Background: Autism is a developmental disorder characterised by changes in social, communication, and behavioural performance. Assistance dogs can support children with autism to engage in everyday occupations. Despite more children being partnered with assistance dogs, there is limited research regarding the impact of assistance dogs on the occupational engagement of children with autism and their families, and further research is needed to fully understand the impact of this type of support within the Australian context.
View Article and Find Full Text PDFCerebellar degeneration (CD) has deleterious effects on speech motor behavior. Recently, a dissociation between feedback and feedforward control of speaking was observed in CD: Whereas CD patients exhibited reduced adaptation across trials to consistent formant feedback alterations, they showed enhanced within-trial compensation for unpredictable formant feedback perturbations. In this study, it was found that CD patients exhibit abnormally increased within-trial vocal compensation responses to unpredictable pitch feedback perturbations.
View Article and Find Full Text PDFPrevious studies have established a role for premotor cortex in the processing of auditory emotional vocalizations. Inhibitory continuous theta burst transcranial magnetic stimulation (cTBS) applied to right premotor cortex selectively increases the reaction time to a same-different task, implying a causal role for right ventral premotor cortex (PMv) in the processing of emotional sounds. However, little is known about the functional networks to which PMv contribute across the cortical hemispheres.
View Article and Find Full Text PDFAltering reafferent sensory information can have a profound effect on motor output. Introducing a short delay [delayed auditory feedback (DAF)] during speech production results in modulations of voice and loudness, and produces a range of speech dysfluencies. The ability of speakers to resist the effects of delayed feedback is variable yet it is unclear what neural processes underlie differences in susceptibility to DAF.
View Article and Find Full Text PDFThe cerebellum has been hypothesized to form a crucial part of the speech motor control network. Evidence for this comes from patients with cerebellar damage, who exhibit a variety of speech deficits, as well as imaging studies showing cerebellar activation during speech production in healthy individuals. To date, the precise role of the cerebellum in speech motor control remains unclear, as it has been implicated in both anticipatory (feedforward) and reactive (feedback) control.
View Article and Find Full Text PDFNeuroimaging studies of speech perception have consistently indicated a left-hemisphere dominance in the temporal lobes' responses to intelligible auditory speech signals (McGettigan and Scott, 2012). However, there are important communicative cues that cannot be extracted from auditory signals alone, including the direction of the talker's gaze. Previous work has implicated the superior temporal cortices in processing gaze direction, with evidence for predominantly right-lateralized responses (Carlin & Calder, 2013).
View Article and Find Full Text PDFUnlabelled: Synchronized behavior (chanting, singing, praying, dancing) is found in all human cultures and is central to religious, military, and political activities, which require people to act collaboratively and cohesively; however, we know little about the neural underpinnings of many kinds of synchronous behavior (e.g., vocal behavior) or its role in establishing and maintaining group cohesion.
View Article and Find Full Text PDFSpoken conversations typically take place in noisy environments, and different kinds of masking sounds place differing demands on cognitive resources. Previous studies, examining the modulation of neural activity associated with the properties of competing sounds, have shown that additional speech streams engage the superior temporal gyrus. However, the absence of a condition in which target speech was heard without additional masking made it difficult to identify brain networks specific to masking and to ascertain the extent to which competing speech was processed equivalently to target speech.
View Article and Find Full Text PDFHumans can generate mental auditory images of voices or songs, sometimes perceiving them almost as vividly as perceptual experiences. The functional networks supporting auditory imagery have been described, but less is known about the systems associated with interindividual differences in auditory imagery. Combining voxel-based morphometry and fMRI, we examined the structural basis of interindividual differences in how auditory images are subjectively perceived, and explored associations between auditory imagery, sensory-based processing, and visual imagery.
View Article and Find Full Text PDFLang Cogn Neurosci
October 2014
This study focuses on the neural processing of English sentences containing unergative, unaccusative and transitive verbs. We demonstrate common responses in bilateral superior temporal gyri in response to listening to sentences containing unaccusative and transitive verbs compared to unergative verbs; we did not detect any activation that was specific to unaccusatives. Our findings indicate that the neural processing of unaccusative and transitive verbs is highly similar, and very different from the processing of unergative verbs.
View Article and Find Full Text PDFThe melodic contour of speech forms an important perceptual aspect of tonal and nontonal languages and an important limiting factor on the intelligibility of speech heard through a cochlear implant. Previous work exploring the neural correlates of speech comprehension identified a left-dominant pathway in the temporal lobes supporting the extraction of an intelligible linguistic message, whereas the right anterior temporal lobe showed an overall preference for signals clearly conveying dynamic pitch information [Johnsrude, I. S.
View Article and Find Full Text PDFHumans express laughter differently depending on the context: polite titters of agreement are very different from explosions of mirth. Using functional MRI, we explored the neural responses during passive listening to authentic amusement laughter and controlled, voluntary laughter. We found greater activity in anterior medial prefrontal cortex (amPFC) to the deliberate, Emitted Laughs, suggesting an obligatory attempt to determine others' mental states when laughter is perceived as less genuine.
View Article and Find Full Text PDFHistorically, the study of human identity perception has focused on faces, but the voice is also central to our expressions and experiences of identity [Belin, P., Fecteau, S., & Bedard, C.
View Article and Find Full Text PDFProduction of actions is highly dependent on concurrent sensory information. In speech production, for example, movement of the articulators is guided by both auditory and somatosensory input. It has been demonstrated in non-human primates that self-produced vocalizations and those of others are differentially processed in the temporal cortex.
View Article and Find Full Text PDFMirror neurons are single cells found in macaque premotor and parietal cortices that are active during action execution and observation. In non-human primates, mirror neurons have only been found in relation to object-directed movements or communicative gestures, as non-object directed actions of the upper limb are not well characterized in non-human primates. Mirror neurons provide important evidence for motor simulation theories of cognition, sometimes referred to as the direct matching hypothesis, which propose that observed actions are mapped onto associated motor schemata in a direct and automatic manner.
View Article and Find Full Text PDFThe question of hemispheric lateralization of neural processes is one that is pertinent to a range of subdisciplines of cognitive neuroscience. Language is often assumed to be left-lateralized in the human brain, but there has been a long running debate about the underlying reasons for this. We addressed this problem with fMRI by identifying the neural responses to amplitude and spectral modulations in speech and how these interact with speech intelligibility to test previous claims for hemispheric asymmetries in acoustic and linguistic processes in speech perception.
View Article and Find Full Text PDFSeveral perspectives on speech perception posit a central role for the representation of articulations in speech comprehension, supported by evidence for premotor activation when participants listen to speech. However, no experiments have directly tested whether motor responses mirror the profile of selective auditory cortical responses to native speech sounds or whether motor and auditory areas respond in different ways to sounds. We used fMRI to investigate cortical responses to speech and nonspeech mouth (ingressive click) sounds.
View Article and Find Full Text PDFPrevious investigation of CA1-evoked subicular responses has used either single low-frequency pulses (LF), paired-pulses (PP), or high-frequency bursts. Here we test for the first time how subiculum responds to naturalistic stimulation trains (NSTs). We recorded CA1-evoked field potentials from dorsal rat subiculum in response to LF, PP, and two NST patterns.
View Article and Find Full Text PDFFunctional imaging studies have revealed roles for orbitofrontal cortex (OFC) in reward processing and decision making. In many situations, rewards signal that the current behavior should be maintained, whereas punishments cue a change in behavior. Thus, hedonic responses to reinforcers are conflated with their function as behavioral cues.
View Article and Find Full Text PDFThere is common neural activity in parietal and premotor cortex when executing and observing goal-directed movements: the "mirror" response. In addition, active and passive limb movements cause overlapping activity in premotor and somatosensory cortex. This association of motor and sensory activity cannot ascribe agency, the ability to discriminate between self- and non-self-generated events.
View Article and Find Full Text PDFFunctional imaging studies in recent years have confirmed the involvement of orbitofrontal cortex (OFC) in human reward processing and have suggested that OFC responses are context-dependent. A seminal electrophysiological experiment in primates taught animals to associate abstract visual stimuli with differently valuable food rewards. Subsequently, pairs of these learned abstract stimuli were presented and firing of OFC neurons to the medium-value stimulus was measured.
View Article and Find Full Text PDFElectrophysiological data confirm the existence of neurons that respond to both motor and sensory events in the macaque brain. These mirror neurons respond to execution and observation of goal-orientated actions. It has been suggested that they comprise a neural basis for encoding an internal representation of action.
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