Aggression modulates neural correlates of hostile intention attribution to laughter in children.

The tendency to interpret nonverbal social signals as hostile in intention is associated with aggressive responding, poor social functioning and mental illness, and can already be observed in childhood. To investigate the neural correlates of such hostile attributions of social intention, we performed a functional magnetic imaging study in 10-18 year old children and adolescents. Fifty healthy participants rated videos of laughter, which they were told to imagine as being directed towards them, as friendly versus hostile in social intention. Hostile intention ratings were associated with neural response in the right temporal voice area (TVA). Moreover, self-reported trait physical aggression modulated this relationship in both the right TVA and bilateral lingual gyrus, with stronger associations between hostile intention ratings and neural activation in children with higher trait physical aggression scores. Functional connectivity results showed decreased connectivity between the right TVA and left dorsolateral prefrontal cortex with increasing trait physical aggression for making hostile social intention attributions. We conclude that children's social intention attributions are more strongly related to activation of early face and voice-processing regions with increasing trait physical aggression.

Functional connectivity changes following interpersonal reactivity.

Attachment experiences substantially influence emotional and cognitive development. Narratives comprising attachment-dependent content were proposed to modulate activation of cognitive-emotional schemata in listeners. We studied the effects after listening to prototypical attachment narratives on wellbeing and countertransference-reactions in 149 healthy participants. Neural correlates of these cognitive-emotional schema activations were investigated in a 7 Tesla rest-task-rest fMRI-study (23 healthy males) using functional connectivity (FC) analysis of the social approach network (seed regions: left and right Caudate Nucleus, CN). Reduced FC between left CN and bilateral dorsolateral prefrontal cortex (DLPFC) represented a general effect of prior auditory stimulation. After presentation of the insecure-dismissing narrative, FC between left CN and bilateral temporo-parietal junction, and right dorsal posterior Cingulum was reduced, compared to baseline. Post-narrative FC-patterns of insecure-dismissing and insecure-preoccupied narratives differed in strength between left CN and right DLPFC. Neural correlates of the moderating effect of individual attachment anxiety were represented in a reduced CN-DLPFC FC as a function of individual neediness-levels. These findings suggest specific neural processing of prolonged mood-changes and schema activation induced by attachment-specific speech patterns. Individual desire for interpersonal proximity was predicted by attachment anxiety and furthermore modulated FC of the social approach network in those exposed to such narratives.

Aggression differentially modulates neural correlates of social intention attribution to benevolent, tickling and taunting laughter: An fMRI study in children and adolescents.

Human laughter is a powerful means of communicating social intention, ranging from welcoming and friendly to hostile and ridiculing. To be communicated accurately, the recipient must correctly identify the laugher's underlying social intention. Regular misattribution of the social intention of others has been associated with maladaptive psychosocial development, in particular with aggressive behavior. We investigated the relationship between self-reported aggressive behavior and the neural correlates of social intention attributions to different audiovisual laughter types in 50 healthy children and adolescents (29 female, 10-18 years, M 15.5, SD 2.2) using functional magnetic resonance imaging. Trial-by-trial associations of neural response and behavioral attributions were distinctly modulated by aggression for benevolent versus taunting and tickling laughter. With increasing aggression, hostile misattributions of benevolent laughter were associated with decreased dorsolateral prefrontal and anterior insular cortex activation. In contrast, hostile attributions of taunting and tickling laughter were associated with increased superior frontal, superior temporal, medial prefrontal, supplementary motor, and anterior and mid-cingulate cortex activation. We argue that aggression may be associated with down-regulated emotional saliency of benevolent laughter, whereas up-regulated neural responses to taunting laughter may underlie a heightened sensitivity to hostility or acceptance of taunting behavior in more aggressive individuals.

Cerebral processing of linguistic and emotional prosody: fMRI studies.

During acoustic communication in humans, information about a speaker's emotional state is predominantly conveyed by modulation of the tone of voice (emotional or affective prosody). Based on lesion data, a right hemisphere superiority for cerebral processing of emotional prosody has been assumed. However, the available clinical studies do not yet provide a coherent picture with respect to interhemispheric lateralization effects of prosody recognition and intrahemispheric localization of the respective brain regions. To further delineate the cerebral network engaged in the perception of emotional tone, a series of experiments was carried out based upon functional magnetic resonance imaging (fMRI). The findings obtained from these investigations allow for the separation of three successive processing stages during recognition of emotional prosody: (1) extraction of suprasegmental acoustic information predominantly subserved by right-sided primary and higher order acoustic regions; (2) representation of meaningful suprasegmental acoustic sequences within posterior aspects of the right superior temporal sulcus; (3) explicit evaluation of emotional prosody at the level of the bilateral inferior frontal cortex. Moreover, implicit processing of affective intonation seems to be bound to subcortical regions mediating automatic induction of specific emotional reactions such as activation of the amygdala in response to fearful stimuli. As concerns lower level processing of the underlying suprasegmental acoustic cues, linguistic and emotional prosody seem to share the same right hemisphere neural resources. Explicit judgment of linguistic aspects of speech prosody, however, appears to be linked to left-sided language areas whereas bilateral orbitofrontal cortex has been found involved in explicit evaluation of emotional prosody. These differences in hemispheric lateralization effects might explain that specific impairments in nonverbal emotional communication subsequent to focal brain lesions are relatively rare clinical observations as compared to the more frequent aphasic disorders.

Early left periventricular brain lesions induce right hemispheric organization of speech.

Right-hemispheric organization of speech has been observed following early left-sided brain lesions involving the language cortex. The authors studied speech organization in hemiparetic patients with pre- and perinatally acquired lesions in the left periventricular white matter using fMRI, and found that right-hemisphere activation correlated with left facial motor tract involvement. This suggests that the impairment of speech motor output from the left hemisphere plays an important role in this alteration of language representation.

Dynamic pattern of brain activation during sequencing of word strings evaluated by fMRI.

An impaired ability to recite highly automated word strings (e.g., the names of the months of the year) in reverse order concomitant with preserved production of the conventional sequence has been considered a salient sign of frontal lobe dysfunction. Using functional magnetic resonance imaging (fMRI), the spatial and temporal pattern of brain activation during covert performance of these tasks was evaluated in healthy subjects. As compared to the response obtained during forward recitation, re-sequencing of the word string yielded additional activation of the bilateral middle and inferior frontal gyri, the posterior parietal cortex and the left anterior cingulate gyrus. The prefrontal responses are in accordance with the clinical findings referred to. However, the set of activated areas, as a whole, presumably reflects contribution of the various components of the working memory system to the sequencing of word strings. During successive periods of task administration, subjects showed a linear increase of production speed. Analysis of corresponding dynamic changes of regional hemodynamic responses revealed a significant increase at the level of the left inferior parietal cortex and a decrease within the mesial aspect of the left superior frontal gyrus. Presumably, the former finding reflects increasing demands on the phonological short-term memory store, due to faster updating of its content under increased word production rate. Decreasing activation within the superior frontal gyrus might indicate contribution of this area to the initiation of the cognitive processes subserving the sequencing of verbal items. These findings demonstrate the capability of fMRI as a powerful tool for the analysis of dynamic brain activation.

Opposite hemispheric lateralization effects during speaking and singing at motor cortex, insula and cerebellum.

Aside from spoken language, singing represents a second mode of acoustic (auditory-vocal) communication in humans. As a new aspect of brain lateralization, functional magnetic resonance imaging (fMRI) revealed two complementary cerebral networks subserving singing and speaking. Reproduction of a non-lyrical tune elicited activation predominantly in the right motor cortex, the right anterior insula, and the left cerebellum whereas the opposite response pattern emerged during a speech task. In contrast to the hemodynamic responses within motor cortex and cerebellum, activation of the intrasylvian cortex turned out to be bound to overt task performance. These findings corroborate the assumption that the left insula supports the coordination of speech articulation. Similarly, the right insula might mediate temporo-spatial control of vocal tract musculature during overt singing. Both speech and melody production require the integration of sound structure or tonal patterns, respectively, with a speaker's emotions and attitudes. Considering the widespread interconnections with premotor cortex and limbic structures, the insula is especially suited for this task.

Functional lateralization of speech production at primary motor cortex: a fMRI study.

To evaluate lateralization of speech production at the level of the Rolandic cortex, functional magnetic resonance imaging (1.5 Tesla, 27 parallel axial slices, EPI-technique) was performed during a speech task (continuous silent recitation of the names of the months of the year). As control conditions, non-speech tongue movements and silent singing of a well-known melody with the syllable 'la' as its carrier were considered. Tongue movements produced symmetrical activation at the lower primary motor cortex. During automatic speech a strong functional lateralization to the left hemisphere emerged within the same area. In contrast, singing yielded a predominant right-sided activation of the Rolandic region. Functional lateralization of speech production therefore seems to include the precentral gyrus as well as Broca's area.

Rate-dependent activation of a prefrontal-insular-cerebellar network during passive listening to trains of click stimuli: an fMRI study.

Eight volunteers underwent fMRI during passive listening to click trains. Using a parametric approach, rate-response profiles across the frequency band considered (2-6 Hz) were determined. Several cerebral structures outside the central-auditory pathways and target areas displayed distinct activation patterns each: rate-response profiles resembling high-pass (left side) or low-pass filtered (right side) signal series emerged at the level of the anterior insula, band-pass like characteristics (center frequency: 3-4 Hz) were observed within the left inferior frontal gyrus, and click train rates > 4 Hz yielded enhanced activation of the right cerebellar hemisphere. A variety of clinical and experimental data indicate that the left and right cerebral hemispheres act as high- and low-pass filters, respectively, on auditory input (double filtering by frequency theory). In light of the present fMRI data, the anterior insula contributes to the assumed double filtering by frequency functions. Furthermore, these intrasylvian areas seem to join up with the right cerebellum and the left inferior frontal gyrus to a network subserving parsing/timing functions within the auditory-verbal domain.

Sequential activation of supplementary motor area and primary motor cortex during self-paced finger movement in human evaluated by functional MRI.

The 'Bereitschaftspotential' attributed to activation of the supplementary motor area (SMA) precedes the 'motor potential' of the primary motor cortex (Ml) about 500-1000 ms during self-initiated movements. A measurement procedure is reported to evaluate the sequence of hemodynamic activation within both motor areas by functional magnetic resonance imaging (fMRI). The fMRI-data were averaged across multiple trials of single voluntary finger movements and analyzed with respect to the onset-time of signal increase. All participants showed a sequential hemodynamic response with SMA preceding M1 activation. The mean latency between hemodynamic activation of SMA and M1 amounted to 0.8 s. These findings suggest that the vascular response parallels the electrical events and that a sufficient temporal resolution can be achieved by fMRI to detect sequential hemodynamic activation of functionally connected cortical areas.

Does the cerebellum contribute to cognitive aspects of speech production? A functional magnetic resonance imaging (fMRI) study in humans.

Several positron emission tomography (PET) studies suggest a contribution of the lateral aspects of the right cerebellar hemisphere to higher-level (cognitive) aspects of speech production such as controlled verbal response selection. As an alternative, however, 'inner speech', giving rise to subliminal activity of orofacial and laryngeal muscles, might account for the observed activation effects. Eighteen subjects underwent functional magnetic resonance imaging (fMRI) during continuous silent recitation of the names of the months of the year ('automatic speech'). The right cerebellar hemisphere showed a significantly increased hemodynamic response concomitant with, among others, an asymmetric activation pattern towards the left side at the level of the motor strip. Since highly overlearned word strings, presumably, pose few demands on controlled response selection and since the projections of the right cerebellar hemisphere to the left precentral gyrus participate in motor control, the observed cerebellar activation, thus, seems to be related to the articulatory level of speech production rather than, as suggested by previous PET studies, to cognitive operations.

Ultrafast diffusion-sensitive MR imaging of brain on an open scanner at 0.2 T.

We describe new strategies for fast diffusion-sensitive MR imaging of ischemic brain or spinal cord lesions. The methods provide diagnostic image quality in less than 1 s per section and are used in conjunction with low-field-strength open MR scanners. Single-shot sequences combine diffusion-sensitive preparation with a modified fast spin-echo data acquisition. Results are presented from healthy volunteers and from two patients with recent and older ischemic brain lesions.

Improvement of the acquisition of a large amount of MR images on a conventional whole body system.

Modern whole body MR systems are equipped with echo-planar-imaging capability, which allows the measurement of a single slice in a fraction of a second or of thousands of images in few minutes. A considerable restriction to the acquisition of series containing large amounts of images in patient examinations is the time-consuming data handling time of the images at conventional systems, which includes the time to insert the images into the systems database. We propose the arrangement of several images on a new image with a large matrix size like a mosaic. The handling time depends mostly on the number of images without consideration of their matrix size. Therefore, image handling is strongly reduced by the use of such mosaic images.

Articulatory/phonetic sequencing at the level of the anterior perisylvian cortex: a functional magnetic resonance imaging (fMRI) study.

Damage to the anterior peri-intrasylvian cortex of the dominant hemisphere may give rise to a fairly consistent syndrome of articulatory deficits in the absence of relevant paresis of orofacial or laryngeal muscles (apraxia of speech, aphemia, or phonetic disintegration). The available clinical data are ambiguous with respect to the relevant lesion site, indicating either dysfunction of the premotor aspect of the lower precentral gyrus or the anterior insula in the depth of the Sylvian fissure. In order to further specify the functional anatomic substratum of this syndrome, functional magnetic resonance imaging (fMRI) was performed during reiteration of syllables differing in their demands on articulatory/phonetic sequencing (CV versus CCCV versus CVCVCV). Horizontal tongue movements and a polysyllabic lexical item served as control conditions. Repetition of the CV and CCCV monosyllables elicited a rather bilateral symmetric hemodynamic response at the level of the anterior and posterior bank of the central sulcus (primary sensorimotor cortex), whereas a more limited area of neural activity arose within this domain during production of lexical and nonlexical polysyllables, significantly or exclusively lateralized toward the left hemisphere. There is neurophysiological evidence that primary sensorimotor cortex mediates the "fractionation" of movements. Assuming that the polysyllables considered are organized as coarticulated higher-order units, the observed restricted and lateralized cortical activation pattern, most presumably, reflects a mode of "nonindividualized" motor control posing fewer demands on "movement fractionation." These findings may explain the clinical observation of disproportionately worse repetition of trisyllabic items as compared to monosyllables in apraxia of speech. The various test materials failed to elicit significant activation of the anterior insula. If at all, only horizontal tongue movements yielded a hemodynamic reaction extending beyond the sensorimotor cortex to premotor areas. Since limbic projections target the inferior dorsolateral frontal lobe, the enlarged region of activation during horizontal tongue movements might reflect increased attentional requirements of this task.

fMRI reveals two distinct cerebral networks subserving speech motor control.

BACKGROUND: There are few data on the cerebral organization of motor aspects of speech production and the pathomechanisms of dysarthric deficits subsequent to brain lesions and diseases. The authors used fMRI to further examine the neural basis of speech motor control. METHODS AND RESULTS: In eight healthy volunteers, fMRI was performed during syllable repetitions synchronized to click trains (2 to 6 Hz; vs a passive listening task). Bilateral hemodynamic responses emerged at the level of the mesiofrontal and sensorimotor cortex, putamen/pallidum, thalamus, and cerebellum (two distinct activation spots at either side). In contrast, dorsolateral premotor cortex and anterior insula showed left-sided activation. Calculation of rate/response functions revealed a negative linear relationship between repetition frequency and blood oxygen level-dependent (BOLD) signal change within the striatum, whereas both cerebellar hemispheres exhibited a step-wise increase of activation at approximately 3 Hz. Analysis of the temporal dynamics of the BOLD effect found the various cortical and subcortical brain regions engaged in speech motor control to be organized into two separate networks (medial and dorsolateral premotor cortex, anterior insula, and superior cerebellum vs sensorimotor cortex, basal ganglia, and inferior cerebellum). CONCLUSION: These data provide evidence for two levels of speech motor control bound, most presumably, to motor preparation and execution processes. They also help to explain clinical observations such as an unimpaired or even accelerated speaking rate in Parkinson disease and slowed speech tempo, which does not fall below a rate of 3 Hz, in cerebellar disorders.

Identification of emotional intonation evaluated by fMRI.

During acoustic communication among human beings, emotional information can be expressed both by the propositional content of verbal utterances and by the modulation of speech melody (affective prosody). It is well established that linguistic processing is bound predominantly to the left hemisphere of the brain. By contrast, the encoding of emotional intonation has been assumed to depend specifically upon right-sided cerebral structures. However, prior clinical and functional imaging studies yielded discrepant data with respect to interhemispheric lateralization and intrahemispheric localization of brain regions contributing to processing of affective prosody. In order to delineate the cerebral network engaged in the perception of emotional tone, functional magnetic resonance imaging (fMRI) was performed during recognition of prosodic expressions of five different basic emotions (happy, sad, angry, fearful, and disgusted) and during phonetic monitoring of the same stimuli. As compared to baseline at rest, both tasks yielded widespread bilateral hemodynamic responses within frontal, temporal, and parietal areas, the thalamus, and the cerebellum. A comparison of the respective activation maps, however, revealed comprehension of affective prosody to be bound to a distinct right-hemisphere pattern of activation, encompassing posterior superior temporal sulcus (Brodmann Area [BA] 22), dorsolateral (BA 44/45), and orbitobasal (BA 47) frontal areas. Activation within left-sided speech areas, in contrast, was observed during the phonetic task. These findings indicate that partially distinct cerebral networks subserve processing of phonetic and intonational information during speech perception.

[Neuroradiologic activation studies of cerebral organization of language capacities. A review of the literature]. / Neuroradiologische Aktivierungsstudien zur zerebralen Organisation sprachlicher Leistungen. Eine Literaturübersicht.

Models on the cerebral organisation of speech and language capacities are predominantly based on lesion studies. Neuroradiological activation methods using positron emission or magnetic resonance tomography provide a further means to investigate brain-behaviour relationships. The present paper reviews the available data obtained with functional imaging during speech and language tasks. The classical connectionist model suggests several distinct language centres within the perisylvian area of the dominant hemisphere. Especially the processing of complex verbal stimuli yields haemodynamic and metabolic reactions outside this area. At least partially, these extrasylvian foci might reflect paralinguistic functions such as motivational or attentional aspects of speech production, or the processing of emotions conveyed by verbal utterances. As far as linguistic capacities are concerned, functional imagery has yielded two results which extend the classical connectionist model of speech and language functions: (a) the medial part of the occipital lobe of the dominant hemisphere seems to comprise representations of visual word forms; (b) word generation yields activation of cerebellar structures. In contrast to the classical connectionist model, reading did not cause reactions of the angular region of the left hemisphere. Furthermore, phonological and semantic processing of verbal stimuli include the anterior perisylvian language zones. The interpretation of discrepancies between data derived from lesion studies and those obtained with functional imaging is still unsettled. First of all, rapid cognitive processes do not necessarily give rise to a detectable significant haemodynamic or metabolic response. Secondly, highly automatised language processes such as inner speech are difficult to control.

Differential contributions of motor cortex, basal ganglia, and cerebellum to speech motor control: effects of syllable repetition rate evaluated by fMRI.

In order to delineate the neuroanatomical correlates of speech motor control, functional magnetic resonance imaging was performed during silent repetitions of the syllable "ta" at three different rates (2.5, 4.0, and 5.5 Hz). Spatial extent and magnitude of hemodynamic responses at the level of the motor cortex showed a positive correlation to production frequencies. As concerns the basal ganglia, the lower rates (2.5 and 4.0 Hz) gave rise to higher magnitudes of activation within the left putamen as compared to the 5.5 Hz condition. In contrast, cerebellar responses were rather restricted to fast performance (4.0 and 5.5 Hz) and exhibited a shift in caudal direction during 5.5 as compared to 4.0 Hz. These findings corroborate the suggestion of a differential impact of various cortical and subcortical areas on speech motor control.

The Frontal Lobe Score: part II: evaluation of its clinical validity.

OBJECTIVE: To evaluate the ability of the Frontal Lobe Score (FLS) to differentiate patients with frontal lobe lesions from those with nonfrontal lesions and normal controls. DESIGN: In a prospective, blind setup, the sensitivity and specificity of the Frontal Lobe Score was compared with the Wisconsin Card Sorting Test (WCST) and the Stroop Test. PATIENTS: A sample of 108 subjects (26 patients with cerebral lesions confined to the frontal lobes, 28 patients with cerebral lesions without involvement of the frontal lobes, 31 patients with mixed frontal/nonfrontal lesions, 23 controls without cerebral lesions) was examined. MEASURES: Frontal Lobe Score, Wisconsin Card Sorting Test, Stroop Test. RESULTS: The Frontal Lobe Score detected pure frontal lesions with a sensitivity of 92.3%. It discriminated patients with frontal lesions from normal controls with a specificity of 100%; differentiation from patients with nonfrontal lesions was obtained with a specificity of 75.0%. For the WCST, sensitivity for detection of pure frontal lesions was 65.4%, while specificity was 60.9% compared with normal controls and 53.6% compared with nonfrontal lesions. The Stroop Test showed a sensitivity of 30.8%, a specificity compared with normal controls of 95.7% and compared with nonfrontal lesions of 92.9%. CONCLUSION: The Frontal Lobe Score has clinical usefulness for screening of effects of frontal lobe damage superior to that of the WCST and the Stroop Test.