Differential activity of subgenual cingulate and brainstem in panic disorder and PTSD.

Most functional neuroimaging studies of panic disorder (PD) have focused on the resting state, and have explored PD in relation to healthy controls rather than in relation to other anxiety disorders. Here, PD patients, posttraumatic stress disorder (PTSD) patients, and healthy control subjects were studied with functional magnetic resonance imaging utilizing an instructed fear conditioning paradigm incorporating both Threat and Safe conditions. Relative to PTSD and control subjects, PD patients demonstrated significantly less activation to the Threat condition and increased activity to the Safe condition in the subgenual cingulate, ventral striatum and extended amygdala, as well as in midbrain periaquaeductal grey, suggesting abnormal reactivity in this key region for fear expression.

Neuroimaging differences in spatial cognition between men and male-to-female transsexuals before and during hormone therapy.

Introduction: Neuropsychological abnormalities in transsexual patients have been reported in comparison with subjects without gender identity disorder (GID), suggesting differences in underlying neurobiological processes. However, these results have not consistently been confirmed. Furthermore, studies on cognitive effects of cross-sex hormone therapy also yield heterogeneous results.

Working-memory fMRI reveals cingulate hyperactivation in euthymic major depression.

While cognitive impairments are well documented for the acute episode of major depressive disorder (MDD), less is known about cognitive functioning in the euthymic state. For working memory, dysfunctional activation of lateral prefrontal and cingulate cortex has been reported in the acute episode. This study investigates working-memory function and its neurobiological correlate in euthymic MDD patients, particularly whether dysfunctional activation persists when depressive symptoms improve.

The functional anatomy of semantic retrieval is influenced by gender, menstrual cycle, and sex hormones.

This study examines the neurobiology of semantic retrieval and describes the influence of gender, menstrual cycle, and sex hormones on semantic networks. Healthy right-handed subjects (12 men, 12 women) were investigated with 3T-fMRI during synonym generation. Behavioral performance and sex hormone levels were assessed.

Influence of the catechol-O-methyltransferase val158met genotype on amygdala and prefrontal cortex emotional processing in panic disorder.

Panic disorder is an anxiety disorder with an estimated heritability of up to 48%. The functional val158met polymorphism in the catechol-O-methyltransferase (COMT) gene has been found to be associated with panic disorder and to influence limbic and prefrontal brain activation in response to unpleasant stimuli. In the present study, neuronal activation following emotional stimulation was used as an endophenotype and investigated for association with the COMT val158met polymorphism in panic disorder.

Human fear-related motor neurocircuitry.

Using functional magnetic resonance imaging and an experimental paradigm of instructed fear, we observed a striking pattern of decreased activity in primary motor cortex with increased activity in dorsal basal ganglia during anticipation of aversive electrodermal stimulation in 42 healthy participants. We interpret this pattern of activity in motor neurocircuitry in response to cognitively-induced fear in relation to evolutionarily-conserved responses to threat that may be relevant to understanding normal and pathological fear in humans.

Functional anatomy of visuo-spatial working memory during mental rotation is influenced by sex, menstrual cycle, and sex steroid hormones.

Recent observations indicate that sex and level of steroid hormones may influence cortical networks associated with specific cognitive functions, in particular visuo-spatial abilities. The present study probed the influence of sex, menstrual cycle, and sex steroid hormones on 3D mental rotation and brain function using 3-T fMRI. Twelve healthy women and 12 men were investigated.

Cognitive coping style modulates neural responses to emotional faces in healthy humans: a 3-T FMRI study.

Repression designates coping strategies that aim to shield the organism from distressing stimuli by disregarding their aversive characteristics. In contrast, sensitization comprises coping strategies that are employed to reduce situational uncertainty such as analyzing the environment. Functional magnetic resonance imaging was used to study neural correlates of coping styles during the perception of threatening and nonthreatening socially relevant information.

The association between depressive mood and cognitive performance in an elderly general population - the MEMO Study.

The aim of this study was to analyse the influence of the severity of depressive symptoms on different domains of cognitive function in the elderly. In a population-based cross-sectional study, 385 participants aged 65-83 years were interviewed with the Center for Epidemiologic Studies Depression Scale (CES-D) and performed a standardized neuropsychological test assessing attention, memory, cognitive speed and motor function. Multivariate linear regression analyses revealed a significant effect of depressive symptoms on a single test (Stroop test 1) and two summary scores (memory and motor function).

Increased brainstem volume in panic disorder: a voxel-based morphometric study.

Neurocircuitry models of panic disorder have hypothesized that the panic attack itself stems from loci in the brainstem including the ascending reticular system and respiratory and cardiovascular control centers. Voxel-based morphometry with acobian modulation was used to examine gray matter volume changes in 10 panic disorder patients and 23 healthy controls. The panic disorder patients had a relatively increased gray matter volume in the midbrain and rostral pons of the brainstem.

Association of the functional -1019C/G 5-HT1A polymorphism with prefrontal cortex and amygdala activation measured with 3 T fMRI in panic disorder.

Serotonergic genes have been implicated in the pathogenesis of panic disorder and amygdala function in response to fearful stimuli. Regional brain activation on visual presentation of emotional facial stimuli was investigated in 20 patients with panic disorder by means of fMRI at 3 T. All patients were genotyped for the functional -1019C/G 5-HT1A and 5-HTTLPR polymorphisms.

Functional neuroanatomy of non-verbal semantic sound processing in humans.

Environmental sounds convey specific meanings and the neural circuitry for their recognition may have preceded language. To dissociate semantic mnemonic from sensory perceptual processing of non-verbal sound stimuli we systematically altered the inherent semantic properties of non-verbal sounds from natural and man-made sources while keeping their acoustic characteristics closely matched. We hypothesized that acoustic analysis of complex non-verbal sounds would be right lateralized in auditory cortex regardless of meaning content and that left hemisphere regions would be engaged when meaningful concept could be extracted.

Processing of environmental sounds in schizophrenic patients: disordered recognition and lack of semantic specificity.

The recognition of environmental sounds is an important feature of higher auditory processing and essential for everyday life. The present study aimed to investigate the potential impairment of this mental function in schizophrenia. This work on immediate sound recognition is complementary to recent studies on auditory linguistic processing.

Physiological mapping of human auditory cortices with a silent event-related fMRI technique.

Cortical field boundaries of sensory areas can be physiologically defined. The delineation of the human auditory cortical architecture remains incomplete. Here we used systematic variation of pitch and duration of sinusoidal tones to define auditory cortical fields along Heschl's gyrus with a silent, event-related fMRI scanning technique that allowed us to determine spatially small shifts of neuronal responses.

Representational cortex in musicians. Plastic alterations in response to musical practice.

The lifelong ability to adapt to environmental needs is based on the capacity of the central nervous system for plastic alterations. In a series of neurophysiological experiments, we studied the impact of music and musical training in musicians on the specific functional organization in auditory and somatosensory representational cortex. In one such study, subjects listened to music from which one specific spectral frequency was removed.

Functional neuroimaging of human central auditory processing in normal subjects and patients with neurological and neuropsychiatric disorders.

Auditory sensory processing in the human cerebral cortex is disturbed in several neurological and neuropsychiatric disorders, ranging from devastating perceptual deficits in neuropsychological syndromes such as cortical deafness and auditory agnosia to the problem of involuntary hallucinatory perception in schizophrenia. With modern non-invasive functional imaging techniques (e.g.

Timbre-specific enhancement of auditory cortical representations in musicians.

Neural imaging studies have shown that the brains of skilled musicians respond differently to musical stimuli than do the brains of non-musicians, particularly for musicians who commenced practice at an early age. Whether brain attributes related to musical skill are attributable to musical practice or are hereditary traits that influence the decision to train musically is a subject of controversy, owing to its pedagogic implications. Here we report that auditory cortical representations measured neuromagnetically for tones of different timbre (violin and trumpet) are enhanced compared to sine tones in violinists and trumpeters, preferentially for timbres of the instrument of training.

A combined functional in vivo measure for primary and secondary auditory cortices.

Auditory evoked magnetic fields are reliable physiological in vivo markers of activity generated in auditory cortices. In recent years, several components of auditory evoked fields have been demonstrated with specific topographies within the auditory cortex in man. Their differential elicitation and analyses has rendered the discrimination of neural activities in primary vs.

The neural correlates of 'deaf-hearing' in man: conscious sensory awareness enabled by attentional modulation.

Attentional modulation of normal sensory processing has a two-fold impact on human brain activity: activation of a network of localized brain regions is associated with paying attention, and activation of specific sensory regions is enhanced relative to passive stimulation. The mechanisms underlying attentional modulation of perception in patients with lesions of sensory cortices are less well understood. Here we report a unique patient suffering from extensive bilateral destruction of the auditory cortices (including the primary auditory fields) who demonstrated conscious perception of the onset and offset of sounds only when selectively attending to the auditory modality.

A silent event-related functional MRI technique for brain activation studies without interference of scanner acoustic noise.

A new data acquisition method for silent, event-related functional MRI in which scanner acoustic noise does not interfere with brain activation is introduced and evaluated in an auditory tonotopic mapping experiment. This method takes into account the hemodynamic-response characteristics of the brain during activation, associated with both task performance and scanner noise. A data acquisition scheme was designed to collect task-induced brain activation signals without interference of scanner noise on stimulus delivery or on the measured response.

Short-term plasticity of the human auditory cortex.

Magnetoencephalographic measurements (MEG) were used to examine the effect on the human auditory cortex of removing specific frequencies from the acoustic environment. Subjects listened for 3 h on three consecutive days to music "notched" by removal of a narrow frequency band centered on 1 kHz. Immediately after listening to the notched music, the neural representation for a 1-kHz test stimulus centered on the notch was found to be significantly diminished compared to the neural representation for a 0.

Linguistic threat activates the human amygdala.

Studies in animals demonstrate a crucial role for the amygdala in emotional and social behavior, especially as related to fear and aggression. Whereas lesion and functional-imaging studies in humans indicate the amygdala's participation in assessing the significance of nonverbal as well as paralinguistic cues, direct evidence for its role in the emotional processing of linguistic cues is lacking. In this study, we use a modified Stroop task along with a high-sensitivity neuroimaging technique to target the neural substrate engaged specifically when processing linguistic threat.

Increased auditory cortical representation in musicians.

Acoustic stimuli are processed throughout the auditory projection pathway, including the neocortex, by neurons that are aggregated into 'tonotopic' maps according to their specific frequency tunings. Research on animals has shown that tonotopic representations are not statically fixed in the adult organism but can reorganize after damage to the cochlea or after training the intact subject to discriminate between auditory stimuli. Here we used functional magnetic source imaging (single dipole model) to measure cortical representations in highly skilled musicians.

Secondary hyperkalaemic paralysis.

Besides the hereditary hyperkalaemic paralysis, a secondary form exists which often mimicks Guillain-Barre syndrome. A 62 year old patient is reported on who developed severe hyperkalaemic paralysis on the basis of mild renal failure and additive spironolactone intake. Neurophysiological examinations disclosed normal muscle fibre activity but delayed nerve conduction velocities indicating that the mechanism underlying secondary hyperkalaemic paralysis is different from channelopathies.