共查询到20条相似文献,搜索用时 15 毫秒
1.
Laura C. Erickson Elizabeth Heeg Josef P. Rauschecker Peter E. Turkeltaub 《Human brain mapping》2014,35(11):5587-5605
The brain improves speech processing through the integration of audiovisual (AV) signals. Situations involving AV speech integration may be crudely dichotomized into those where auditory and visual inputs contain (1) equivalent, complementary signals (validating AV speech) or (2) inconsistent, different signals (conflicting AV speech). This simple framework may allow the systematic examination of broad commonalities and differences between AV neural processes engaged by various experimental paradigms frequently used to study AV speech integration. We conducted an activation likelihood estimation metaanalysis of 22 functional imaging studies comprising 33 experiments, 311 subjects, and 347 foci examining “conflicting” versus “validating” AV speech. Experimental paradigms included content congruency, timing synchrony, and perceptual measures, such as the McGurk effect or synchrony judgments, across AV speech stimulus types (sublexical to sentence). Colocalization of conflicting AV speech experiments revealed consistency across at least two contrast types (e.g., synchrony and congruency) in a network of dorsal stream regions in the frontal, parietal, and temporal lobes. There was consistency across all contrast types (synchrony, congruency, and percept) in the bilateral posterior superior/middle temporal cortex. Although fewer studies were available, validating AV speech experiments were localized to other regions, such as ventral stream visual areas in the occipital and inferior temporal cortex. These results suggest that while equivalent, complementary AV speech signals may evoke activity in regions related to the corroboration of sensory input, conflicting AV speech signals recruit widespread dorsal stream areas likely involved in the resolution of conflicting sensory signals. Hum Brain Mapp 35:5587–5605, 2014. © 2014 Wiley Periodicals, Inc . 相似文献
2.
Kaat Alaerts Daniel G. Woolley Jean Steyaert Adriana Di Martino Stephan P. Swinnen Nicole Wenderoth 《Social cognitive and affective neuroscience》2014,9(10):1589-1600
Neurodevelopmental disconnections have been assumed to cause behavioral alterations in autism spectrum disorders (ASDs). Here, we combined measurements of intrinsic functional connectivity (iFC) from resting-state functional magnetic resonance imaging (fMRI) with task-based fMRI to explore whether altered activity and/or iFC of the right posterior superior temporal sulcus (pSTS) mediates deficits in emotion recognition in ASD. Fifteen adults with ASD and 15 matched-controls underwent resting-state and task-based fMRI, during which participants discriminated emotional states from point light displays (PLDs). Intrinsic FC of the right pSTS was further examined using 584 (278 ASD/306 controls) resting-state data of the Autism Brain Imaging Data Exchange (ABIDE). Participants with ASD were less accurate than controls in recognizing emotional states from PLDs. Analyses revealed pronounced ASD-related reductions both in task-based activity and resting-state iFC of the right pSTS with fronto-parietal areas typically encompassing the action observation network (AON). Notably, pSTS-hypo-activity was related to pSTS-hypo-connectivity, and both measures were predictive of emotion recognition performance with each measure explaining a unique part of the variance. Analyses with the large independent ABIDE dataset replicated reductions in pSTS-iFC to fronto-parietal regions. These findings provide novel evidence that pSTS hypo-activity and hypo-connectivity with the fronto-parietal AON are linked to the social deficits characteristic of ASD. 相似文献
3.
Neural initialization of audiovisual integration in prereaders at varying risk for developmental dyslexia 下载免费PDF全文
Iliana I. Karipidis Georgette Pleisch Martina Röthlisberger Christoph Hofstetter Dario Dornbierer Philipp Stämpfli Silvia Brem 《Human brain mapping》2017,38(2):1038-1055
Learning letter‐speech sound correspondences is a major step in reading acquisition and is severely impaired in children with dyslexia. Up to now, it remains largely unknown how quickly neural networks adopt specific functions during audiovisual integration of linguistic information when prereading children learn letter‐speech sound correspondences. Here, we simulated the process of learning letter‐speech sound correspondences in 20 prereading children (6.13–7.17 years) at varying risk for dyslexia by training artificial letter‐speech sound correspondences within a single experimental session. Subsequently, we acquired simultaneously event‐related potentials (ERP) and functional magnetic resonance imaging (fMRI) scans during implicit audiovisual presentation of trained and untrained pairs. Audiovisual integration of trained pairs correlated with individual learning rates in right superior temporal, left inferior temporal, and bilateral parietal areas and with phonological awareness in left temporal areas. In correspondence, a differential left‐lateralized parietooccipitotemporal ERP at 400 ms for trained pairs correlated with learning achievement and familial risk. Finally, a late (650 ms) posterior negativity indicating audiovisual congruency of trained pairs was associated with increased fMRI activation in the left occipital cortex. Taken together, a short (<30 min) letter‐speech sound training initializes audiovisual integration in neural systems that are responsible for processing linguistic information in proficient readers. To conclude, the ability to learn grapheme‐phoneme correspondences, the familial history of reading disability, and phonological awareness of prereading children account for the degree of audiovisual integration in a distributed brain network. Such findings on emerging linguistic audiovisual integration could allow for distinguishing between children with typical and atypical reading development. Hum Brain Mapp 38:1038–1055, 2017. © 2016 Wiley Periodicals, Inc. 相似文献
4.
Wataru Sato Takanori Kochiyama Shota Uono Reiko Sawada Yasutaka Kubota Sayaka Yoshimura Motomi Toichi 《Human brain mapping》2019,40(13):3753-3768
Dynamic facial expressions of emotions constitute natural and powerful means of social communication in daily life. A number of previous neuroimaging studies have explored the neural mechanisms underlying the processing of dynamic facial expressions, and indicated the activation of certain social brain regions (e.g., the amygdala) during such tasks. However, the activated brain regions were inconsistent across studies, and their laterality was rarely evaluated. To investigate these issues, we measured brain activity using functional magnetic resonance imaging in a relatively large sample (n = 51) during the observation of dynamic facial expressions of anger and happiness and their corresponding dynamic mosaic images. The observation of dynamic facial expressions, compared with dynamic mosaics, elicited stronger activity in the bilateral posterior cortices, including the inferior occipital gyri, fusiform gyri, and superior temporal sulci. The dynamic facial expressions also activated bilateral limbic regions, including the amygdalae and ventromedial prefrontal cortices, more strongly versus mosaics. In the same manner, activation was found in the right inferior frontal gyrus (IFG) and left cerebellum. Laterality analyses comparing original and flipped images revealed right hemispheric dominance in the superior temporal sulcus and IFG and left hemispheric dominance in the cerebellum. These results indicated that the neural mechanisms underlying processing of dynamic facial expressions include widespread social brain regions associated with perceptual, emotional, and motor functions, and include a clearly lateralized (right cortical and left cerebellar) network like that involved in language processing. 相似文献
5.
Begliomini C Wall MB Smith AT Castiello U 《The European journal of neuroscience》2007,25(4):1245-1252
Effective grasping involves the remarkable ability to implement multiple grasp configurations such as precision grip (PG; opposition between the index finger and thumb) and whole-hand grasp (WHG), depending on the properties of the object grasped (e.g. size, shape and weight). In the monkey brain, different groups of cells in the anterior-lateral bank of the intraparietal sulcus (area AIP) are differentially active for various hand configurations during grasping of differently shaped objects. Visually guided grasping studies in humans suggest the anterior intraparietal sulcus (aIPS) as the homologue of macaque area AIP, but leave unresolved the question of whether activity in human aIPS reflects the relationship between object size and grasp configuration, as in macaques. To address this issue, a human fMRI study was conducted in which objects were grasped with the right hand while object size was varied. The results indicated that the left aIPS was active when the subjects naturally adopted a PG to grasp the small object but showed a much weaker response when subjects naturally adopted a WHG to grasp the large object. The primary motor cortex and somatosensory cortices were active for both PG and WHG. Our results suggest that, in humans, the aIPS is centrally involved in determining the type of grasp. 相似文献
6.
Krumbholz K Schönwiesner M Rübsamen R Zilles K Fink GR von Cramon DY 《The European journal of neuroscience》2005,21(1):230-238
Horizontal sound localization relies on the extraction of binaural acoustic cues by integration of the signals from the two ears at the level of the brainstem. The present experiment was aimed at detecting the sites of binaural integration in the human brainstem using functional magnetic resonance imaging and a binaural difference paradigm, in which the responses to binaural sounds were compared with the sum of the responses to the corresponding monaural sounds. The experiment also included a moving sound condition, which was contrasted against a spectrally and energetically matched stationary sound condition to assess which of the structures that are involved in general binaural processing are specifically specialized in motion processing. The binaural difference contrast revealed a substantial binaural response suppression in the inferior colliculus in the midbrain, the medial geniculate body in the thalamus and the primary auditory cortex. The effect appears to reflect an actual reduction of the underlying activity, probably brought about by binaural inhibition or refractoriness at the level of the superior olivary complex. Whereas all structures up to and including the primary auditory cortex were activated as strongly by the stationary as by the moving sounds, non-primary auditory fields in the planum temporale responded selectively to the moving sounds. These results suggest a hierarchical organization of auditory spatial processing in which the general analysis of binaural information begins as early as the brainstem, while the representation of dynamic binaural cues relies on non-primary auditory fields in the planum temporale. 相似文献
7.
Luis Morís Fernández Emiliano Macaluso Salvador Soto‐Faraco 《Human brain mapping》2017,38(11):5691-5705
There are two main behavioral expressions of multisensory integration (MSI) in speech; the perceptual enhancement produced by the sight of the congruent lip movements of the speaker, and the illusory sound perceived when a speech syllable is dubbed with incongruent lip movements, in the McGurk effect. These two models have been used very often to study MSI. Here, we contend that, unlike congruent audiovisually (AV) speech, the McGurk effect involves brain areas related to conflict detection and resolution. To test this hypothesis, we used fMRI to measure blood oxygen level dependent responses to AV speech syllables. We analyzed brain activity as a function of the nature of the stimuli—McGurk or non‐McGurk—and the perceptual outcome regarding MSI—integrated or not integrated response—in a 2 × 2 factorial design. The results showed that, regardless of perceptual outcome, AV mismatch activated general‐purpose conflict areas (e.g., anterior cingulate cortex) as well as specific AV speech conflict areas (e.g., inferior frontal gyrus), compared with AV matching stimuli. Moreover, these conflict areas showed stronger activation on trials where the McGurk illusion was perceived compared with non‐illusory trials, despite the stimuli where physically identical. We conclude that the AV incongruence in McGurk stimuli triggers the activation of conflict processing areas and that the process of resolving the cross‐modal conflict is critical for the McGurk illusion to arise. Hum Brain Mapp 38:5691–5705, 2017. © 2017 Wiley Periodicals, Inc. 相似文献
8.
Voice perception: Sex, pitch, and the right hemisphere 总被引:3,自引:0,他引:3
The present functional magnetic resonance imaging (fMRI) study examined the neurophysiological processing of voice information. The impact of the major acoustic parameters as well as the role of the listener's and the speaker's gender were investigated. Male and female, natural, and manipulated voices were presented to 16 young adults who were asked to judge the naturalness of each voice. The hemodynamic responses were acquired by a 3T Bruker scanner utilizing an event-related design. The activation was generally stronger in response to female voices as well as to manipulated voice signals, and there was no interaction with the listener's gender. Most importantly, the results suggest a functional segregation of the right superior temporal cortex for the processing of different voice parameters, whereby (1) voice pitch is processed in regions close and anterior to Heschl's Gyrus, (2) voice spectral information is processed in posterior parts of the superior temporal gyrus (STG) and areas surrounding the planum parietale (PP) bilaterally, and (3) information about prototypicality is predominately processed in anterior parts of the right STG. Generally, by identifying distinct functional regions in the right STG, our study supports the notion of a fundamental role of the right hemisphere in spoken language comprehension. 相似文献
9.
Yanlin Wang Ping Jiang Shi Tang Lu Lu Xuan Bu Lianqing Zhang Yingxue Gao Hailong Li Xinyu Hu Song Wang Zhiyun Jia Neil Roberts Xiaoqi Huang Qiyong Gong 《Social cognitive and affective neuroscience》2021,16(5):492
Anxiety and depressive symptoms may predispose individuals to sleep disturbance. Understanding how these emotional symptoms affect sleep quality, especially the underlying neural basis, could support the development of effective treatment. The aims of the present study were therefore to investigate potential changes in brain morphometry associated with poor sleep quality and whether this structure played a mediating role between the emotional symptoms and sleep quality. One hundred and forty-one healthy adults (69 women, mean age = 26.06 years, SD = 6.36 years) were recruited. A structural magnetic resonance imaging investigation was performed, and self-reported measures of anxiety, depressive symptoms and sleep quality were obtained for each participant. Whole-brain regression analysis revealed that worse sleep quality was associated with thinner cortex in left superior temporal sulcus (STS). Furthermore, the thickness of left STS mediated the association between the emotional symptoms and sleep quality. A subsequent commonality analysis showed that physiological component of the depressive symptoms had the greatest influence on sleep quality. In conclusion, thinner cortex in left STS may represent a neural substrate for the association between anxiety and depressive symptoms and poor sleep quality and may thus serve as a potential target for neuromodulatory treatment of sleep problems. 相似文献
10.
Wataru Sato Takanori Kochiyama Shota Uono Sakiko Yoshikawa 《Social cognitive and affective neuroscience》2008,3(3):224-232
The human superior temporal sulcus (STS) has been suggested to be involved in gaze processing, but temporal data regarding this issue are lacking. We investigated this topic by combining fMRI and MEG in four normal subjects. Photographs of faces with either averted or straight eye gazes were presented and subjects passively viewed the stimuli. First, we analyzed the brain areas involved using fMRI. A group analysis revealed activation of the STS for averted compared to straight gazes, which was confirmed in all subjects. We then measured brain activity using MEG, and conducted a 3D spatial filter analysis. The STS showed higher activity in response to averted versus straight gazes during the 150–200 ms period, peaking at around 170 ms, after stimulus onset. In contrast, the fusiform gyrus, which was detected by the main effect of stimulus presentations in fMRI analysis, exhibited comparable activity across straight and averted gazes at about 170 ms. These results indicate involvement of the human STS in rapid processing of the eye gaze of another individual. 相似文献
11.
12.
The postcentral sulcal complex and the transverse postcentral sulcus and their relation to sensorimotor functional organization 下载免费PDF全文
Veronika Zlatkina Céline Amiez Michael Petrides 《The European journal of neuroscience》2016,43(10):1268-1283
It has been demonstrated that the postcentral sulcus, which forms the posterior boundary of the sensorimotor region, is a complex of distinct sulcal segments. Although the general somatotopic arrangement in the human sensorimotor cortex is relatively well known, we do not know whether the different segments of the postcentral sulcus relate in a systematic way to the sensorimotor functional representations. Participants were scanned with functional magnetic resonance imaging while they made movements of different body parts and the location of functional activity was examined on a subject‐by‐subject basis with respect to the morphological features of the postcentral sulcus. The findings demonstrate that the postcentral sulcus of each subject may be divided into five segments and there is a tight relationship between sensorimotor representations of different body parts and specific segments of the postcentral sulcus. The results also addressed the issue of the transverse postcentral sulcus, a short sulcus that is present within the ventral part of the postcentral gyrus in some brains. It was shown that, when present, this sulcus is functionally related to the oral (mouth and tongue) sensorimotor representation. When this sulcus is not present, the inferior postcentral sulcus which is also related to the oral representation is longer. Thus, the sulcal morphology provides an improved framework for functional assignments in individual subjects. 相似文献
13.
《Brain stimulation》2020,13(4):1008-1013
BackgroundNeuroimaging studies suggest that facial expression recognition is processed in the bilateral posterior superior temporal sulcus (pSTS). Our recent repetitive transcranial magnetic stimulation (rTMS) study demonstrates that the bilateral pSTS is causally involved in expression recognition, although involvement of the right pSTS is greater than involvement of the left pSTS.Objective/Hypothesis: In this study, we used a dual-site TMS to investigate whether the left pSTS is functionally connected to the right pSTS during expression recognition. We predicted that if this connection exists, simultaneous TMS disruption of the bilateral pSTS would impair expression recognition to a greater extent than unilateral stimulation of the right pSTS alone.MethodsParticipants attended two TMS sessions. In Session 1, participants performed an expression recognition task while rTMS was delivered to the face-sensitive right pSTS (experimental site), object-sensitive right lateral occipital complex (control site) or no rTMS was delivered (behavioural control). In Session 2, the same experimental design was used, except that continuous theta-burst stimulation (cTBS) was delivered to the left pSTS immediately before behavioural testing commenced. Session order was counter-balanced across participants.ResultsIn Session 1, rTMS to the rpSTS impaired performance accuracy compared to the control conditions. Crucially in Session 2, the size of this impairment effect doubled after cTBS was delivered to the left pSTS.ConclusionsOur results provide evidence for a causal functional connection between the left and right pSTS during expression recognition. In addition, this study further demonstrates the utility of the dual-site TMS for investigating causal functional links between brain regions. 相似文献
14.
Sequential evolution of cortical activity and effective connectivity of swallowing using fMRI 下载免费PDF全文
Paul Glad Mihai Mareile Otto Thomas Platz Simon B. Eickhoff and Martin Lotze 《Human brain mapping》2014,35(12):5962-5973
Swallowing consists of a hierarchical sequence of primary motor and somatosensory processes. The temporal interplay of different phases is complex and clinical disturbances frequent. Of interest was the temporal interaction of the swallowing network. Time resolution optimized functional magnetic resonance imaging was used to describe the temporal sequence of representation sites of swallowing and their functional connectivity. Sixteen young healthy volunteers were investigated who swallowed 2 ml of water 20 times per run with a repetition time for functional imaging of 514 ms. After applying the general linear model approach to identify activation magnitude in preselected regions of interest repeated measures analysis of variance (rmANOVA) was used to detect relevant effects on lateralization, time, and onset. Furthermore, dynamic causal modeling (DCM) was applied to uncover where the input enters the model and the way in which the cortical regions are connected. The temporal analysis revealed a successive activation starting at the premotor cortex, supplementary motor area (SMA), and bilateral thalamus, followed by the primary sensorimotor cortex, the posterior insula, and cerebellum and culminating with activation in the pons shortly before subsiding. The rmANOVA revealed that activation was lateralized initially to the left hemisphere and gradually moved to the right hemisphere over time. The group random effects DCM analysis resulted in a most likely model that consisted of inputs to SMA and M1S1, bidirectionally connected, and a one‐way connection from M1S1 to the posterior insula. Hum Brain Mapp 35:5962–5973, 2014. © 2014 Wiley Periodicals, Inc . 相似文献
15.
Massimo Filippi 《European journal of neurology》2001,8(4):291-297
In patients with multiple sclerosis (MS), conventional magnetic resonance imaging (MRI) has markedly improved our ability to detect the macroscopic abnormalities of the brain and spinal cord. New quantitative magnetic resonance (MR) approaches with increased sensitivity to subtle normal-appearing white matter (NAWM) and grey matter changes and increased specificity to the heterogeneous pathological substrates of MS may give information complementary to conventional MRI. Magnetization transfer imaging (MTI) and diffusion-weighted imaging (DWI) have the potential to provide important information on the structural changes occurring within and outside T2-visible lesions. Magnetic resonance spectroscopy (MRS) adds information on the biochemical nature of such changes. Functional MRI might quantify the efficiency of brain plasticity in response to MS injury and improve our understanding of the link between structural damage and clinical manifestations. The present review summarizes how the application of these MR techniques to the study of MS is dramatically changing our understanding of how MS causes irreversible neurological deficits. 相似文献
16.
A functional magnetic resonance imaging study of cognitive control and neurosensory deficits in mild traumatic brain injury 下载免费PDF全文
Andrew R. Mayer Faith M. Hanlon Andrew B. Dodd Josef M. Ling Stefan D. Klimaj Timothy B. Meier 《Human brain mapping》2015,36(11):4394-4406
Mild traumatic brain injury patients (mTBI) frequently report symptoms of increased distractability and sensory disturbances during mutisensory stimulation. These common post‐concussive symptoms could putatively result from dysfunction within the cognitive control network (CCN; top‐down) or from unisensory cortex (bottom‐up) itself. Functional magnetic resonance imaging (fMRI) and high‐resolution structural data were therefore prospectively collected during a multisensory (audio‐visual) cognitive control task from 46 mTBI patients within 3 weeks of injury and 46 matched healthy controls (HC), with a subset of participants returning at 4 months. Multisensory stimuli were presented at two frequencies to manipulate cognitive and perceptual load. Patients self‐reported more cognitive, emotional, somatic, vestibular and visual symptoms relative to HC, which improved, but did not entirely resolve, over the 4 month follow‐up period. There were no group differences in behavior or functional activation during cognitive control (incongruent – congruent trials). In contrast, patients exhibited abnormal activation within different regions of visual cortex that depended on whether attention was focused on auditory or visual information streams. Patients also exhibited increased activation within bilateral inferior parietal lobules during higher cognitive/perceptual loads, suggesting a compensatory mechanism to achieve similar levels of behavioral performance. Functional abnormalities within the visual cortex and inferior parietal lobules were only partially resolved at 4 months post‐injury, suggesting that neural abnormalities may take longer to resolve than behavioral measures used in most clinical settings. In summary, current results indicate that abnormalities within unisensory cortex (particularly visual areas) following mTBI, which likely contribute to deficits commonly reported during multisensory stimulation. Hum Brain Mapp 36:4394–4406, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
17.
Numerical and spatial magnitude processing have long been intimately associated, leading to the suggestion that they share a common system of magnitude representation. Although separate investigations on the cerebral areas involved in numerosity and spatial estimation point toward the parietal cortex, the precise anatomical overlap, if any, has not yet been directly established. Here, functional magnetic resonance imaging was used to localize the cerebral network involved in processing both numerosity and length. Blood oxygenation level‐dependent signal changes were measured while healthy volunteers were making numerosity comparisons on linear arrays of dots, and length comparisons on discrete linear arrays of dots and continuous rectangles. The results show the bilateral involvement of parietal regions around the intraparietal sulci in explicit and implicit processing of numerosity, and a right lateralized occipitoparietal network activation in length processing; numerosity and length processing both activate the right IPS and the precentral gyrus. By excluding the mandatory intrinsic spatial processing of arrays, we demonstrate that the left IPS is involved in numerosity processing only, whereas the right IPS underlies a common processing mechanism or representation of spatial and numerical magnitude. Hum Brain Mapp 2009. © 2009 Wiley‐Liss, Inc. 相似文献
18.
By means of fMRI measurements, the present study identifies brain regions in left and right peri-sylvian areas that subserve grammatical or prosodic processing. Normal volunteers heard 1) normal sentences; 2) so-called syntactic sentences comprising syntactic, but no lexical-semantic information; and 3) manipulated speech signals comprising only prosodic information, i.e., speech melody. For all conditions, significant blood oxygenation signals were recorded from the supratemporal plane bilaterally. Left hemisphere areas that surround Heschl gyrus responded more strongly during the two sentence conditions than to speech melody. This finding suggests that the anterior and posterior portions of the superior temporal region (STR) support lexical-semantic and syntactic aspects of sentence processing. In contrast, the right superior temporal region, in especially the planum temporale, responded more strongly to speech melody. Significant brain activation in the fronto-opercular cortices was observed when participants heard pseudo sentences and was strongest during the speech melody condition. In contrast, the fronto-opercular area is not prominently involved in listening to normal sentences. Thus, the functional activation in fronto-opercular regions increases as the grammatical information available in the sentence decreases. Generally, brain responses to speech melody were stronger in right than left hemisphere sites, suggesting a particular role of right cortical areas in the processing of slow prosodic modulations. 相似文献
19.
Numerosity and duration processing have been modeled by a functional mechanism taking the form of an accumulator working under two different operative modes. Separate investigations of their cerebral substrates have revealed partly similar patterns of activation, mainly in parietal and frontal areas. However, the precise cerebral implementation of the accumulator model within these areas has not yet been directly assessed. In this study, we asked participants to categorize the numerosity of flashed dot sequences or the duration of single dot displays, and we used functional magnetic resonance imaging (fMRI) to examine the common neural correlates of these processes. The results reveal a large right-lateralized fronto-parietal network, including the intraparietal sulcus (IPS) and areas in the precentral, middle and superior frontal gyri, which is activated by both numerosity and duration processing. Complementary psychophysiological interaction (PPI) analyses show a functional connectivity between the right IPS and the frontal areas in both tasks, whereas the right IPS was functionally connected to the left IPS and the right precentral area in the numerosity categorization task only. We propose that the right IPS underlies a common magnitude processing system for both numerosity and duration, possibly corresponding to the encoding and accumulation stages of the accumulator model, whereas the frontal areas are involved in subsequent working-memory storage and decision-making processes. 相似文献
20.
The detection of coherent motion embedded in noise has been widely used as a measure of global visual motion processing. Animal studies have demonstrated that this performance is closely linked to the responses of direction-sensitive neurons in the macaque middle temporal (MT) and medial superior temporal (MST) areas. Despite the strong similarities between the visual cortex of human and that of non-human primates, the human middle temporal complex (area MT+), located in the posterior part of the inferior temporal sulcus and presumably comprising both area MT and area MST, has not consistently been found to share the functional hallmark of MT and MST neurons, i.e. their preference for coherent rather than incoherent visual motion. In order to search for such preferences in human area MT+, blood oxygen level-dependent responses to random dot kinematograms presented in the right visual hemifield were studied here as a function of stimulus size and dot density. The stimulus extensions were varied in such a way as to cover an area either equaling, exceeding or falling below the mean receptive field size of macaque area MT. Unlike the posterior part of human area MT+, the anterior part and its right-hemisphere homolog showed significantly stronger responses to coherent than to incoherent motion. These differences were only present for large stimuli that presumably exceeded the receptive field size of neurons in area MT. Our results suggest that functional magnetic resonance imaging may reveal stronger responses to coherent visual motion in human area MST, provided that the stimulus allows for sufficient summation within the receptive fields. In contrast, functional magnetic resonance imaging may fail to reveal the same dependency for human area MT. 相似文献