Brain activation in PTSD in response to trauma-related stimuli

Effects of cognitive-behavioral therapy on brain activation in specific phobia

Little is known about the effects of successful psychotherapy on brain function in subjects with anxiety disorders. The present study aimed to identify changes in brain activation following cognitive-behavioral therapy (CBT) in subjects suffering from specific phobia. Using functional magnetic resonance imaging (fMRI), brain activation to spider videos was measured in 28 spider phobic and 14 healthy control subjects. Phobics were randomly assigned to a therapy-group (TG) and a waiting-list control group (WG). Both groups of phobics were scanned twice. Between scanning sessions, CBT was given to the TG. Before therapy, brain activation did not differ between both groups of phobics. As compared to control subjects, phobics showed greater responses to spider vs. control videos in the insula and anterior cingulate cortex (ACC). CBT strongly reduced phobic symptoms in the TG while the WG remained behaviorally unchanged. In the second scanning session, a significant reduction of hyperactivity in the insula and ACC was found in the TG compared to the WG. These results propose that increased activation in the insula and ACC is associated with specific phobia, whereas an attenuation of these brain responses correlates with successful therapeutic intervention.

Central and peripheral psychophysiological responses to trauma-related cues in subclinical posttraumatic stress disorder: a pilot study

This study examined verbal-subjective, peripheral and central physiological responses of motor vehicle accident (MVA) survivors with subclinical posttraumatic stress disorder (PTSD), without PTSD symptoms as well as healthy controls. Seven persons of each group were exposed to positive, neutral, accident-related and negative, non-accident-related slides. The verbal-subjective ratings of the slides did not differ between the groups. In contrast to the verbal ratings of the trauma-related materials, the behavioral and physiological responses showed a remarkable dissociation from these reports. The startle responses were enhanced to accident-related slides only in the PTSD group and MVA survivors with PTSD had a significantly lower response to the neutral slides than MVA survivors without PTSD. P200 was lower to positive, neutral and negative slides in the PTSD group compared to both other groups. The late positive complex showed no group-related effects. The data suggest that traumatized persons with PTSD show exaggerated emotional responses to trauma-related stimuli and reduced cognitive responses to several types of stimuli that may interfere with the extinction of the emotional trauma memory.

Size versus shape differences: contrasting voxel-based and volumetric analyses of the anterior cingulate cortex in individuals with acute posttraumatic stress disorder

BACKGROUND

Two studies found morphological differences in the anterior cingulate cortex (ACC) of individuals with chronic posttraumatic stress disorder (PTSD). We sought to replicate and extend these findings in a sample of individuals with acute PTSD.

METHODS

The ACCs of individuals with acute PTSD (n = 14) and matched healthy control subjects (n = 14) were compared using voxel-based morphometry (VBM), semi-automated volumetric analyses, and probabilistic maps. Posttraumatic stress disorder diagnosis was ascertained by a psychologist using a structured interview.

RESULTS

Voxel-based morphometry analyses revealed significantly less gray-matter density in the right pregenual ACC and in the left insula of the PTSD group. However, volumetric analyses of the ACC revealed no significant differences between groups. Probabilistic maps of the labels of the pregenual ACC indicated that the difference between groups in gray matter density was due to shape differences.

CONCLUSIONS

Although there are no volumetric differences in the ACC of acute PTSD individuals compared with normal control subjects, significant shape differences exist, which might indicate volumetric differences in the surrounding structures.

Context modulation of memory for fear extinction in humans

Distinct memories are formed during fear conditioning and subsequent extinction. In animals, the expression of the latter is gated by the context. The recall of extinction memory after a long delay, and the contextual modulation thereof, has not been directly tested in humans. Mentally healthy volunteers underwent a 2-day fear conditioning and extinction protocol that examined the recall of extinction memory and its relationship to context. Conditioned stimuli were paired with an aversive electric shock in one visual context and extinguished in a different context. Extinction recall and renewal were examined 24 h after training. We found that skin conductance responses were small when the conditioned stimulus was presented in the extinction context, but responses were renewed when the conditioned stimulus was presented in the conditioning context. This finding demonstrates context dependency of extinction recall in humans.

Positron emission tomographic imaging of neural correlates of a fear acquisition and extinction paradigm in women with childhood sexual-abuse-related post-traumatic stress disorder

BACKGROUND

In the conditioned fear paradigm, repeated pairing of an aversive unconditioned stimulus (US) (e.g. electric shock) with a neutral conditioned stimulus (CS) (e.g. bright light) results in a conditioned fear response to the light alone. Animal studies have shown that the amygdala plays a critical role in acquisition of conditioned fear responses, while the medial prefrontal cortex (including anterior cingulate), through inhibition of amygdala responsiveness, has been hypothesized to play a role in extinction of fear responses. No studies have examined neural correlates of fear conditioning and extinction in patients with post-traumatic stress disorder (PTSD).

METHOD

Women with early childhood sexual-abuse-related PTSD (n = 8) and women without abuse or PTSD (n = 11) underwent measurement of psychophysiological (skin conductance) responding as well as positron emission tomographic (PET) measurement of cerebral blood flow during habituation, acquisition and extinction conditions. During habituation subjects were repeatedly exposed to a blue square on a screen. During acquisition, exposure to the blue square (CS) was paired with an electric shock to the forearm (US). With extinction, subjects were again exposed to the blue squares without shock. On a different day subjects went through the same procedure with electric shocks administered randomly in the absence of the blue square.

RESULTS

Skin conductance responding to the CS was consistent with the development of conditioned responses with this paradigm. PTSD patients had increased left amygdala activation with fear acquisition, and decreased anterior cingulate function during extinction, relative to controls.

CONCLUSIONS

These findings implicate amygdala and anterior cingulate in the acquisition and extinction of fear responses, respectively, in PTSD.

Hemodynamic response to emotional memory recall with eye movement

Previous studies on rapid eye movement sleep have demonstrated the effect of eye movement on emotional memory. However, the brain mechanism involved in the influence of the eye movement on the emotional recall remains unclear. We investigated the prefrontal response during an emotional memory recall with and without eye movement. Ten healthy volunteers were recruited. The changes in concentration of oxygenated hemoglobin ([oxy-Hb]) in the prefrontal cortex were examined using near-infrared spectroscopy (NIRS) during a task that involved emotional recall with and without eye movement. Six participants demonstrated a significant increase in [oxy-Hb] during emotional recall, and the level of increase was reduced through repeated emotional recall with eye movement. The results suggest that eye movement is associated with a reduction in the hemodynamic response to emotional memory recall.

Corticolimbic blood flow in posttraumatic stress disorder during script-driven imagery

BACKGROUND

Functional neuroimaging experiments targeting personal recall of emotional events may help elucidate neural substrates underlying posttraumatic stress disorder (PTSD). Studies suggest that limbic and paralimbic function might be altered in PTSD, as compared with trauma-exposed control subjects; however, little is known about functional changes resulting from traumatic experience itself. The present study examined both PTSD-specific and trauma-specific regional cerebral blood flow (rCBF) patterns during script-driven imagery.

METHODS

Sixteen combat veterans with PTSD (PP); 15 combat veterans without PTSD (CC); and 14 healthy, aged-matched noncombat control subjects (NC) underwent [15O] H20 positron emission tomography (PET) scanning during script-driven imagery of emotionally evocative and neutral autobiographic events.

RESULTS

Differential patterns of activation were detected in amygdala and medial frontal cortex. Past trauma experience was associated with decreased amygdala activity (i.e., less activity than healthy control subjects); however, combat control subjects deactivated this region (i.e., greater activity to neutral scripts). All subjects deactivated medial frontal cortex; PTSD patients had greater rostral anterior cingulate (rACC) deactivation compared with control groups, who deactivated ventromedial prefrontal cortex (vmPFC).

CONCLUSIONS

Trauma-specific patterns may represent potential compensatory changes to traumatic reminders, while patterns observed only in the PTSD group may reflect neural substrates specific to PTSD pathophysiology.

Functional connectivity of dissociative responses in posttraumatic stress disorder: a functional magnetic resonance imaging investigation

BACKGROUND

The purpose of this study was to assess interregional brain activity covariations during traumatic script-driven imagery in subjects with posttraumatic stress disorder (PTSD).

METHODS

Functional magnetic resonance imaging and functional connectivity analyses were used to assess interregional brain activity covariations during script-driven imagery in PTSD subjects with a dissociative response, PTSD subjects with a flashback response, and healthy control subjects.

RESULTS

Significant between-group differences in functional connectivity were found. Comparing dissociated PTSD patients and control subjects' connectivity maps in the left ventrolateral thalamus (VLT) [-14, -16, 4] revealed that control subjects had higher covariations between activations in VLT and in the left superior frontal gyrus (Brodmann's area [BA] 10), right parahippocampal gyrus (BA 30), and right superior occipital gyrus (BA 19, 39), whereas greater covariation with VLT in dissociated PTSD subjects occurred in the right insula (BA 13, 34), left parietal lobe (BA 7), right middle frontal gyrus (BA 8), superior temporal gyrus (BA 38, 34), and right cuneus (BA 19). Comparing dissociated PTSD and flashback PTSD connectivity maps in the right cingulate gyrus [3, 16, 30] revealed that dissociated PTSD subjects had higher covariations between activations in this region and the left inferior frontal gyrus (BA 47).

CONCLUSIONS

Greater activation of neural networks involved in representing bodily states was seen in dissociated PTSD subjects than in non-PTSD control subjects. These findings might illuminate the mechanisms underlying distorted body perceptions often observed clinically during dissociative episodes.

Differential time courses and specificity of amygdala activity in posttraumatic stress disorder subjects and normal control subjects

BACKGROUND

Previous neuroimaging studies have demonstrated exaggerated amygdala responses to negative stimuli in posttraumatic stress disorder (PTSD). The time course of this amygdala response is largely unstudied and is relevant to questions of habituation and sensitization in PTSD exposure therapy.

METHODS

We applied blood oxygen level dependent functional magnetic resonance imaging and statistical parametric mapping to study amygdala responses to trauma-related and nontrauma-related emotional words in sexual/physical abuse PTSD and normal control subjects. We examined the time course of this response by separate analysis of early and late epochs.

RESULTS

PTSD versus normal control subjects have a relatively increased initial amygdala response to trauma-related negative, but not nontrauma-related negative, versus neutral stimuli. Patients also fail to show the normal patterns of sensitization and habituation to different categories of negative stimuli. These findings correlate with measured PTSD symptom severity.

CONCLUSIONS

Our results demonstrate differential time courses and specificity of amygdala response to emotional and control stimuli in PTSD and normal control subjects. This has implications for pathophysiologic models of PTSD and treatment response. The results also extend previous neuroimaging studies demonstrating relatively increased amygdala response in PTSD and expand these results to a largely female patient population probed with emotionally valenced words.

Levodopa challenge neuroimaging of levodopa-related mood fluctuations in Parkinson's disease

Some patients with advanced Parkinson's disease (PD) develop dose-related fluctuations in mood. This may reflect alterations in dopamine-influenced brain circuits that mediate emotion. However, there is no available information to localize which dopamine-influenced neurons may be most affected. Eight patients with PD and clinically significant levodopa-related mood fluctuations (mania, depression, or anxiety) were compared to 13 patients with similarly severe PD and fluctuations of motor function but not of mood. Regional cerebral blood flow (rCBF) was measured with positron emission tomography before and after levodopa (in the presence of carbidopa). The rCBF response to levodopa in medial frontal gyrus and posterior cingulate cortex (PCC) significantly differed between mood fluctuators and control patients (corrected p<0.02). Other regions with uncorrected p<0.001 in this comparison were cortical Brodmann areas 22, 40, 13, 11, and 28, hippocampus, and claustrum. The levodopa activation paradigm detected group differences not evident in a comparison of resting rCBF. Abnormalities of dopamine innervation may produce mood fluctuations via effects on PCC, an area strongly linked to mood and anxiety and with known rCBF responsiveness to levodopa or D2-like dopamine receptor agonists. We speculate that mood fluctuations may arise in parkinsonian patients who have abnormal dopaminergic modulation of caudate nucleus, anterior cingulate cortex, or orbital frontal cortex, all of which innervate PCC. The findings require confirmation in larger and better-matched groups.

Effects of traumatic stress on brain structure and function: relevance to early responses to trauma

The events of 9/11 and the widening impact of psychological trauma today have raised a higher level of awareness about the potentially deleterious effects of psychological trauma on the individual. One area of interest after 9/11 was the early trauma response and the most effective way to deal with the window of time immediately after traumatization in order to prevent long term psychopathology. Understanding the neurobiology of the acute trauma response may be useful in designing prevention and treatment strategies. Studies in animals and humans have shown that biological stress response systems, including norepinephrine and cortisol, are affected in both the acute and chronic stages of the trauma response. Brain areas involved in memory, including the hippocampus, amygdala, and prefrontal cortex, may be areas of intervention to ameliorate the early trauma response. Due to the difficulty of performing research in this time period, most research to date has been in patients with chronic disorders such as chronic posttraumatic stress disorder (PTSD). Only a few treatment studies have been performed in the early trauma period, and more research in this area is needed.

Cerebral blood flow changes during script-driven imagery in police officers with posttraumatic stress disorder

BACKGROUND

Functional brain imaging studies in posttraumatic stress disorder (PTSD) have focused mostly on war or sexual abuse victims, many of whom also had comorbid disorders. The aim of this study was to examine the neuronal circuitry underlying responses to script-driven imagery in traumatized police officers with and without PTSD and with low comorbidity rates.

METHODS

In a case-matched control study, 30 traumatized police officers with and without PTSD underwent clinical assessment and (99m)technetium-hexa-methyl-propylene-amine-oxime single photon emission computed tomography scanning with neutral and trauma scripts. Statistical parametric mapping was applied to analyze changes in regional cerebral blood flow.

RESULTS

The main findings were significantly less activation in the medial frontal gyrus and more activation in the right cuneus in the PTSD group relative to the trauma-exposed control group in reaction to trauma versus neutral scripts. Within the PTSD group, subjects showed less activation in the superior temporal gyrus, left lentiform nucleus, left middle frontal gyrus, and left inferior frontal gyrus in reaction to trauma scripts.

CONCLUSIONS

We confirmed previous findings of dysfunction of the medial frontal gyrus in PTSD in a new population with low comorbidity rates. Other alterations were found in certain brain structures involved in emotional, memory, linguistic, visuospatial, and motor processing.

Dimensional complexity of the EEG in patients with posttraumatic stress disorder

Recent electrophysiological studies have reported evidence of information processing abnormalities in patients with posttraumatic stress disorder (PTSD). The aim of this study is to examine dynamical complexity of the EEG in PTSD patients, which is thought to reflect information processing of the brain. Resting EEG recordings (32,800 data points acquired continuously from 82 s of an EEG record) were obtained in 16 channels of 27 patients with PTSD from a mixed civilian trauma population and 14 healthy subjects. The correlation dimension (D2) of the EEG was used to quantify the complexity of the cortical dynamics underlying the EEG signal. The PTSD patients were found to have lower D2 values than those of the healthy subjects in most channels (Fp1, F8, C4, P4, T3, T4, T5, T6, and O1), indicating that PTSD patients have globally reduced complexity in their EEG waveforms. This study supports the hypotheses that PTSD patients exhibit disturbed cortical information processing, and that non-linear dynamical analysis of the EEG can be a tool for detecting changes in neurodynamics of the brain in PTSD.

Adaptive and maladaptive psychobiological responses to severe psychological stress: implications for the discovery of novel pharmacotherapy

Post-traumatic stress disorder (PTSD) is one of the few DSM-IV diagnoses contingent upon a psychosocial stressor. In this context, there is an urgent need to acquire a better understanding of both the adaptive and maladaptive psychobiological responses to traumatic stress. Preclinical investigators have utilized a variety of animal models to identify the behavioral and neurobiological features of the organism's response to stress. However, given the complexity of the healthy and pathological human response to physiological and psychological stress, the extent to which the animal data is immediately transferable to human remains to be fully determined. This review draws upon preclinical and clinical literature to examine the transformation of an adaptive human stress response into a maladaptive and debilitating mental disorder. An integrative psychobiological model for PTSD is presented, linking psychological processes and behavioral patterns with current findings in neurocircuitry, neurochemistry and psychophysiology. The implications of this model for the discovery of novel pharmacological approaches to the treatment of severe psychological distress are discussed.

Temperament and its implications for neuroimaging of anxiety disorders

We review the attributes of inhibited and uninhibited infant temperaments, and their developmental trajectories into early adulthood. Inborn individual differences in infants' propensity to respond to novel people and objects are associated with persistent differences in the responsivity of the amygdala to novelty, as measured with functional magnetic resonance imaging, after more than 20 years of development. Because an inhibited temperament is a risk factor for developing later psychiatric disorders, particularly generalized social anxiety disorder, temperamental differences are confounds in neuroimaging and genetic studies. Longitudinal studies are a unique tool for understanding the developmental and temperamental risk factors for psychiatric disorder.

A positron emission tomography study of memories of childhood abuse in borderline personality disorder

BACKGROUND

Borderline personality disorder (BPD) is a common psychiatric disorder, which is linked to early stressors in many cases; however, the impact of traumatic events in the etiology of BPD is still unclear. This pilot study was conducted to measure the neural correlates of recall of traumatic memories in women with and without BPD.

METHODS

Twenty women with a history of childhood physical or sexual abuse underwent measurement of brain blood flow with positron emission tomography imaging while they listened to scripts describing neutral and personal traumatic abuse events. Brain blood flow during exposure to trauma and neutral scripts was compared between women with and without BPD.

RESULTS

Memories of trauma were associated with increases in blood flow in right dorsolateral prefrontal cortex (Brodmann's area [BA] 44 and 45) and with decreased blood flow in left dorsolateral prefrontal cortex (BA 44 and 45) in women without BPD. There was also increased blood flow in right anterior cingulate (BA 24) and left orbitofrontal cortex (BA 11) in women without BPD. Women with BPD failed to activate anterior cingulate gyrus and orbitofrontal cortex. Also, no blood flow changes were seen in dorsolateral prefrontal gyrus in women with BPD.

CONCLUSIONS

Dysfunction of dorsolateral and medial prefrontal cortex, including anterior cingulate, seems to be correlated with the recall of traumatic memories in women with BPD. These brain areas might mediate trauma-related symptoms, such as dissociation or affective instability, in patients with BPD.

Topiramate attenuates exaggerated acoustic startle in an animal model of PTSD

RATIONALE

Exaggerated acoustic startle is a prominent symptom of post-traumatic stress disorder (PTSD); however, its physiological basis is not well understood, and there are few available treatments. Neurobiological research has suggested that anti-kindling agents and/or glutamate antagonists can attenuate the acoustic startle response (ASR) in animal models. The anticonvulsant topiramate is an AMPA antagonist that also demonstrates potent anti-kindling effects and may, therefore, have promise in treating trauma-enhanced ASR.

OBJECTIVE

To evaluate the ability of topiramate to attenuate stress-induced increases in ASR in a previously validated animal model of PTSD.

METHODS

Male Sprague-Dawley rats ( n=36) served as controls or received single prolonged stress (SPS). SPS consisted of 2 h restraint, forced swim and ether anesthesia, then a 7-day "undisturbed" period. Animals then received vehicle, 10 mg/kg or 30 mg/kg of topiramate orally, twice daily for 7 days. ASR was assessed for all animals before and after the study, in light and dark environments.

RESULTS

SPS produced a sustained increase in the ASR in both environments, an effect that was significantly reduced by topiramate. Meanwhile the ASR of control animals remained unaffected by topiramate.

CONCLUSIONS

The current results provide one of the few demonstrations of a single stress episode producing sustained enhancement of ASR. In addition, topiramate demonstrates promise in treating exaggerated acoustic startle symptoms in PTSD or other stress-related disorders.

Adaptations or pathologies? Long-term changes in brain and behavior after a single exposure to severe threat

The experience of a single threatening situation may alter the behavior of an animal in a long-lasting way. Long-lasting changes in behavior have been induced in laboratory animals to model and investigate the development and neural substrate of human psychopathologies. Under natural conditions, however, changes in behavior after an aversive experience may be adaptive because behavioral modifications allow animals to adjust to a threat for extended periods of time. In the laboratory setting, properties of the aversive situation and the potential of the animal to respond to the threat may be altered and lead to extensive, prolonged changes, indicating a failure in behavioral regulation. Such long-term changes seem to be mediated by neuronal alterations in components of the fear pathway. To understand psychopathologies, determinants of exaggerated responsivity and the underlying molecular and neural processes have to be analyzed in a comparative way under conditions that produce normal and abnormal fear and anxiety.

Effects of cannabidiol (CBD) on regional cerebral blood flow

Animal and human studies have suggested that cannabidiol (CBD) may possess anxiolytic properties, but how these effects are mediated centrally is unknown. The aim of the present study was to investigate this using functional neuroimaging. Regional cerebral blood flow (rCBF) was measured at rest using (99m)Tc-ECD SPECT in 10 healthy male volunteers, randomly divided into two groups of five subjects. Each subject was studied on two occasions, 1 week apart. In the first session, subjects were given an oral dose of CBD (400 mg) or placebo, in a double-blind procedure. SPECT images were acquired 90 min after drug ingestion. The Visual Analogue Mood Scale was applied to assess subjective states. In the second session, the same procedure was performed using the drug that had not been administered in the previous session. Within-subject between-condition rCBF comparisons were performed using statistical parametric mapping (SPM). CBD significantly decreased subjective anxiety and increased mental sedation, while placebo did not induce significant changes. Assessment of brain regions where anxiolytic effects of CBD were predicted a priori revealed two voxel clusters of significantly decreased ECD uptake in the CBD relative to the placebo condition (p<0.001, uncorrected for multiple comparisons). These included a medial temporal cluster encompassing the left amygdala-hippocampal complex, extending into the hypothalamus, and a second cluster in the left posterior cingulate gyrus. There was also a cluster of greater activity with CBD than placebo in the left parahippocampal gyrus (p<0.001). These results suggest that CBD has anxiolytic properties, and that these effects are mediated by an action on limbic and paralimbic brain areas.

Functional connectivity of the prefrontal cortex and the amygdala in posttraumatic stress disorder

BACKGROUND

Persistent, intrusive re-experiencing in posttraumatic stress disorder (PTSD) is commonly construed as a failure of cingulate inhibition (i.e., extinction) over a hyperresponsive amygdala, based primarily on animal research of fear conditioning and the finding of cingulate hypoperfusion in PTSD.

METHODS

We examined functional connectivity in patients with PTSD and healthy trauma survivors during repeated symptom provocation using H(2)O(15) positron emission tomography.

RESULTS

Memory retrieval networks (right prefrontal cortex, hippocampus, and visual cortex) were common to both groups. Networks supporting autonomic and emotional control and preparatory motor action (amygdala, anterior cingulate, subcallosal gyrus, and premotor cortex) differed between the two groups and became progressively disparate with successive presentations of the traumatic script. Patterns of effective connectivity demonstrated the predominance of direct influences of the amygdala on visual cortex, subcallosal gyrus, and anterior cingulate in PTSD but not in control subjects. There was little evidence for failure of inhibition of cingulate or subcallosal cortex over the amygdala.

CONCLUSIONS

These patterns might represent excessive influences of the amygdala over regions involved in autonomic, and higher-order visual memory processing in PTSD. The present data suggest that inferences of direct correspondence between animal studies and pathophysiology of PTSD should be made with caution.

Affective neuroscience and psychophysiology: toward a synthesis

This article reviews the author's program of research on the neural substrates of emotion and affective style and their behavioral and peripheral biological correlates. Two core dimensions along which affect is organized are approach and withdrawal. Some of the key circuitry underlying approach and withdrawal components of emotion is reviewed with an emphasis on the role played by different sectors of the prefrontal cortex (PFC) and amygdala. Affective style refers to individual differences in valence-specific features of emotional reactivity and regulation. The different parameters of affective style can be objectively measured using specific laboratory probes. Relations between individual differences in prefrontal and amygdala function and specific components of affective style are illustrated. The final section of the article concludes with a brief discussion of plasticity in the central circuitry of emotion and the possibility that this circuitry can be shaped by training experiences that might potentially promote a more resilient, positive affective style. The implications of this body of work for a broader conception of psychophysiology and for training the next generation of psychophysiologists are considered in the conclusion.

Neuroanatomical circuits modulating fear and anxiety behaviors

OBJECTIVE

Our understanding of the neurobiology of anxiety disorders, although not complete, has advanced significantly with the development and application of genetic, neuroimaging and neurochemical approaches.

METHOD

The neuroanatomical basis of anxiety disorders is reviewed with particular focus on the amygdala and the temporal and prefrontal cortex. The functional anatomical correlates of anxiety disorders such as panic disorder, specific phobias and post-traumatic stress disorder are also discussed.

RESULTS

Functional neuroimaging studies in patients with anxiety disorders have shown neurophysiological abnormalities during symptom provocation tests, implicating the limbic, paralimbic and sensory association regions. The involvement of neurotransmitters such as serotonin and norepinephrine in depressive disorders is well established. Antidepressants that affect these neurotransmitter systems have also been shown to be useful in the treatment and management of patients with anxiety disorders. The role of serotonin and norepinephrine in the pathophysiology of anxiety disorders is reviewed. In addition, the involvement of the stress hormone corticotropin-releasing hormone, the peptide cholecystokinin and the amino acid transmitter gamma-amino butyric acid in anxiety disorders is reviewed.

CONCLUSION

The inconsistency in the results of biologic investigations of anxiety disorders highlights the importance of addressing the neurobiologic heterogeneity inherent within criteria-based, psychiatric diagnoses. Understanding of this heterogeneity will be facilitated by the continued development and application of genetic, neuroimaging and neurochemical approaches that can refine anxiety disorder phenotypes and elucidate the genotypes associated with these disorders. Application of these experimental approaches will also facilitate research aimed at clarifying the mechanisms of anti-anxiety therapies.

Brain environment interactions: stress, posttraumatic stress disorder, and the need for a postmortem brain collection

Stress, especially the extreme stress of traumatic events, can alter both neurobiology and behavior. Such extreme environmental situations provide a useful model for understanding environmental influences on human biology and behavior. This paper will review some of the evidence of brain alterations that occur with exposure to environmental stress. This will include recent studies using neuroimaging and will address the need for histological confirmation of imaging study results. We will review the current scientific approaches to understanding brain environment interactions, and then make the case for the collection and study of postmortem brain tissue for the advancement of our understanding of the effects of environment on the brain. Creating a brain tissue collection specifically for the investigation of the effects of extreme environmental stressors fills a gap in the current research; it will provide another of the important pieces to the puzzle that constitutes the scientific investigation of negative effects of environmental exposures. Such a resource will facilitate new discoveries related to the psychiatric illnesses of acute stress disorder and posttraumatic stress disorder, and can enable scientists to correlate structural and functional imaging findings with tissue abnormalities, which is essential to validate the results of recent imaging studies.

Psychotherapy as assisted homeostasis: activation of emotional processing mediated by the anterior cingulate cortex

Although psychotherapy is successful in altering emotional distress, the biological mechanism by which it achieves this has not been the subject of intensive neurobiological investigation. Mindful processing of emotion has been proposed [Mindfulness-Based Cognitive Therapy for Depression, The Guilford Press, New York, 2002] to be a key factor in prevention of relapse in depressive illness and here that hypothesis is developed and extended to include other conditions in which emotion processing may be obstructed or dysregulated. Cognitive therapy, interpersonal psychotherapy, psycho-dynamic psychotherapy and dialectical behaviour therapy, each in a different way and with a distinct emphasis, encourage awareness of emotions and their associated cognitions and biographies, and their varying success may depend on the degree to which they achieve activation of internal healing processes. In eye movement desensitisation and reprocessing (EMDR), the selected target is formatted for endogenous processing which is facilitated and accelerated by eye movements or alternating bilateral auditory or tactile stimulation. The ability to sustain focussed attention on the affect and its visceral, cognitive and biographical components is postulated to activate a homeostatic process of distress resolution, seen most clearly in treatment of post-traumatic stress disorder (PTSD) with EMDR, in which resolution of distress can be intense and rapid while therapist input is non-directive, although supportive, empathic, and non-judgemental. Once the therapist has helped to frame the questions, the patient's brain will find the answers needed for the resolution of the distress and all the components of the traumatic event, whether visceral, cognitive, affective or interpersonal. The anterior cingulate cortex, especially the dorsal and rostral components, is suggested to be the key neurobiological substrate for the efficacious psychotherapeutic relief of distress, and relevant functional neuroimaging studies are summarised. One limitation of some previous imaging studies of emotion is that they have tended to use mild stimuli to discrete emotions. An alternative approach would be to image the brain during reprocessing of an unpleasant event which has profoundly affected the person so that the associated intense emotions could be clearly labelled and correlated with changes in regional brain functioning.

Cortical neurophysiology of anticipatory anxiety: an investigation utilizing steady state probe topography (SSPT)

The precise role of the cortex in human anxiety is not well characterised. Previous imaging research among healthy controls has reported alterations in regional cerebral blood flow (rCBF) within the prefrontal and temporal cortices during periods of anxious anticipation; however, the temporal dynamics of this activity has yet to be examined in detail. The present study examined cortical Steady State Probe Topography (SSPT) changes associated with anticipatory anxiety (AA), allowing examination of the temporal continuity and the excitatory or inhibitory nature of AA activations. We recorded Steady State Visually Evoked Potentials (SSVEPs) at 64 scalp locations, skin conductance, and self reported anxiety among 26 right-handed males while relaxed and during the anticipation of an electric shock. Relative to the baseline condition, the AA condition was associated with significantly higher levels of self-reported anxiety and increased phasic skin conductance levels. Across the seven second imaging window, AA was associated with increased SSVEP latency within medial anterior frontal, left dorsolateral prefrontal and bilateral temporal regions. In contrast, increased SSVEP amplitude and decreased SSVEP latency were observed within occipital regions. The observed SSVEP latency increases within frontal and temporal cortical regions are suggestive of increased localised inhibitory processes within regions reciprocally connected to subcortical limbic structures. Occipital SSVEP latency decreases are suggestive of increased excitatory activity. SSVEP amplitude increases within occipital regions may be associated with an attentional shift from external to internal environment. The current findings provide further support for the involvement of frontal, anterior temporal, and occipital cortical regions during anticipatory anxiety, and suggest that both excitatory and inhibitory processes are associated with AA alterations.

Amygdala and insular responses to emotionally valenced human faces in small animal specific phobia

BACKGROUND

Contemporary neurobiological models suggest that the amygdala plays an important role in the pathophysiology of anxiety disorders. However, it is not clear to what extent this concept applies across anxiety disorders. Several studies have examined brain function in specific phobias but did not demonstrate amygdala responses or use specific probes of the amygdala.

METHODS

Ten subjects with specific small animal phobia and 10 matched control subjects were studied with functional magnetic resonance imaging. Subjects viewed emotionally expressive and neutral faces, and amygdala blood oxygenation level dependent responses from each group were compared.

RESULTS

There was a significant response to the fearful versus neutral faces in the amygdala across both groups but no diagnosis x condition interaction. Post hoc analysis of the whole brain revealed a significantly greater response to the fearful versus neutral faces in the right insular cortex of the specific phobia group than in the control group.

CONCLUSIONS

Amygdala hyperresponsivity to emotional faces was not observed in subjects with small animal specific phobia, in contrast to findings in other anxiety disorders (e.g., posttraumatic stress disorder). This suggests a restricted role for the amygdala in specific phobia. The insular hyperresponsivity to fearful versus neutral faces in the subjects with specific phobias warrants further study.

Resting regional cerebral perfusion in recent posttraumatic stress disorder

BACKGROUND

Brain imaging research in posttraumatic stress disorder has been largely performed on patients with chronic disease, often heavily medicated, with current or past alcohol and substance abuse. Additionally, virtually only activation brain imaging paradigms have been done in posttraumatic stress disorder, whereas in other mental disorders both resting and activation studies have been performed.

METHODS

Twenty-eight (11 posttraumatic stress disorder) trauma survivors underwent resting state hexamethylpropyleneamineoxime single photon emission computed tomography and magnetic resonance imaging 6 months after trauma. Eleven nontraumatized subjects served as healthy controls.

RESULTS

Regional cerebral blood flow in the cerebellum was higher in posttraumatic stress disorder than in both control groups. Regional cerebral blood flow in right precentral, superior temporal, and fusiform gyri in posttraumatic stress disorder was higher than in healthy controls. Cerebellar and extrastriate regional cerebral blood flow were positively correlated with continuous measures of depression and posttraumatic stress disorder. Cortisol level in posttraumatic stress disorder was negatively correlated with medial temporal lobe perfusion. Anterior cingulate perfusion and cortisol level were positively correlated in posttraumatic stress disorder and negatively correlated in trauma survivors without posttraumatic stress disorder.

CONCLUSIONS

Recent posttraumatic stress disorder is accompanied by elevated regional cerebral blood flow, particularly in the cerebellum. This warrants attention because the cerebellum is often used as a reference region in regional cerebral blood flow studies. The inverse correlation between plasma cortisol and medial temporal lobe perfusion may herald hippocampal damage.

Neuroimaging and neurocircuitry in post-traumatic stress disorder: what is currently known?

Neurobiologic, psychologic, and social factors interact jointly to create and perpetuate the symptoms of post-traumatic stress disorder (PTSD). The fear conditioning paradigm in animal research helped researchers gather preclinical evidence for the possible contribution of several brain areas to PTSD symptoms. In the past 10 years, highly sophisticated neuroimaging techniques made it possible for researchers to look at the brain of patients with PTSD and draw conclusions about the neurocircuitry underlying PTSD symptoms. In this article, the author will review the evidence from neuroimaging studies for the involvement of the following brain areas in PTSD neurocircuitry: the amygdala, the anterior cingulate cortex and subcallosal gyrus, the inferior frontal gyrus, the posterior cingulate cortex, and the hippocampus. Neuroimaging studies have shown these areas as altered in structure or function in patients with PTSD. The author also presents the normal functions that these areas subserve and, whenever possible based on the evidence, infer how their dysfunction may contribute importantly to the symptomatology of PTSD.

A volumetric study of amygdala in cancer survivors with intrusive recollections

BACKGROUND

Intrusive recollections, one of the re-experiencing symptoms of posttraumatic stress disorder (PTSD), frequently occur in cancer survivors rather than the full spectrum of the symptoms of PTSD. Functional neuroimaging studies of PTSD have revealed hyperresponsiveness to threat-related stimuli in the amygdala, but no volumetric studies have ever found alteration in the volume of the amygdala. The aim of the present study was to assess the possibility of structural alteration of the amygdala in cancer survivors with intrusive recollections.

METHODS

Magnetic resonance imaging volumetric analysis of the amygdala was performed in 35 breast cancer survivors with a history of cancer-related intrusive recollections and 41 control breast cancer survivors who had no such history. The groups were similar in age, height, handedness, alcohol consumption, and medical characteristics except for past major depressive disorder.

RESULTS

The total volume of the amygdala was significantly smaller in subjects with a history of intrusive recollections as compared with the control subjects. This finding continued to be significant after controlling for age, height, and major depressive disorder.

CONCLUSIONS

These results suggest a difference in volume of the amygdala of cancer survivors according to whether they have had cancer-related intrusive recollections.

Brain-imaging studies of posttraumatic stress disorder

Brain-imaging studies of posttraumatic stress disorder (PTSD) have rapidly increased in recent years. Structural studies have identified potential smaller volumes of the hippocampus of traumatized and/or PTSD subjects. Functional activation studies have implicated hyperactive or altered functioning of brain regions, such as the amygdala and the insula, and a failure to engage emotional regulatory structures, such as the medial prefrontal and anterior cingulate cortex. Recent neurochemical investigations have suggested that neuromodulatory systems (eg, gamma-aminobutyric acid, micro-opioid) may underlie these aberrant brain activation patterns. This article reviews the literature on structural, functional, and neurochemical brain-imaging studies of PTSD.

Neurocircuitry of anxiety disorders

A major focus in the field of anxiety in the past decade, and an area of intense ongoing interest, is the delineation of the basic neurocircuitry underlying normal and pathologic anxiety. Preclinical work defining the basic neurocircuitry responsible for fear responding has fueled neuroimaging investigations attempting to model the neurocircuitry of the anxiety disorders. Herewith, the authors review neuroimaging findings contributing to the development and refinement of neuroanatomic models for post-traumatic stress disorder, panic disorder, and social anxiety disorder.

Dog phobia in a motion-blind patient

INTRODUCTION

A prominent neurophysiological model of phobia generation holds that specific phobia might result from the uncoupling of unaware subcortical fear responses from aware cortical fear responses. Former responses are thought to be automatic and fast, providing approximate information about the external stimulus, whereas the latter responses are more controlled and allow comparison with previous experience. Since only the cortical pathway carries information available to awareness, this model also accounts for the striking irrationality of specific phobia in humans.

METHODS

Here, we report neuropsychological and neuro-ophthalmological findings in a 41-year-old patient who developed severe dog phobia following bilateral parietal lobe damage.

RESULTS

The examinations showed a severe deficit in visual motion perception (visual motion blindness or akinetopsia) as well as spatial vision. Importantly, the patient was largely unaware of his visual deficits.

CONCLUSION

Based on the present observation it is argued that irrational fear, as found in specific phobia, might not only result from a general uncoupling of aware cortical from unaware subcortical fear responses, but also from a functionally similar dissociation at the cortical level.

Behavioral aspects of trauma in children and youth

Trauma is prevalent in the lives of children. It derives from many sources, and, depending on its characteristics, can produce transient or enduring and devastating consequences. Early trauma, if left untreated, can set the stage for chronic deficits in the behavioral repertoires of affected children, and thus shape personality development. Additionally, when trauma is repetitive and chronic, the developing brain may be affected in ways that impede otherwise effective intervention. Yet diagnosing traumatic stress in children requires a departure from exclusively adult-like considerations and attention must be devoted to the ongoing developmental processes. Trauma-associated clinical features in children are sharply distinct from those that are associated with adult traumatization and must be taken into account from screening and diagnosis through treatment and outcome evaluation. We suggest that a learning foundation for symptom development will best assist the identification and selection of efficacious treatments. Pediatricians should make use of validated screening procedures that effectively identify affected children to facilitate timely referral and ongoing monitoring of treatment outcomes for their patients. A representative list of such instruments can be found in Table 1. With respect to hospital-based trauma work, we suggest the following recommendations: Professionals must be alert to the presence of acute stress symptoms in any child or parent after all injury incidents. These symptoms may occur in any injured child regardless of age, gender, injury severity, mechanism of injury, or length of time since injury. Certain mechanisms of injury, (ie, pedestrian versus motor vehicle collision), place the parent at higher risk for symptomatology. All family members, including parents and siblings, must be considered at risk for acute and long-term functional abnormalities. It is important to educate patients and family members that acute stress symptoms are common after an injury incident and are likely to resolve as the patient's injuries heal. Yet despite this, before discharge from the hospital, parents must be taught to evaluate their traumatized child's behavior, as well as their own, for any evidence of posttraumatic stress disorder. Health care providers must anticipate potential strain upon family relationships and financial resources. Parent's posttraumatic stress symptoms may result in deterioration of their own ability to support their injured child. And finally, reassessment of patient and family members should occur within the first days, at 1 to 2 weeks, 6 months, and 1 year following injury to ensure proper recovery and optimization of psychosocial function.

Serotonin type II receptor activation facilitates synaptic plasticity via N-methyl-D-aspartate-mediated mechanism in the rat basolateral amygdala

The modulation of synaptic plasticity by serotonin type II (5-hydroxytryptamine type II (5-HT(2)))-receptor stimulation was explored using intracellular, field potential and Fura-2 fluorescence image recordings in a rat amygdala slice preparation. Bath application of 5HT(2) receptor agonist 1-(2,5)-dimethoxy-4-iodophen-2-aminopropane (DOI) transformed theta-burst-stimulated (TBS) synaptic plasticity from short-term potentiation to long-term potentiation. DOI enhanced N-methyl-D-aspartate (NMDA) receptor-mediated potentials and calcium influx without affecting the resting membrane potential or input resistance of the neurons. In contrast, alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA)/kainate receptor-mediated excitatory synaptic responses were unaffected by DOI. The facilitating effects of DOI were blocked by the 5-HT(2) receptor antagonist, ketanserin, and by the 5-HT(2C)-receptor selective antagonist, RS102221. These results indicate that 5-HT(2)-receptor activation enhances NMDA receptor-mediated synaptic function in the basolateral amygdala (BLA).

Neural correlates of memories of abandonment in women with and without borderline personality disorder

BACKGROUND

Borderline personality disorder (BPD) is a common psychiatric disorder that is often linked to early stressors. One particularly salient feature of the disorder is fear of abandonment. This pilot study was conducted to measure neural correlates of memories of abandonment in women with and without BPD.

METHODS

Twenty women with a history of childhood sexual abuse underwent measurement of brain blood flow with positron emission tomography imaging while they listened to scripts describing neutral and personal abandonment events. Brain blood flow during exposure to abandonment and neutral scripts was compared among women with and without BPD.

RESULTS

Memories of abandonment were associated with greater increases in blood flow in bilateral dorsolateral prefrontal cortex (middle frontal gyrus, Brodmann's areas 9 and 10) as well as right cuneus (area 19) in women with BPD than in women without BPD. Abandonment memories were associated with greater decreases in right anterior cingulate (areas 24 and 32) in women with BPD than in women without BPD.

CONCLUSIONS

These findings implicate dysfunction of dorsolateral and medial prefrontal cortex including anterior cingulate, left temporal cortex, and visual association cortex in memories of abandonment in women with BPD. These brain areas may mediate symptoms of BPD.

Activation of the prefrontal cortex to trauma-related stimuli measured by near-infrared spectroscopy in posttraumatic stress disorder due to terrorism

To develop a noninvasive method for psychophysiological assessment of posttraumatic stress disorder (PTSD), 34 victims of the Tokyo Subway Sarin Attack in 1995 including 8 diagnosed as PTSD and 12 controls were examined by a multichannel near-infrared spectroscopy (NIRS) system. Hemodynamic response in the prefrontal cortex was monitored during the presentation of trauma-related and control stimuli by video images. Skin conductance response (SCR) was also examined. Oxygenated hemoglobin significantly increased during the trauma-related image in the victims with or without PTSD. Deoxygenated hemoglobin significantly decreased only in victims with PTSD. No significant alteration was found in controls. Significantly enhanced SCR was also observed in the victims with PTSD during trauma-related stimuli. The findings suggest that measurement of cerebral hemodynamic response by NIRS is useful for psychophysiological assessment of PTSD.

Sensing the invisible: differential sensitivity of visual cortex and amygdala to traumatic context

To what extent does emotional traumatic context affect sensory processing in the brain? A striking example of emotional impact on sensation is manifested in posttraumatic stress disorder (PTSD), in which a severe emotional trauma produces recurrent and vivid unpleasant sensory recollections. Here we report on an fMRI study exploring the sensory processing of trauma-related pictures in the visual cortex and amygdala in respect to PTSD. The impact of traumatic experience on brain responses was tested in relation to stimuli content and its level of recognition in a parametric factorial design. Twenty combat veterans, 10 with and 10 without PTSD, viewed backward-masked images of combat and noncombat content, presented at below, near, and above recognition thresholds. The response to combat content evoked more activation in the visual cortex in PTSD subjects than in non-PTSD subjects, only when images were presented at below recognition threshold. By contrast, the amygdala demonstrated increased activation in PTSD subjects irrespective of content and recognition threshold of the images. These intriguing findings are compatible with the notion that in PTSD, emotional traumatic experience could modify visual processing already at the preattentive level. On the other hand, lack of content specificity in the amygdala point to a possible predisposed mechanism for pathological processing of traumatic experience. The differential sensitivity of the amygdala and visual cortex to traumatic context implies distinct roles of limbic and sensory regions in the registration and recollection of emotional experience in the brain.

Differential amygdalar response to novel versus newly familiar neutral faces: a functional MRI probe developed for studying inhibited temperament

BACKGROUND

As a prelude to future studies of subjects with different temperaments, we sought to develop a probe to measure differential amygdalar responses to novel versus familiar stimuli. Prior neuroimaging studies of the amygdala in humans to date have focused principally on responses to emotional stimuli, primarily aversive, rather than to novelty per se.

METHODS

Eight normal subjects aged 22.4 +/- 1.3 years were scanned using functional magnetic resonance imaging (fMRI) during passive viewing of novel and familiar faces.

RESULTS

Using this newly developed paradigm, we found greater fMRI blood oxygenation level dependent (BOLD) signal response within the right amygdala to novel versus familiar faces--all with neutral expression. Furthermore, although a new facial identity was always presented in the novel condition, signal in the amygdala declined over time as it did for the familiar condition.

CONCLUSIONS

These results suggest that at least one primary function of the amygdala is to detect and process unexpected or unfamiliar events that have potential biological import, of which stimuli symbolic of fear or threat are but one possible example. We propose that this experimental paradigm will be useful for examining brain responses to novelty in different temperamental groups, as well as various psychiatric disorders.

Neural correlates of declarative memory for emotionally valenced words in women with posttraumatic stress disorder related to early childhood sexual abuse

BACKGROUND

Animal studies have shown that early stressors result in lasting changes in structure and function of brain areas involved in memory, including hippocampus and frontal cortex. Patients with childhood abuse-related posttraumatic stress disorder (PTSD) have alterations in both declarative and nondeclarative memory function, and imaging studies in PTSD have demonstrated changes in function during stimulation of trauma-specific memories in hippocampus, medial prefrontal cortex, and cingulate. The purpose of this study was to assess neural correlates of emotionally valenced declarative memory in women with early childhood sexual abuse and PTSD.

METHODS

Women with early childhood sexual abuse-related PTSD (n = 10) and women without abuse or PTSD (n = 11) underwent positron emission tomographic (PET) measurement of cerebral blood flow during a control condition and during retrieval of neutral (e.g., "metal-iron") and emotionally valenced (e.g., "rape-mutilate") word pairs.

RESULTS

During retrieval of emotionally valenced word pairs, PTSD patients showed greater decreases in blood flow in an extensive area, which included orbitofrontal cortex, anterior cingulate, and medial prefrontal cortex (Brodmann's areas 25, 32, 9), left hippocampus, and fusiform gyrus/inferior temporal gyrus, with increased activation in posterior cingulate, left inferior parietal cortex, left middle frontal gyrus, and visual association and motor cortex. There were no differences in patterns of brain activation during retrieval of neutral word pairs between patients and control subjects.

CONCLUSIONS

These findings are consistent with dysfunction of specific brain areas involved in memory and emotion in PTSD. Regions implicated in this study of emotionally valenced declarative memory are similar to those from prior imaging studies in PTSD using trauma-specific stimuli for symptom provocation, adding further supportive evidence for a dysfunctional network of brain areas involved in memory, including hippocampus, medial prefrontal cortex, and cingulate, in PTSD.

Neuroimaging studies of amygdala function in anxiety disorders

Neuroimaging research has helped to advance neurobiological models of anxiety disorders. The amygdala is known to play an important role in normal fear conditioning and is implicated in the pathophysiology of anxiety disorders. The amygdala may also be a target for the beneficial effects of cognitive-behavioral and medication treatments for anxiety disorders. In the current paper, we review neuroimaging research pertaining to the role of the amygdala in anxiety disorders and their treatment. Moreover, we discuss the development of new neuroimaging paradigms for measuring aspects of amygdala function, as well as the function of related brain regions. We conclude that such tools hold great promise for facilitating progress in relevant basic neuroscience as well as clinical research domains.

Amygdaloid regional cerebral blood flow and subjective fear during symptom provocation in anxiety disorders

Whether the amygdala is involved predominantly in emotional perception or in the generation of emotional states has been debated. We reviewed and reanalyzed data from our laboratory, indicating that subjective feelings of fear and distress are correlated with regional cerebral blood flow (rCBF) in the right but not the left amygdala during anxiety provocation in individuals with social anxiety disorder, specific phobias. and posttraumatic stress disorder. Positron emission tomography is a correlative technique, and casual inferences cannot be drawn. However, because studies demonstrate that treatment of social anxiety disorder with cognitive behavior therapy and selective serotonin reuptake inhibitors results in reduced rCBF in the amygdaloid complex and prospective studies reveal that treatment-induced alterations in amygdala rCBF can predict 1 year follow-up status in social anxiety disorder data support the notion that the amygdala, at least in part, seem casually involved in generating the subjective experience of fear.

Cerebral function in posttraumatic stress disorder during verbal working memory updating: a positron emission tomography study

BACKGROUND

This study examined cerebral function in posttraumatic stress disorder (PTSD) during the updating of working memory to trauma-neutral, verbal information.

METHODS

Ten PTSD and matched control subjects completed a visuoverbal target detection task involving continuous updating (Variable target condition) or no updating (Fixed target condition) of target identity, with updating activity estimated by condition comparison.

RESULTS

Normal updating activity using this paradigm involved bilateral activation of the dorsolateral prefrontal cortex (DLPFC) and inferior parietal lobe. The PTSD group lacked this activation in the left hemisphere and was significantly different from control subjects in this regard, but showed additional activation in the superior parietal lobe, bilaterally.

CONCLUSIONS

The pattern of parietal activation suggests a dependence on visuospatial coding for working memory representation of trauma-neutral, verbal information. Group differences in the relative involvement of the DLPFC indicate less dependence in PTSD on the executive role normally attributed to the left DLPFC for monitoring and manipulation of working memory content in posterior regions of the brain.

Recall of emotional states in posttraumatic stress disorder: an fMRI investigation

BACKGROUND

The goal of this study was to examine the neuronal circuitry underlying different emotional states (neutral, sad, anxious, and traumatic) in posttraumatic stress disorder (PTSD) in traumatized subjects versus traumatized subjects without PTSD.

METHODS

Traumatized subjects with (n = 10) and without (n = 10) PTSD were studied using the script-driven symptom provocation paradigm adapted to functional magnetic resonance imaging (fMRI) at a 4 Tesla field strength.

RESULTS

Compared to the trauma-exposed comparison group, PTSD subjects showed significantly less activation of the thalamus and the anterior cingulate gyrus (area 32) in all three emotional states (sad, anxious, and traumatic).

CONCLUSION

These findings suggest thalamic and anterior cingulate dysfunction in the recollection of traumatic as well as other negative events. Thalamic and anterior cingulate dysfunction may underlie emotion dysregulation often observed clinically in PTSD.

Psychological distress among evacuees of a volcanic eruption in Japan: A follow-up study

Psychological distress in 248 evacuees from a volcanic eruption was evaluated using a 30-item General Health Questionnaire (GHQ-30) at four time points after evacuation: 6 months, 12 months, 24 months and 44 months. The proportion of evacuees with psychological distress (defined as a GHQ score >/= 8) significantly decreased from 66.1% (6 months) to 45.6% (44 months). The GHQ mean score significantly improved from 12.6 to 8.9. Investigation of each factor on the GHQ showed progressive improvement over time in 'anxiety, tension and insomnia' and 'anergia and social dysfunction'. However, 'depression' began to improve only after 44 months and 'interpersonal dysfunction' started to worsen after 12 months. The dysfunction in interpersonal relationships continued at 44 months. Examination of the relation between GHQ mean scores and age group showed that recovery from psychological distress was more difficult in middle-aged and older evacuees than in younger evacuees.

Cerebral blood flow in depressed patients: a methodological comparison of statistical parametric mapping and region of interest analyses

Functional brain imaging has assumed a leading role in neuropsychiatric research. However, findings reported for mental disorders often vary. Whether this reflects diversity in pathophysiology or heterogeneity of imaging techniques and data-analytic procedures is still unknown. This study compares region of interest (ROI) and statistical parametric mapping (SPM) analyses of a Tc99m-HMPAO single photon emission computed tomography (SPECT) imaging study of 23 depressed and 21 control subjects. Reduced regional cerebral blood flow (rCBF) was demonstrated by both methods in the right parietal and occipital lobes, but additional regions were identified only on ROI analysis (left temporal) and only on SPM analysis (left parietal). To investigate the contribution of SPM spatial normalization to these discrepancies, further ROI analyses were performed, applying the original ROI templates to normalized images, and applying regions identified by SPM to the original images. This study demonstrated considerable overlap in findings of SPM and ROI analyses. Differences between these methods may be mostly related to subjective placement of ROIs in ROI analysis, and standardized warping inherent in normalization in SPM. Given the advantages and drawbacks of each procedure, the choice of methodology should be determined in accordance with the study design, and complementary use of both methods may be considered.

Neuropsychological function in female victims of intimate partner violence with and without posttraumatic stress disorder

BACKGROUND

Various aspects of neuropsychologic function have been reported to be abnormal in patients with posttraumatic stress disorder (PTSD); however, the majority of these data come from studies of seriously ill, treatment-seeking samples with substantial substance use comorbidity. Few studies have included similarly trauma-exposed subjects without PTSD, and fewer still have focused on women.

METHODS

Thirty-nine female victims of intimate partner violence (IPV; 22 without lifetime PTSD and 17 with current PTSD), and 22 nonvictimized comparison (NC) subjects were administered tests of attention, working memory, visuoconstruction, language ability, learning and memory, and executive functioning.

RESULTS

The IPV and NC subjects did not demonstrate statistically significant differences on most neuropsychologic tests, with the exception of those in the realm of working memory, visuoconstruction, and executive functioning. The IPV subjects, regardless of PTSD status, had poorer performance on tasks of speeded, sustained auditory attention and working memory (Paced Auditory Serial Addition Test) and response inhibition (Stroop). The IPV subjects with PTSD performed worse than NCs on a set-shifting task (Trail Making Test, Part B). No consistent relationships were noted between neuropsychologic functioning and severity of childhood abuse or domestic violence experiences.

CONCLUSIONS

Cognitive deficits in IPV subjects were confined to measures of working memory, visuoconstruction, and executive function; were subtle; and were not uniformly worse among those with current PTSD. This pattern, however, is consistent with frontal-subcortical dysfunction in traumatized women. The clinical significance of these findings deserves further study.

Post-traumatic stress disorder in women: current concepts and treatments

In the US, 13% of women develop post-traumatic stress disorder (PTSD) during their lifetime. An accurate diagnosis of PTSD requires screening for trauma and symptoms of PTSD. Current research in the neurobiologic and psychologic responses to traumatic stress supports the use of pharmacologic and psychosocial interventions. Selective serotonin reuptake inhibitors are the current first-line pharmacotherapy. Efficacious psychosocial interventions include exposure therapy and cognitive processing therapy.