms are associated with increased right-sided parietal activation. However, the combination of arousal, depression, and their interaction explain more than twice the variance in parietal asymmetry compared with arousal alone. The results support the contention that the association between anxiety and right-sided posterior activation is specific to the anxious arousal subtype. These findings underscore the importance of isolating, both theoretically and statistically, emotional subcomponents in studies of regional brain activation.

Arousal↗

PubMed2004

Psychophysiological responding during script-driven imagery in people reporting abduction by space aliens.

Is recollection of highly improbable traumatic experiences accompanied by psychophysiological responses indicative of intense emotion? To investigate this issue, we measured heart rate, skin conductance, and left lateral frontalis electromyographic responses in individuals who reported having been abducted by space aliens. Recordings of these participants were made during script-driven imagery of their reported alien encounters and of other stressful, positive, and neutral experiences they reported. We also measured the psychophysiological responses of control participants while they heard the scripts of the abductees. We predicted that if "memories" of alien abduction function like highly stressful memories, then psychophysiological reactivity to the abduction and stressful scripts would be greater than reactivity to the positive and neutral scripts, and this effect would be more pronounced among abductees than among control participants. Contrast analyses confirmed this prediction for all three physiological measures (ps < .05). Therefore, belief that one has been traumatized may generate emotional responses similar to those provoked by recollection of trauma (e.g., combat).

Adult↗

PubMed2003

Prospective evaluation of plasma cortisol in recent trauma survivors with posttraumatic stress disorder.

Hypothalamic pituitary adrenal axis abnormalities have been described in posttraumatic stress disorder (PTSD), and among the recently traumatized. Plasma cortisol and continuous measures of PTSD symptoms were obtained from 21 survivors, at 1 week and 6 months after traumatic events. Eight survivors met Clinician Administered PTSD Scale criteria for PTSD at 6 months. Cortisol levels at 1 week did not predict subsequent PTSD. Survivors with and without PTSD had similar mean levels of cortisol at both time points. Cortisol levels at 6 months negatively correlated with self-reported PTSD symptoms within PTSD subjects.

Adult↗

PubMed2003

Selectively reduced regional cortical volumes in post-traumatic stress disorder.

Different subterritories of anterior cingulate cortex (ACC) and adjacent ventromedial frontal cortex have been shown to serve distinct functions. This scheme has influenced contemporary pathophysiologic models of psychiatric disorders. Prevailing neurocircuitry models of post-traumatic stress disorder (PTSD) implicate dysfunction within pregenual ACC and subcallosal cortex (SC), as well as amygdala and hippocampus. In the current study, cortical parcellation of magnetic resonance imaging data was performed to test for volumetric differences in pregenual ACC and SC, between women with PTSD and trauma-exposed women without PTSD. The PTSD group exhibited selectively decreased pregenual ACC and SC volumes. These results are consistent with contemporary schemes regarding functional and structural dissection of frontal cortex, and suggest specific regional cortical pathology in PTSD.

Cerebral Cortex↗

PubMed2003

Somatic panic-attack equivalents in a community sample of Rwandan widows who survived the 1994 genocide.

The present study is the first to attempt to determine rates of panic attacks, especially 'somatically focused' panic attacks, panic disorder, symptoms of post-traumatic stress disorder (PTSD), and depression levels in a population of Rwandans traumatized by the 1994 genocide. The following measures were utilized: the Rwandan Panic-Disorder Survey (RPDS); the Beck Depression Inventory (BDI); the Harvard Trauma Questionnaire (HTQ); and the PTSD Checklist (PCL). Forty of 100 Rwandan widows suffered somatically focused panic attacks during the previous 4 weeks. Thirty-five (87%) of those having panic attacks suffered panic disorder, making the rate of panic disorder for the entire sample 35%. Rwandan widows with panic attacks had greater psychopathology on all measures. Somatically focused panic-attack subtypes seem to constitute a key response to trauma in the Rwandan population. Future studies of traumatized non-Western populations should carefully assess not only somatoform disorder but also somatically focused panic attacks.

Adolescent↗

PubMed2003

Physiologic responses to sudden, loud tones in monozygotic twins discordant for combat exposure: association with posttraumatic stress disorder.

BACKGROUND: Larger heart rate responses to sudden, loud (startling) tones represent one of the best-replicated psychophysiologic markers for posttraumatic stress disorder (PTSD). This abnormality may be a pretrauma vulnerability factor, ie, it may have been present prior to the event's occurrence and increased the individual's likelihood of developing PTSD on traumatic exposure. Alternately, it may be an acquired PTSD sign, ie, it may have developed after the traumatic exposure, along with the PTSD. Studying identical twins discordant for traumatic exposure offers an opportunity to resolve these competing origins. METHODS: Subjects included pairs of Vietnam combat veterans and their non-combat-exposed, monozygotic twins. Combat veterans were diagnosed as having current PTSD (n = 50) or non-PTSD (ie, never had) (n = 53). All subjects listened to a series of 15 sudden, loud tone presentations while heart rate, skin conductance, and orbicularis oculi electromyogram responses were measured. RESULTS: Consistent with previous reports, averaged heart rate responses to the tones were larger in Vietnam combat veterans with PTSD. These larger responses were not shared by their non-combat-exposed co-twins, whose responses were similar to those of the non-PTSD combat veterans and their non-combat-exposed co-twins. This result remained significant after adjusting for a number of potentially confounding factors. CONCLUSIONS: The results suggest that larger heart rate responses to sudden, loud tones represent an acquired sign of PTSD rather than a familial vulnerability factor.

Acoustic Stimulation↗

PubMed2003

Treatment preferences and determinants in victims of sexual and physical assault.

To determine the treatment preferences (, medication, counseling, or both) for victims of recent trauma at risk for posttraumatic stress disorder and the determinants of those choices, preferences were elicited from 466 consecutive victims of physical or sexual assault at an urban emergency department as part of the routine clinical evaluation by emergency department social workers. Demographics, assault characteristics, and clinical history were used to predict preference. More than 80% of victims expressed an interest in treatment, with more interested in counseling (76%) than medication (62%). Female gender and assaults of a sexual nature were most highly predictive of preference for medication, whereas female gender, sexual assault, a history of psychiatric treatment, and perceived life threat from the trauma were most predictive of preference for counseling and preference for any treatment. Because treatment preferences were easily obtained from assault victims seeking emergency care, the elicitation of these treatment preferences and the consideration of them in the treatment planning process could facilitate engagement in treatment and overcome the avoidance of treatment by some victims.

Adolescent↗

PubMed2002

Performance on visuospatial copying tasks in individuals with chronic posttraumatic stress disorder.

The ability to copy figures was evaluated in 41 subjects with chronic posttraumatic stress disorder (PTSD) and 27 trauma-exposed, non-PTSD comparison subjects. Individuals with PTSD demonstrated significantly impaired performance. However, after adjusting for pre-trauma variables, there was only a marginally significant association between figure-copying performance and PTSD. These findings are consistent with pre-trauma visual-spatial impairment as being among the risk factors for chronic PTSD.

Adult↗

PubMed2002

Absence of selected neurological soft signs in Vietnam nurse veterans with post-traumatic stress disorder.

This study examined eight neurological soft signs (NSSs), which had previously proved successful in discriminating medication-free post-traumatic stress disorder (PTSD) from non-PTSD combat veterans and sexually abused women, in 82 unmedicated female nurse Vietnam veterans, 32 with and 50 without PTSD. The increased NSSs observed in the previously studied PTSD samples were not found in the nurses with PTSD. The results fail to support the hypothesis that the stress of a traumatic event and/or resultant PTSD damages the nervous system.

Attention Deficit Disorder with Hyperactivity↗

PubMed2002

Pilot study of secondary prevention of posttraumatic stress disorder with propranolol.

BACKGROUND: Preclinical considerations suggest that treatment with a beta-adrenergic blocker following an acute psychologically traumatic event may reduce subsequent posttraumatic stress disorder (PTSD) symptoms. This pilot study addressed this hypothesis. METHODS: Patients were randomized to begin, within 6 hours of the event, a 10-day course of double-blind propranolol (n = 18) versus placebo (n = 23) 40 mg four times daily. RESULTS: The mean (SD) 1-month Clinician-Administered PTSD Scale (CAPS) score of 11 propranolol completers was 27.6 (15.7), with one outlier 5.2 SDs above the others' mean, and of 20 placebo completers, 35.5 (21.5), t = 1.1, df = 29, p =.15. Two propranolol patients' scores fell above, and nine below, the placebo group's median, p =.03 (sign test). Zero of eight propranolol, but six of 14 placebo, patients were physiologic responders during script-driven imagery of the traumatic event when tested 3 months afterward, p =.04 (all p values one-tailed). CONCLUSIONS: These pilot results suggest that acute, posttrauma propranolol may have a preventive effect on subsequent PTSD.

Accidents, Traffic↗

PubMed2002

Psychophysiology of post-traumatic stress disorder.

In general, the results of psychophysiologic research on PTSD support the presence of a variety of autonomic, sensory, and cognitive processing differences between individuals with and without the disorder. The findings are diverse and include heightened responsiveness to trauma reminders; exaggerated startle; increased conditionability and autonomic responsiveness to aversive, high-intensity stimuli; and elevated tonic or baseline physiologic activity. Increased sensitivity of the central nervous system is suggested by electrophysiologic evidence for a failure to habituate to redundant information, over-responsiveness to novel information, and reduced cortical responsiveness to overstimulation. Cognitive processing abnormalities are suggested by electrophysiologic evidence for a reduced ability to attend to task-relevant information and increased attention to task-irrelevant, trauma-related information in individuals with PTSD. Some findings, such as the heightened physiologic and P300 response amplitude responses to trauma-related stimuli and increased HR response to loud tones, have been highly replicable and appear to be as reliable as any biologic finding in the psychiatric literature. Other findings, such as increased eye-blink startle responses and tonic or baseline physiologic activity, have been less consistently replicated and have led investigators to explore how stressful or threatening experimental contexts might produce phasic alterations in the psychophysiology of individuals with PTSD. We hope that the broad range of psychophysiologic investigations and findings in PTSD will inspire others to consider possible applications of these methodologies to their own clinical and research endeavors.

Arousal↗

PubMed2002

Event-related potentials to auditory stimuli in female Vietnam nurse veterans with posttraumatic stress disorder.

Individuals with posttraumatic stress disorder (PTSD) have been found to show several event-related brain potential (ERP) abnormalities including reduced target P3b amplitude, P50 suppression, and P2 amplitude/intensity slope. Female Vietnam nurse veterans with (n = 29) and without (n = 38) current PTSD completed P50 paired-click, three-tone "oddball" and four-tone stimulus-intensity modulation procedures. Opposite to previous findings, the current PTSD group had larger target P3b amplitudes and increased P2 amplitude/intensity slopes. Reduced P50 suppression was associated with increased severity of general psychopathology, but not with PTSD diagnosis. Findings suggest that target P3b amplitude and P2 amplitude/intensity slope abnormalities reflect different pathophysiological processes. Future research is needed to determine whether the opposite ERP abnormalities observed in this PTSD sample reflect gender-, trauma-, or sample-specific findings.

Adult↗

PubMed2002

Memory distortion in people reporting abduction by aliens.

False memory creation was examined in people who reported having recovered memories of traumatic events that are unlikely to have occurred: abduction by space aliens. A variant of the Deese/Roediger-McDermott paradigm (J. Deese. 1959; H. L. Roediger III & K. B. McDermott, 1995) was used to examine false recall and false recognition in 3 groups: people reporting recovered memories of alien abduction. people who believe they were abducted by aliens but have no memories, and people who deny having been abducted by aliens. Those reporting recovered and repressed memories of alien abduction were more prone than control participants to exhibit false recall and recognition. The groups did not differ in correct recall or recognition. Hypnotic suggestibility, depressive symptoms, and schizotypic features were significant predictors of false recall and false recognition.

Adult↗