scholarly journals Modulation of tonotopic ventral MGB is behaviorally relevant for speech recognition

2019 ◽  
Author(s):  
Paul Glad Mihai ◽  
Michelle Moerel ◽  
Federico de Martino ◽  
Robert Trampel ◽  
Stefan Kiebel ◽  
...  
Keyword(s):  
Speech Recognition ◽  
High Field ◽  
Recognition Performance ◽  
Medial Geniculate Body ◽  
Auditory Pathway ◽  
Human Cognition ◽  
Ultra High Field ◽  
Medial Geniculate ◽  
Sensory Pathway ◽  
7T Fmri

AbstractSensory thalami are central sensory pathway stations for information processing. Their role for human cognition and perception, however, remains unclear. Recent evidence suggests a specific involvement of the sensory thalami in speech recognition. In particular, the auditory thalamus (medial geniculate body, MGB) response is modulated by speech recognition tasks and the amount of this task-dependent modulation is associated with speech recognition abilities. Here we tested the specific hypothesis that this behaviorally relevant modulation is present in the MGB subsection that corresponds to the primary auditory pathway (i.e., the ventral MGB [vMGB]). We used ultra-high field 7T fMRI to identify the vMGB, and found a significant positive correlation between the amount of task-dependent modulation and the speech recognition performance across participants within left vMGB, but not within the other MGB subsections. These results imply that modulation of thalamic driving input to the auditory cortex facilitates speech recognition.

scholarly journals Modulation of tonotopic ventral medial geniculate body is behaviorally relevant for speech recognition

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Paul Glad Mihai ◽  
Michelle Moerel ◽  
Federico de Martino ◽  
Robert Trampel ◽  
Stefan Kiebel ◽  
...  
Keyword(s):  
Speech Recognition ◽  
High Field ◽  
Recognition Performance ◽  
Medial Geniculate Body ◽  
Auditory Pathway ◽  
Human Cognition ◽  
Ultra High Field ◽  
Medial Geniculate ◽  
Sensory Pathway ◽  
7T Fmri

Sensory thalami are central sensory pathway stations for information processing. Their role for human cognition and perception, however, remains unclear. Recent evidence suggests an involvement of the sensory thalami in speech recognition. In particular, the auditory thalamus (medial geniculate body, MGB) response is modulated by speech recognition tasks and the amount of this task-dependent modulation is associated with speech recognition abilities. Here, we tested the specific hypothesis that this behaviorally relevant modulation is present in the MGB subsection that corresponds to the primary auditory pathway (i.e., the ventral MGB [vMGB]). We used ultra-high field 7T fMRI to identify the vMGB, and found a significant positive correlation between the amount of task-dependent modulation and the speech recognition performance across participants within left vMGB, but not within the other MGB subsections. These results imply that modulation of thalamic driving input to the auditory cortex facilitates speech recognition.

scholarly journals Modulation of the primary auditory thalamus when recognising speech in noise

2019 ◽  
Author(s):  
Paul Glad Mihai ◽  
Nadja Tschentscher ◽  
Katharina von Kriegstein
Keyword(s):  
Speech Signal ◽  
Medial Geniculate Body ◽  
Auditory Pathway ◽  
Constant Stimulus ◽  
Stimulus Properties ◽  
Bayesian Brain ◽  
Speech In Noise ◽  
Medial Geniculate ◽  
Sensory Pathway ◽  
Sensory Uncertainty

AbstractRecognising speech in background noise is a strenuous daily activity, yet most humans can master it. A mechanistic explanation of how the human brain deals with such sensory uncertainty is the Bayesian Brain Hypothesis. In this view, the brain uses a dynamic generative model to simulate the most likely trajectory of the speech signal. Such simulation account can explain why there is a task-dependent modulation of sensory pathway structures (i.e., the sensory thalami) for recognition tasks that require tracking of fast-varying stimulus properties (i.e., speech) in contrast to relatively constant stimulus properties (e.g., speaker identity) despite the same stimulus input. Here we test the specific hypothesis that this task-dependent modulation for speech recognition increases in parallel with the sensory uncertainty in the speech signal. In accordance with this hypothesis, we show—by using ultra-high-resolution functional magnetic resonance imaging in human participants—that the task-dependent modulation of the left primary sensory thalamus (ventral medial geniculate body, vMGB) for speech is particularly strong when recognizing speech in noisy listening conditions in contrast to situations where the speech signal is clear. Exploratory analyses showed that this finding was specific to the left vMGB; it was not present in the midbrain structure of the auditory pathway (left inferior colliculus, IC). The results imply that speech in noise recognition is supported by modifications at the level of the subcortical sensory pathway providing driving input to the auditory cortex.

Vestibulothalamic projections in man--a sixth primary sensory pathway

1978 ◽  
Vol 41 (2) ◽  
pp. 394-401 ◽  
Author(s):  
P. A. Hawrylyshyn ◽  
A. M. Rubin ◽  
R. R. Tasker ◽  
L. W. Organ ◽  
J. M. Fredrickson
Keyword(s):  
Red Nucleus ◽  
Medial Geniculate Body ◽  
Auditory Pathway ◽  
Neurosurgical Procedures ◽  
Medial Lemniscus ◽  
Cortical Projection ◽  
Human Thalamus ◽  
Medial Geniculate ◽  
Processing Information ◽  
Sensory Pathway

1. Responses suggesting activation of the vestibular system, elicited by electrical stimulation of the human thalamus during 22 routine stereotaxic neurosurgical procedures, were examined in a retrospective study to determine the possible existence of vestibulothalamo-cortical projections in man. 2. Such responses were most frequently described as sensations of movement through space and were associated with two distinct vestibulothalamic projections: a) an anterior relay was situated ventral to the medial lemniscus, passing lateral to the red nucleus and dorsal to the subthalamic nucleus prior to terminating in the nucleus ventrointermedius (Vim) (comparable to VPLo in primates); b) a posterior relay associated with the auditory pathway (lateral lemniscus and brachium of the inferior colliculus) projected to the medial geniculate body. 3. The production of sensations of motion in conscious patients by stimulating areas that are similar to those reported constituting vestibulothalamic pathways in cats and primates implies a distinct primary sensory cortical projection for processing information from the vestibular receptors pertaining to the recognition of spatial movements.

scholarly journals Cochlear Synaptopathy: A Primary Factor Affecting Speech Recognition Performance in Presbycusis

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Zhe Chen ◽  
Yanmei Zhang ◽  
Junbo Zhang ◽  
Rui Zhou ◽  
Zhen Zhong ◽  
...  
Keyword(s):  
Speech Recognition ◽  
Action Potential ◽  
Animal Studies ◽  
Signal To Noise Ratio ◽  
Recognition Performance ◽  
Auditory Pathway ◽  
Auditory Brainstem ◽  
Auditory Brainstem Responses ◽  
Hearing Ability ◽  
Summating Potential

The results of recent animal studies have suggested that cochlear synaptopathy may be an important factor involved in presbycusis. Therefore, here, we aimed to examine whether cochlear synaptopathy frequently exists in patients with presbycusis and to describe the effect of cochlear synaptopathy on speech recognition in noise. Based on the medical history and an audiological examination, 94 elderly patients with bilateral, symmetrical, sensorineural hearing loss were diagnosed as presbycusis. An electrocochleogram, auditory brainstem responses, auditory cortical evoked potentials, and speech audiometry were recorded to access the function of the auditory pathway. First, 65 ears with hearing levels of 41-50 dB HL were grouped based on the summating potential/action potential (SP/AP) ratio, and the amplitudes of AP and SP were compared between the two resulting groups. Second, 188 ears were divided into two groups: the normal SP/AP and abnormal SP/AP groups. The speech recognition abilities in the two groups were compared. Finally, the relationship between abnormal electrocochleogram and poor speech recognition (signal-to-noise ratio loss ≥7 dB) was analyzed in 188 ears. The results of the present study showed: (1) a remarkable reduction in the action potential amplitude was observed in patients with abnormal SP/AP ratios; this suggests that cochlear synaptopathy was involved in presbycusis. (2) There was a large proportion of patients with poor speech recognition in the abnormal SP/AP group. Furthermore, a larger number of cases with abnormal SP/AP ratios were confirmed among patients with presbycusis and poor speech recognition. We concluded that cochlear synaptopathy is not uncommon among elderly individuals who have hearing ability deficits, and it may have a more pronounced effect on ears with declining auditory performance in noisy environments.

scholarly journals Task-Dependent Modulation of Medial Geniculate Body Is Behaviorally Relevant for Speech Recognition

2008 ◽  
Vol 18 (23) ◽  
pp. 1855-1859 ◽  
Author(s):  
Katharina von Kriegstein ◽  
Roy D. Patterson ◽  
T.D. Griffiths
Keyword(s):  
Speech Recognition ◽  
Medial Geniculate Body ◽  
Medial Geniculate

scholarly journals Auditory thalamus dysfunction and pathophysiology in tinnitus: a predictive network hypothesis

2021 ◽  
Author(s):  
Pia Brinkmann ◽  
Sonja A. Kotz ◽  
Jasper V. Smit ◽  
Marcus L. F. Janssen ◽  
Michael Schwartze
Keyword(s):  
Auditory Processing ◽  
Treatment Options ◽  
Medial Geniculate Body ◽  
Auditory Pathway ◽  
Temporal Adaptation ◽  
Input Signals ◽  
Medial Geniculate ◽  
Auditory Cortices ◽  
Sound Features ◽  
Thalamic Function

AbstractTinnitus is the perception of a ‘ringing’ sound without an acoustic source. It is generally accepted that tinnitus develops after peripheral hearing loss and is associated with altered auditory processing. The thalamus is a crucial relay in the underlying pathways that actively shapes processing of auditory signals before the respective information reaches the cerebral cortex. Here, we review animal and human evidence to define thalamic function in tinnitus. Overall increased spontaneous firing patterns and altered coherence between the thalamic medial geniculate body (MGB) and auditory cortices is observed in animal models of tinnitus. It is likely that the functional connectivity between the MGB and primary and secondary auditory cortices is reduced in humans. Conversely, there are indications for increased connectivity between the MGB and several areas in the cingulate cortex and posterior cerebellar regions, as well as variability in connectivity between the MGB and frontal areas regarding laterality and orientation in the inferior, medial and superior frontal gyrus. We suggest that these changes affect adaptive sensory gating of temporal and spectral sound features along the auditory pathway, reflecting dysfunction in an extensive thalamo-cortical network implicated in predictive temporal adaptation to the auditory environment. Modulation of temporal characteristics of input signals might hence factor into a thalamo-cortical dysrhythmia profile of tinnitus, but could ultimately also establish new directions for treatment options for persons with tinnitus.

scholarly journals Layer-specific ultra-high field 7T fMRI showing that threat anticipation is mediated by the pulvinar input to the superficial layers of primary visual cortex (V1)

2018 ◽  
Author(s):  
Ai Koizumi ◽  
Minye Zhan ◽  
Hiroshi Ban ◽  
Ikuhiro Kida ◽  
Federico de Martino ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Visual Processing ◽  
High Field ◽  
Specific Interaction ◽  
Ultra High Field ◽  
Happy Face ◽  
Face Target ◽  
Fearful Face ◽  
Early Visual Cortex ◽  
7T Fmri

AbstractThe perceptual system gives priority to threat-relevant signals with survival value. Its mechanism may not only include the processing initiated in the presence of threat signals but also in the mere anticipation of such signals. Here, we show that the pulvinar modulates activity in the early visual cortex (V1) specifically in threat anticipation. Using ultra-high-field 7T fMRI, we examined the layer-specific interaction between V1 and the pulvinar, while taking advantage of the fact that the directionality of such interaction is anatomically constrained in specific V1 layers. Only in anticipation of a fearful face target, but not of a control happy face target, was false perception of anticipated-yet-unpresented target face accompanied by stronger activity in the V1 superficial-cortical-depth (layers 1-3), which was preceded by pre-target-onset pulvinar activity. The pulvinar may contribute to the visual processing initiated in the anticipation of threat, and play an important role in anxiety.

scholarly journals Sound Repetition Rate in the Human Auditory Pathway: Representations in the Waveshape and Amplitude of fMRI Activation

2002 ◽  
Vol 88 (3) ◽  
pp. 1433-1450 ◽  
Author(s):  
Michael P. Harms ◽  
Jennifer R. Melcher
Keyword(s):  
Auditory Cortex ◽  
Inferior Colliculus ◽  
Repetition Rate ◽  
Neural Coding ◽  
Medial Geniculate Body ◽  
Auditory Pathway ◽  
Stream Segregation ◽  
Neural Representation ◽  
Systematic Change ◽  
Medial Geniculate

Sound repetition rate plays an important role in stream segregation, temporal pattern recognition, and the perception of successive sounds as either distinct or fused. This study was aimed at elucidating the neural coding of repetition rate and its perceptual correlates. We investigated the representations of rate in the auditory pathway of human listeners using functional magnetic resonance imaging (fMRI), an indicator of population neural activity. Stimuli were trains of noise bursts presented at rates ranging from low (1–2/s; each burst is perceptually distinct) to high (35/s; individual bursts are not distinguishable). There was a systematic change in the form of fMRI response rate-dependencies from midbrain to thalamus to cortex. In the inferior colliculus, response amplitude increased with increasing rate while response waveshape remained unchanged and sustained. In the medial geniculate body, increasing rate produced an increase in amplitude and a moderate change in waveshape at higher rates (from sustained to one showing a moderate peak just after train onset). In auditory cortex (Heschl's gyrus and the superior temporal gyrus), amplitude changed somewhat with rate, but a far more striking change occurred in response waveshape—low rates elicited a sustained response, whereas high rates elicited an unusual phasic response that included prominent peaks just after train onset and offset. The shift in cortical response waveshape from sustained to phasic with increasing rate corresponds to a perceptual shift from individually resolved bursts to fused bursts forming a continuous (but modulated) percept. Thus at high rates, a train forms a single perceptual “event,” the onset and offset of which are delimited by the on and off peaks of phasic cortical responses. While auditory cortex showed a clear, qualitative correlation between perception and response waveshape, the medial geniculate body showed less correlation (since there was less change in waveshape with rate), and the inferior colliculus showed no correlation at all. Overall, our results suggest a population neural representation of the beginning and the end of distinct perceptual events that is weak or absent in the inferior colliculus, begins to emerge in the medial geniculate body, and is robust in auditory cortex.

Sign in / Sign up

Export Citation Format

Share Document