Yukiko Kikuchi

Newcastle University | NCL · Faculty of Medical Sciences

Learning complex ordering relationships between sensory events in a sequence is fundamental for animal perception and human communication. While it is known that rhythmic sensory events can entrain brain oscillations at different frequencies, how learning and prior experience with sequencing relationships affect neocortical oscillations and neurona...

In the ventral stream of the primate auditory cortex, cortico-cortical projections emanate from the primary auditory cortex (AI) along 2 principal axes: one mediolateral, the other caudorostral. Connections in the mediolateral direction from core, to belt, to parabelt, have been well described, but less is known about the flow of information along...

It is generally held that non-primary sensory regions of the brain have a strong impact on frontal cortex. However, the effective connectivity of pathways to frontal cortex is poorly understood. Here we microstimulate sites in the superior temporal and ventral frontal cortex of monkeys and use functional magnetic resonance imaging to evaluate the f...

In the introduction to this theme issue, Honing et al. suggest that the origins of musicality-the capacity that makes it possible for us to perceive, appreciate and produce music-can be pursued productively by searching for components of musicality in other species. Recent studies have highlighted that the behavioural relevance of stimuli to animal...

In the primate auditory cortex, information flows serially in the mediolateral dimension from core, to belt, to parabelt. In the caudorostral dimension, stepwise serial projections convey information through the primary, rostral, and rostrotemporal (AI, R, and RT) core areas on the supratemporal plane (STP), continuing to the rostrotemporal polar a...

Background: Significant progress has been made in elucidating the genetic underpinning of Autism Spectrum Disorder (ASD). This childhood-onset chronic disorder of cognition, communication and behaviour ranks among the most severe from a public health perspective, and it is therefore hoped that new discoveries will lead to better therapeutic options...

The human brain extracts meaning using an extensive neural system for semantic knowledge. Whether broadly distributed systems depend on or can compensate after losing a highly interconnected hub is controversial. We report intracranial recordings from two patients during a speech prediction task, obtained minutes before and after neurosurgical trea...

Activity-induced gene expression underlies synaptic plasticity and brain function. Here, using molecular sequencing techniques, we define activity-dependent transcriptomic and epigenomic changes at the tissue and single-cell level in the human brain following direct electrical stimulation of the anterior temporal lobe in patients undergoing neurosu...

The perception of pitch is a fundamental percept, which is mediated by the auditory system, requiring the abstraction of stimulus properties related to the spectro-temporal structure of sound. Despite its importance, there is still debate as to the precise areas responsible for its encoding, which may be due to species differences or differences in...

The hippocampus plays a key role in integrating spatial and temporal information, however, in natural scenarios different rules apply under different contexts. Contextual information could be hippocampal dependent, if it is integrated into a context-guided memory sequence (Eichenbaum, 2017: PMID 28655882). The prefrontal cortex could also be involv...

Understanding how the brain represents and binds complex information distributed over time is a challenging problem, requiring computationally and neurobiologically informed approaches to solve. Human language is a salient example, whereby syntactic knowledge facilitates “movement” and transformation of sequential information into hierarchical ment...

The human brain extracts meaning from the world using an extensive neural system for semantic knowledge. Whether such broadly distributed systems crucially depend on or can compensate for the loss of one of their highly interconnected hubs is controversial. The strongest level of causal evidence for the role of a brain hub is to evaluate its acute...

We recorded neural responses in human participants to three types of pitch-evoking regular stimuli at rates below and above the lower limit of pitch using magnetoencephalography (MEG). These bandpass filtered (1–4 kHz) stimuli were harmonic complex tones (HC), click trains (CT), and regular interval noise (RIN). Trials consisted of noise-regular-no...

The perception of pitch requires the abstraction of stimulus properties related to the spectrotemporal structure of sound. Previous studies utilizing both animal electrophysiology and human imaging have indicated the presence of a center for pitch representation in the auditory cortex. Recent data from our own group - examining local field potentia...

Figure-ground segregation, the brain’s ability to group related features into stable perceptual entities, is crucial for auditory perception in noisy environments. The neuronal mechanisms for this process are poorly understood in the auditory system. Here, we report figure-ground modulation of multi-unit activity (MUA) in the primary and non-primar...

Information from Magnetic Resonance Imaging (MRI) is useful for diagnosis and treatment management of human neurological patients. MRI monitoring might also prove useful for non-human animals involved in neuroscience research provided that MRI is available and feasible and that there are no MRI contra-indications precluding scanning. However, MRI m...

Human brain pathways supporting language and declarative memory are thought to have differentiated substantially during evolution. However, cross-species comparisons are missing on site-specific effective connectivity between regions important for cognition. We harnessed functional imaging to visualize the effects of direct electrical brain stimula...

Cognitive pathways supporting human language and declarative memory are thought to have uniquely evolutionarily differentiated in our species. However, cross-species comparisons are missing on site-specific effective connectivity between regions important for cognition. We harnessed a new approach using functional imaging to visualize the impact of...

Figure-ground segregation, the brain’s ability to group related features into stable perceptual entities, is crucial for auditory perception in noisy environments. The neuronal mechanisms for this process are poorly understood in the auditory system. Here, we report figure-ground modulation of multi-unit activity (MUA) in the primary and non-primar...

Understanding how the brain forms representations of structured information distributed in time is a challenging endeavour for the neuroscientific community, requiring computationally and neurobiologically informed approaches. The neural mechanisms for segmenting continuous streams of sensory input and establishing representations of dependencies r...

Understanding how the brain binds complex information distributed over time is a challenging problem facing the neuroscientific community, requiring computationally and neurobiologically informed approaches to solve. The combinatorial binding problem is particularly salient in language, whereby human syntactic knowledge supports the encoding and de...

In this study, we show direct electrophysiological evidence of figure-ground segregation in primary and non-primary auditory cortex, with a systematic effect of figure saliency in the anterior, non-primary areas.

This work sought correlates of pitch perception, defined by neural activity above the lower limit of pitch (LLP), in auditory cortical neural ensembles, and examined their topographical distribution. Local field potentials (LFPs) were recorded in eight patients undergoing invasive recordings for pharmaco-resistant epilepsy. Stimuli consisted of bur...

Efficient perception in natural environments depends on neural interactions between voluntary processes within cognitive control, such as attention, and those that are automatic and subconscious, such as brain adaptation to predictable input (also called repetition suppression). Although both attention and adaptation have been studied separately an...

Segregating the key features of the natural world within crowded visual or sound scenes is a critical aspect of everyday perception. The neurobiological bases for auditory figure-ground segregation are poorly understood. We demonstrate that macaques perceive an acoustic figure-ground stimulus with comparable performance to humans using a neural sys...

Animals and humans rapidly detect specific features of sounds, but the time courses of the underlying neural response for different stimulus categories is largely unknown. Furthermore, the intricate functional organization of auditory information processing pathways is poorly understood. Here, we computed neuronal response latencies from simultaneo...

Predicting the occurrence of future events from prior ones is vital for animal perception and cognition. Although how such sequence learning (a form of relational knowledge) relates to particular operations in language remains controversial, recent evidence shows that sequence learning is disrupted in frontal lobe damage associated with aphasia. Al...

Interdisciplinary perspectives on the capacity to perceive, appreciate, and make music. Research shows that all humans have a predisposition for music, just as they do for language. All of us can perceive and enjoy music, even if we can't carry a tune and consider ourselves “unmusical.” This volume offers interdisciplinary perspectives on the capac...

(a) Distribution of retrogradely labeled neurons in thalamus following injections into the auditory cortical areas of the STP and, for comparison, the STGr. The following cases were combined for each cortical area (see Table 3 for individual injections): AI 1–3; R 4–6; RT 7–9; RTp 11–15; STGr/TGdg, 16. Case 10 was excluded because it could not be d...

Distributions of frequency of phase and amplitude for the PAC response in humans and monkeys. The distributions of peak PAC values were calculated per phase (A, C) or amplitude (B, D) separately. The error bars denote the standard deviation. No obvious differences are seen between the results in the two monkeys or the two humans. (TIF)

Topography of PAC frequency of phase and amplitude in human Heschl’s Gyrus. The distributions of peak PAC values were calculated at postero-medial (blue) and antero-lateral (red) recording sites separately per phase (A, C) or amplitude (B, D). The error bars denote the standard deviation. The boundaries in the two subjects between the postero-media...

Control experiment in human participant H3 and resulting PAC effects. A. Time course of the experiments. The testing conditions were identical, with the key difference what the subject experienced before testing: either exposure to random transitions between the nonsense words in a sequence or structured sequences consistent with the artificial gra...

Control experiment in human participant H3 and resulting PAC effects. Number of sites with significant PAC responses and sequencing context PAC effects during the same type of testing phase after exposure to structured sequences consistent with the AG ordering relationships. (XLSX)

Effects of the acoustical elements preceding the probe stimulus analysis window. (DOCX)

Artificial grammar sequences and recording sites. A. Artificial grammar exposure and testing sequences. This figure shows the composition of all of the exposure and testing sequences used in these experiments. The letters (A, C, D, F, G) represent the specific nonsense words in the sequences (see manuscript Materials and Methods). First, eight expo...

Lack of relationship between sequencing context sensitive neural effects and auditory cortex topography. (DOCX)

Exposure to random transitions or structured sequence ordering relationships: Control experiment in human participant (H3). (DOCX)

Correlation analysis between the magnitude of the response to the sounds preceding the probe stimulus window (x-axis) and the magnitude of the sequencing context effect during the probe stimulus (y-axis) for LFP power. The data from high-gamma, low-gamma, and theta bands are displayed here together as the results were comparable for the separate fr...

Monkey and human auditory cortex fMRI responses (data re-analyzed from Wilson et al., Nature Communications, 2015 [20]) do not show strong sequencing context sensitivity. The analyses performed in Wilson et al. (2015 [20]) report no significant activation to the violation vs consistent contrast within auditory cortex in either the macaque or human...

Behavioral results on the AGL paradigm in human patient (H1) after the surgical monitoring period. A. Reaction times after offset of the testing sequences for which a correct response was given were significantly shorter in reaction time (RT) to the violation sequences compared to the consistent sequences (consistent: 1.5 ± 0.8 secs in 55 trials ou...

Exemplary ERP, EPR-subtracted LFP, phase-amplitude coupling (PAC), and inter-trial phase coherence (ITC) responses. A. An exemplary averaged monkey LFP response (ERP) to the violation (left column) and the consistent sequence (right column). The horizontal color keys above the response curve identify the time of occurrence of the elements in the se...

Tonotopic maps and locations of significant sequencing context effects. A. Tonotopic maps based on fMRI (left) and electrophysiological recordings (right) of two animals. The fMRI image on the left shows a slice looking down on the supratemporal plane. B. Recording sites that showed sequencing context effects across all LFP signals (theta, low-gamm...

Control experiment in human participant H3 and resulting PAC effects. Number of sites with significant PAC responses and sequencing context PAC effects during the same type of testing after exposure to sequences containing random transitions between the nonsense words. (XLSX)

An evolutionary account of human language as a neurobiological system must distinguish between human-unique neurocognitive processes supporting language and evolutionarily conserved, domain-general processes that can be traced back to our primate ancestors. Neuroimaging studies across species may determine whether candidate neural processes are sup...

An evolutionary account of human language as a neurobiological system must distinguish between human-unique neurocognitive processes supporting language and evolutionarily conserved, domain-general processes that can be traced back to our primate ancestors. Neuroimaging studies across species may determine whether candidate neural processes are sup...

Electroencephalography (EEG) has identified human brain potentials elicited by Artificial Grammar (AG) learning paradigms, which present participants with rule-based sequences of stimuli. Nonhuman animals are sensitive to certain AGs; therefore, evaluating which EEG Event Related Potentials (ERPs) are associated with AG learning in nonhuman animals...

Many speech sounds and animal vocalizations contain components, referred to as complex tones, that consist of a fundamental frequency (F0) and higher harmonics. In this study we examined single-unit activity recorded in the core (A1) and lateral belt (LB) areas of auditory cortex in two rhesus monkeys as they listened to pure tones and pitch-shifte...

Artificial grammars (AG) are designed to emulate aspects of the structure of language, and AG learning (AGL) paradigms can be used to study the extent of nonhuman animals' structure-learning capabilities. However, different AG structures have been used with nonhuman animals and are difficult to compare across studies and species. We developed a sim...

Artificial grammars (AG) are designed to emulate aspects of the structure of language, and AG learning (AGL) paradigms can be used to study the extent of nonhuman animals' structure-learning capabilities. However, different AG structures have been used with nonhuman animals and are difficult to compare across studies and species. We developed a sim...

Connectional anatomical evidence suggests that the auditory core, containing the tonotopic areas A1, R, and RT, constitutes the first stage of auditory cortical processing, with feedforward projections from core outward, first to the surrounding auditory belt and then to the parabelt. Connectional evidence also raises the possibility that the core...

The dorsolateral area of the prefrontal cortex (PFC) in primates is involved in visuospatial working memory, but the cellular basis of spatial working memory for auditory information is poorly understood. Here we examined dorsolateral PFC neurons using visual and auditory oculomotor delayed-response tasks. We found that the dorsolateral PFC contain...

This chapter summarizes that iontophoretic application of the α2-receptor antagonist yohimbine to prefrontal neurons in the monkey attenuated delay-period activity, indicating that activation of α2 receptors plays a critical role in maintaining the directional or mnemonic coding of prefrontal neurons. Of 57 neurons recorded during oculomotor delaye...