Intermodal Selective Attention Research Articles

Cochlear Theta Activity Oscillates in Phase Opposition during Interaural Attention.

It is widely established that sensory perception is a rhythmic process as opposed to a continuous one. In the context of auditory perception, this effect is only established on a cortical and behavioral level. Yet, the unique architecture of the auditory sensory system allows its primary sensory cortex to modulate the processes of its sensory receptors at the cochlear level. Previously, we could demonstrate the existence of a genuine cochlear theta (∼6-Hz) rhythm that is modulated in amplitude by intermodal selective attention. As the study's paradigm was not suited to assess attentional effects on the oscillatory phase of cochlear activity, the question of whether attention can also affect the temporal organization of the cochlea's ongoing activity remained open. The present study utilizes an interaural attention paradigm to investigate ongoing otoacoustic activity during a stimulus-free cue-target interval and an omission period of the auditory target in humans. We were able to replicate the existence of the cochlear theta rhythm. Importantly, we found significant phase opposition between the two ears and attention conditions of anticipatory as well as cochlear oscillatory activity during target presentation. Yet, the amplitude was unaffected by interaural attention. These results are the first to demonstrate that intermodal and interaural attention deploy different aspects of excitation and inhibition at the first level of auditory processing. Whereas intermodal attention modulates the level of cochlear activity, interaural attention modulates the timing.

Cochlear activity in silent cue-target intervals shows a theta-rhythmic pattern and is correlated to attentional alpha and theta modulations

BackgroundA long-standing debate concerns where in the processing hierarchy of the central nervous system (CNS) selective attention takes effect. In the auditory system, cochlear processes can be influenced via direct and mediated (by the inferior colliculus) projections from the auditory cortex to the superior olivary complex (SOC). Studies illustrating attentional modulations of cochlear responses have so far been limited to sound-evoked responses. The aim of the present study is to investigate intermodal (audiovisual) selective attention in humans simultaneously at the cortical and cochlear level during a stimulus-free cue-target interval.ResultsWe found that cochlear activity in the silent cue-target intervals was modulated by a theta-rhythmic pattern (~ 6 Hz). While this pattern was present independently of attentional focus, cochlear theta activity was clearly enhanced when attending to the upcoming auditory input. On a cortical level, classical posterior alpha and beta power enhancements were found during auditory selective attention. Interestingly, participants with a stronger release of inhibition in auditory brain regions show a stronger attentional modulation of cochlear theta activity.ConclusionsThese results hint at a putative theta-rhythmic sampling of auditory input at the cochlear level. Furthermore, our results point to an interindividual variable engagement of efferent pathways in an attentional context that are linked to processes within and beyond processes in auditory cortical regions.

Differential attention-dependent adjustment of frequency, power and phase in primary sensory and frontoparietal areas

Continuously prioritizing behaviourally relevant information from the environment for improved stimulus processing is a crucial function of attention. In the current MEG study, we investigated how ongoing oscillatory activity of both sensory and non-sensory brain regions are differentially impacted by attentional focus. Low-frequency phase alignment of neural activity in primary sensory areas, with respect to attended/ignored features has been suggested to support top-down prioritization. However, phase adjustment in frontoparietal regions has not been widely studied, despite general implication of these in top-down selection of information. To investigate this, we let participants perform an established intermodal selective attention task, where low-frequency auditory (1.6 Hz) and visual (1.8 Hz) stimuli were presented simultaneously. We instructed them to either attend to the auditory or to the visual stimuli and to detect targets while ignoring the other stimulus stream. As expected, the strongest phase adjustment was observed in primary sensory regions for auditory and for visual stimulation, independent of attentional focus. We found greater differences in phase locking between attended and ignored stimulation for the visual modality. Interestingly, auditory temporal regions show small but significant attention-dependent neural entrainment even for visual stimulation. Extending findings from invasive recordings in non-human primates, we demonstrate an effect of attentional focus on the phase of the entrained oscillations in auditory and visual cortex which may be driven by phase locked increases of induced power. While sensory areas adjusted the phase of the respective stimulation frequencies, attentional focus adjusted the peak frequencies in nonsensory areas. Spatially these areas show a striking overlap with core regions of the dorsal attention network and the frontoparietal network. This suggests that these areas prioritize the attended modality by optimally exploiting the temporal structure of stimulation. Overall, our study complements and extends previous work by showing a differential effect of attentional focus on entrained oscillations (or phase adjustment) in primary sensory areas and frontoparietal areas.

Entrainment for attentional selection in Parkinson's disease

Neural entrainment plays a crucial role in perception and action, especially when stimuli possess a certain temporal regularity, and is also suggested to serve as a neural process to select and attend the relevant stream in situations where there are competing stimulus streams. Beneficial effects of entrainment have led to the suggestion that rhythmic stimuli can improve motor function in patients with Parkinson's disease (PD). Behavioural studies support this suggestion, but neurophysiological studies have shown reduced entrainment of motor areas in PD. However, oscillatory entrainment in PD has only been tested in paradigms with a single isochronous stimulus stream, whereas entrainment has an enhanced benefit in situations where one rhythmic stimulus stream has to be segregated from distractor stimuli. Therefore, we here used an intermodal selective attention task with concurrent auditory and visual stimulus streams while recording oscillatory brain activity with Magnetoencephalography (MEG). We aimed to (i) replicate earlier findings of deficient motor entrainment in PD patients in conditions where there is a single stimulus stream, and (ii) to evaluate whether increasing the benefit of entrainment by introducing a distractor stream would lead to entrainment in PD patients not seen otherwise. Contrary to this hypothesis, PD patients showed reduced motor entrainment compared to controls during both conditions, as indexed by beta oscillatory activity. These results suggest that entrainment in PD patients is deficient, even under conditions that encourage entrainment.

Distinct effects of trial-driven and task Set-related control in primary visual cortex

Task sets are task-specific configurations of cognitive processes that facilitate task-appropriate reactions to stimuli. While it is established that the trial-by-trial deployment of visual attention to expected stimuli influences neural responses in primary visual cortex (V1) in a retinotopically specific manner, it is not clear whether the mechanisms that help maintain a task set over many trials also operate with similar retinotopic specificity. Here, we address this question by using BOLD fMRI to characterize how portions of V1 that are specialized for different eccentricities respond during distinct components of an attention-demanding discrimination task: cue-driven preparation for a trial, trial-driven processing, task-initiation at the beginning of a block of trials, and task-maintenance throughout a block of trials. Tasks required either unimodal attention to an auditory or a visual stimulus or selective intermodal attention to the visual or auditory component of simultaneously presented visual and auditory stimuli. We found that while the retinotopic patterns of trial-driven and cue-driven activity depended on the attended stimulus, the retinotopic patterns of task-initiation and task-maintenance activity did not. Further, only the retinotopic patterns of trial-driven activity were found to depend on the presence of inter-modal distraction. Participants who performed well on the intermodal selective attention tasks showed strong task-specific modulations of both trial-driven and task-maintenance activity. Importantly, task-related modulations of trial-driven and task-maintenance activity were in opposite directions. Together, these results confirm that there are (at least) two different processes for top-down control of V1: One, working trial-by-trial, differently modulates activity across different eccentricity sectors – portions of V1 corresponding to different visual eccentricities. The second process works across longer epochs of task performance, and does not differ among eccentricity sectors. These results are discussed in the context of previous literature examining top-down control of visual cortical areas.

Layer Specific Sharpening of Frequency Tuning by Selective Attention in Primary Auditory Cortex

Recent electrophysiological and neuroimaging studies provide converging evidence that attending to sounds increases the response selectivity of neuronal ensembles even at the first cortical stage of auditory stimulus processing in primary auditory cortex (A1). This is achieved by enhancement of responses in the regions that process attended frequency content, and by suppression of responses in the surrounding regions. The goals of our study were to define the extent to which A1 neuronal ensembles are involved in this process, determine its effect on the frequency tuning of A1 neuronal ensembles, and examine the involvement of the different cortical layers. To accomplish these, we analyzed laminar profiles of synaptic activity and action potentials recorded in A1 of macaques performing a rhythmic intermodal selective attention task. We found that the frequency tuning of neuronal ensembles was sharpened due to both increased gain at the preferentially processed or best frequency and increased response suppression at all other frequencies when auditory stimuli were attended. Our results suggest that these effects are due to a frequency-specific counterphase entrainment of ongoing delta oscillations, which predictively orchestrates opposite sign excitability changes across all of A1. This results in a net suppressive effect due to the large proportion of neuronal ensembles that do not specifically process the attended frequency content. Furthermore, analysis of laminar activation profiles revealed that although attention-related suppressive effects predominate the responses of supragranular neuronal ensembles, response enhancement is dominant in the granular and infragranular layers, providing evidence for layer-specific cortical operations in attentive stimulus processing.

EEG frequency tagging to dissociate the cortical responses to nociceptive and nonnociceptive stimuli.

Whether the cortical processing of nociceptive input relies on the activity of nociceptive-specific neurons or whether it relies on the activity of neurons also involved in processing nonnociceptive sensory input remains a matter of debate. Here, we combined EEG "frequency tagging" of steady-state evoked potentials (SS-EPs) with an intermodal selective attention paradigm to test whether the cortical processing of nociceptive input relies on nociceptive-specific neuronal populations that can be selectively modulated by top-down attention. Trains of nociceptive and vibrotactile stimuli (Experiment 1) and trains of nociceptive and visual stimuli (Experiment 2) were applied concomitantly to the same hand, thus eliciting nociceptive, vibrotactile, and visual SS-EPs. In each experiment, a target detection task was used to focus attention toward one of the two concurrent streams of sensory input. We found that selectively attending to nociceptive or vibrotactile somatosensory input indistinctly enhances the magnitude of nociceptive and vibrotactile SS-EPs, whereas selectively attending to nociceptive or visual input independently enhances the magnitude of the SS-EP elicited by the attended sensory input. This differential effect indicates that the processing of nociceptive input involves neuronal populations also involved in the processing of touch, but distinct from the neuronal populations involved in vision.

Intermodal attention modulates visual processing in dorsal and ventral streams

Attending to visual objects while ignoring information from other modalities is necessary for performing difficult visual discriminations, but it is unclear how selecting between sensory modalities alters processing within the visual system. We used an audio-visual intermodal selective attention paradigm with fMRI to study the effects of visual attention on cortical activity in the absence of competitive interactions between multiple visual stimuli. Complex stimuli (faces and words) activated higher visual areas even in the absence of visual attention. These stimulus-dependent activations (SDAs) covered foveal retinotopic cortex, extended ventrally to the anterior fusiform gyrus and dorsally to include multiple distinct foci in the intraparietal sulcus (IPS). Attention amplified the baseline response in posterior retinotopic regions and altered activity in different ways in the extrastriate dorsal and ventral pathways. The majority of the IPS was strongly and exclusively activated by visual attention: attention-related modulations (ARMs) encompassed and spread well beyond the focal SDAs. In contrast, in the fusiform gyrus only a small subset of the regions activated by unattended stimuli showed ARMs. Ventral cortex was also heterogeneous: we found a distinct ventrolateral region in the occipitotemporal sulcus (OTS) that was activated exclusively by attention, showing neither SDAs nor any significant stimulus preferences. Attention-dependent activations in the IPS and the OTS suggest that these regions play critical roles in intermodal visual attention.

Neuronal Mechanisms and Attentional Modulation of Corticothalamic Alpha Oscillations

Field potential oscillations in the ∼10 Hz range are known as the alpha rhythm. The genesis and function of alpha has been the subject of intense investigation for the past 80 years. Whereas early work focused on the thalamus as the pacemaker of alpha rhythm, subsequent slice studies revealed that pyramidal neurons in the deep layers of sensory cortices are capable of oscillating in the alpha frequency range independently. How thalamic and cortical generating mechanisms in the intact brain might interact to shape the organization and function of alpha oscillations remains unclear. We addressed this problem by analyzing laminar profiles of local field potential and multiunit activity (MUA) recorded with linear array multielectrodes from the striate cortex of two macaque monkeys performing an intermodal selective attention task. Current source density (CSD) analysis was combined with CSD-MUA coherence to identify intracortical alpha current generators and assess their potential for pacemaking. Coherence and Granger causality analysis was applied to delineate the patterns of interaction among different alpha current generators. We found that (1) separable alpha current generators are located in superficial, granular, and deep layers, with both layer 4C and deep layers containing primary local pacemaking generators, suggesting the involvement of the thalamocortical network, and (2) visual attention reduces the magnitude of alpha oscillations as well as the level of alpha interactions, consistent with numerous reports of occipital alpha reduction with visual attention in human EEG. There is also indication that alpha oscillations in the lateral geniculate cohere with those in V1.

Attentional Modulation of Alpha Oscillations in Macaque Inferotemporal Cortex

Recent work reported the observation of alpha frequency oscillations (8-12 Hz) in several regions of macaque visual cortex, including V2, V4, and inferotemporal cortex (IT). While alpha-related physiology in V2 and V4 appears consistent with a role in attention-related suppression, in IT, alpha reactivity appears conflicted with such a role. We addressed this issue directly by analyzing laminar profiles of local field potentials and multiunit activities from the IT of macaque monkeys during performance of an intermodal selective attention task (visual versus auditory). We found that (1) before visual stimulus onset (-200 to 0 ms), attention to visual input increased ongoing alpha power in IT relative to attention to auditory input, and (2) in contrast to the prevailing view of alpha inhibition, the increased ongoing alpha activity is accompanied by increased concurrent multiunit firing and facilitates visual stimulus processing. These results suggest that ongoing alpha oscillations in IT play a different functional role than that in the occipital cortex and may be part of the neuronal mechanism representing task-relevant information.

Phonological Processing in Human Auditory Cortical Fields

We used population-based cortical-surface analysis of functional magnetic imaging data to characterize the processing of consonant–vowel–consonant syllables (CVCs) and spectrally matched amplitude-modulated noise bursts (AMNBs) in human auditory cortex as subjects attended to auditory or visual stimuli in an intermodal selective attention paradigm. Average auditory cortical field (ACF) locations were defined using tonotopic mapping in a previous study. Activations in auditory cortex were defined by two stimulus-preference gradients: (1) Medial belt ACFs preferred AMNBs and lateral belt and parabelt fields preferred CVCs. This preference extended into core ACFs with medial regions of primary auditory cortex (A1) and the rostral field preferring AMNBs and lateral regions preferring CVCs. (2) Anterior ACFs showed smaller activations but more clearly defined stimulus preferences than did posterior ACFs. Stimulus preference gradients were unaffected by auditory attention suggesting that ACF preferences reflect the automatic processing of different spectrotemporal sound features.

Shape dimensions, perceptual organization and intermodal selective attention: anterior extrastriate fMRI

Shape dimensions, perceptual organization and intermodal selective attention: anterior extrastriate fMRI

The Leading Sense: Supramodal Control of Neurophysiological Context by Attention

Attending to a stimulus enhances its neuronal representation, even at the level of primary sensory cortex. Cross-modal modulation can similarly enhance a neuronal representation, and this process can also operate at the primary cortical level. Phase reset of ongoing neuronal oscillatory activity has been shown to be an important element of the underlying modulation of local cortical excitability in both cases. We investigated the influence of attention on oscillatory phase reset in primary auditory and visual cortices of macaques performing an intermodal selective attention task. In addition to responses "driven" by preferred modality stimuli, we noted that both preferred and nonpreferred modality stimuli could "modulate" local cortical excitability by phase reset of ongoing oscillatory activity, and that this effect was linked to their being attended. These findings outline a supramodal mechanism by which attention can control neurophysiological context, thus determining the representation of specific sensory content in primary sensory cortex.

Functional Maps of Human Auditory Cortex: Effects of Acoustic Features and Attention

BackgroundWhile human auditory cortex is known to contain tonotopically organized auditory cortical fields (ACFs), little is known about how processing in these fields is modulated by other acoustic features or by attention.Methodology/Principal FindingsWe used functional magnetic resonance imaging (fMRI) and population-based cortical surface analysis to characterize the tonotopic organization of human auditory cortex and analyze the influence of tone intensity, ear of delivery, scanner background noise, and intermodal selective attention on auditory cortex activations. Medial auditory cortex surrounding Heschl's gyrus showed large sensory (unattended) activations with two mirror-symmetric tonotopic fields similar to those observed in non-human primates. Sensory responses in medial regions had symmetrical distributions with respect to the left and right hemispheres, were enlarged for tones of increased intensity, and were enhanced when sparse image acquisition reduced scanner acoustic noise. Spatial distribution analysis suggested that changes in tone intensity shifted activation within isofrequency bands. Activations to monaural tones were enhanced over the hemisphere contralateral to stimulation, where they produced activations similar to those produced by binaural sounds. Lateral regions of auditory cortex showed small sensory responses that were larger in the right than left hemisphere, lacked tonotopic organization, and were uninfluenced by acoustic parameters. Sensory responses in both medial and lateral auditory cortex decreased in magnitude throughout stimulus blocks. Attention-related modulations (ARMs) were larger in lateral than medial regions of auditory cortex and appeared to arise primarily in belt and parabelt auditory fields. ARMs lacked tonotopic organization, were unaffected by acoustic parameters, and had distributions that were distinct from those of sensory responses. Unlike the gradual adaptation seen for sensory responses, ARMs increased in amplitude throughout stimulus blocks.Conclusions/SignificanceThe results are consistent with the view that medial regions of human auditory cortex contain tonotopically organized core and belt fields that map the basic acoustic features of sounds while surrounding higher-order parabelt regions are tuned to more abstract stimulus attributes. Intermodal selective attention enhances processing in neuronal populations that are partially distinct from those activated by unattended stimuli.

Auditory Attention Activates Peripheral Visual Cortex

BackgroundRecent neuroimaging studies have revealed that putatively unimodal regions of visual cortex can be activated during auditory tasks in sighted as well as in blind subjects. However, the task determinants and functional significance of auditory occipital activations (AOAs) remains unclear.Methodology/Principal FindingsWe examined AOAs in an intermodal selective attention task to distinguish whether they were stimulus-bound or recruited by higher-level cognitive operations associated with auditory attention. Cortical surface mapping showed that auditory occipital activations were localized to retinotopic visual cortex subserving the far peripheral visual field. AOAs depended strictly on the sustained engagement of auditory attention and were enhanced in more difficult listening conditions. In contrast, unattended sounds produced no AOAs regardless of their intensity, spatial location, or frequency.Conclusions/SignificanceAuditory attention, but not passive exposure to sounds, routinely activated peripheral regions of visual cortex when subjects attended to sound sources outside the visual field. Functional connections between auditory cortex and visual cortex subserving the peripheral visual field appear to underlie the generation of AOAs, which may reflect the priming of visual regions to process soon-to-appear objects associated with unseen sound sources.

Nicotine and Attention: Event-Related Potential Investigations in Nonsmokers

Research into the effects of nicotine and smoking on cognition has largely confirmed the subjective reports of smoking in smokers on mental functions, showing smoking abstinence to disrupt and smoking/nicotine to restore cognitive functioning. Evidence of performance improvements in nonsmokers has provided partial support for the absolute effects of nicotine on cognitive processes, which are independent of withdrawal relief, but the mechanisms underlying its pro-cognitive properties still remain elusive. The attentional facilitation frequently reported with smoking/nicotine may be indirectly related to its diffuse arousal-enhancing actions, as evidenced by electroencephalographic (EEG) fast frequency power increments, or it may reflect nicotine's direct modulating effects on specific neural processes governing stimulus encoding, selection and rejection. Event-related potential (ERP) components extracted during the performance of cognitive tasks have proven to be sensitive to early pre-attentive and later attention-dependent processes that are not otherwise reflected in behavioral probes. To date, the majority of ERP studies have been conducted with smokers using passive non-task paradigms or relatively non-demanding "oddball" tasks. This paper will emphasize our recent ERP investigations with acute nicotine polacrilex (6 mg) administered to nonsmokers, and with a battery of ERP and behavioral performance paradigms focusing on intra- and inter-modal selective attention and distraction processes. These ERP findings of nicotine-augmented early attentional processing add support to the contention that nicotine may be be used by smokers as a "pharmacological tool" for tuning cognitive functions relating to the automatic and controlled aspects of sensory input detection and selection.

Paired-pulse transcranial magnetic stimulation of primary somatosensory cortex differentially modulates perception and sensorimotor transformations

Intermodal selective attention is generally associated with facilitation of relevant information. However, recent studies demonstrate reduced activation of primary somatosensory cortex (S1) with continuous vibrotactile tracking during bimodal stimulation. Reduced activation has been hypothesized to reflect an interaction between the sensorimotor and intermodal requirements of the tracking task. Recently, it has been shown that transcranial magnetic stimulation (TMS) involving a supra-threshold test stimulus (TS) preceded by a sub-threshold conditioning stimulus (CS) adversely affects tactile perception by altering excitability of local intracortical circuits. The purpose of the current paper was to use TMS to assess the effects of differential sensorimotor requirements in the right sensorimotor cortex upon local intracortical networks and sensory processing in the left primary somatosensory cortex during constant multimodal stimulation. Single and paired-pulse TMS was used to probe intracortical networks in S1 and sensory processing during a sensorimotor task where a vibrotactile stimulus to the right index finder guided either continuous or discrete sensorimotor responses of the left hand. It was hypothesized that paired-pulse TMS would alter local intracortical networks and reduce performance during the discrete sensorimotor task, but that these effects would be mitigated during the continuous sensorimotor task, possibly a reflection of reduced S1 activation observed previously during a similar continuous sensorimotor task. Regardless of sensorimotor requirements, single-pulse TMS delivered over S1 decreased sensorimotor performance. Paired-pulse TMS further decreased sensorimotor performance only when the vibrotactile stimulus guided a discrete motor response but not when it was required to continuously guide the motor response. This effect disappeared when the TS was replaced by a sub-threshold stimulus. These results suggest that the CS facilitates sensory output neurons during perceptual detection but that differential responsiveness of local cortical networks in S1 suppresses the CS effects during continuous sensory-guided movement. This study highlights the importance of sensorimotor requirements in determining the net result of task-related sensory processing in S1.

Hierarchical coupling of neuronal oscillations and their role in sensory processing

Event Abstract Back to Event Hierarchical coupling of neuronal oscillations and their role in sensory processing P. Lakatos1, 2*, G. Karmos2, 3 and C E E Schroeder1, 4 1 Nathan Kline Institute, United States 2 Hungarian Academy of Sciences, Hungary 3 Péter Pázmány Catholic University, Hungary 4 Columbia University College of Physicians and Surgeons, United States The role of neuronal oscillations in brain operations has been debated since the discovery of the electroencephalogram. Mounting evidence indicates that a key functional property of neuronal oscillations is the rhythmic shifting of excitability in local neuronal ensembles. Since changes in excitability play a key role in cortical operations, it feasible to think that oscillations play an indispensable role in sensory processing. To optimize the processing of rhythmic stimulus sequences occurring on multiple temporal scales in the world around us, spontaneous neuronal ensemble oscillations (1) must cover a wide range of frequencies, and (2) external or internal events must be able to interact with them. We analyzed laminar profiles of synaptic activity (current source density) and multiunit activity sampled during linear array multielectrode penetrations of primary auditory, visual and somatosensory cortices in awake macaques. We found that (1) intracortical oscillations are simultaneously present at multiple time-scales and are hierarchically organized. This oscillatory hierarchy controls baseline excitability and thus stimulus-related responses in a neuronal ensemble. (2) Non-specific inputs driven by sensory or motor events can reset the phase of oscillations in multiple frequency bands. By analyzing the role of intracortical oscillations in multisensory interactions and intermodal selective attention, we were able to show that modulation of the temporal structure of oscillatory activity in sensory cortices plays an instrumental role in conveying top-down and bottom-up influences on sensory processing. Conference: 10th International Conference on Cognitive Neuroscience, Bodrum, Turkey, 1 Sep - 5 Sep, 2008. Presentation Type: Oral Presentation Topic: Symposium 7: Putative mechanisms of high frequency oscillation with evidence from different species Citation: Lakatos P, Karmos G and Schroeder C (2008). Hierarchical coupling of neuronal oscillations and their role in sensory processing. Conference Abstract: 10th International Conference on Cognitive Neuroscience. doi: 10.3389/conf.neuro.09.2009.01.035 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Nov 2008; Published Online: 27 Nov 2008. * Correspondence: P. Lakatos, Nathan Kline Institute, Orangeburg, United States, plakatos@nki.rfmh.org Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers P. Lakatos G. Karmos C E E Schroeder Google P. Lakatos G. Karmos C E E Schroeder Google Scholar P. Lakatos G. Karmos C E E Schroeder PubMed P. Lakatos G. Karmos C E E Schroeder Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Synchronization of gamma band oscillations in intermodal selective attention

Synchronization of gamma band oscillations in intermodal selective attention

Attention modulates sound processing in human auditory cortex but not the inferior colliculus

Auditory attention powerfully influences perception and modulates sound processing in auditory cortex, but the extent of attentional modulation in the subcortical auditory pathway remains poorly understood. We examined the effects of intermodal attention using functional magnetic resonance imaging of the inferior colliculus and auditory cortex in a demanding intermodal selective attention task using a silent imaging paradigm designed to optimize inferior colliculus activations. Both the inferior colliculus and auditory cortex showed strong activations to sound, but attentional modulations were restricted to auditory cortex.