Makoto Kusunoki

Medical Research Council (UKRI) | mrc · MRC Cognition and Brain Sciences Unit

Cognitive flexibility requires both the encoding of task-relevant and the ignoring of task-irrelevant stimuli. While the neural coding of task-relevant stimuli is increasingly well understood, the mechanisms for ignoring task-irrelevant stimuli remain poorly understood. Here, we study how task performance and biological constraints jointly determin...

Cognitive flexibility requires both the encoding of task-relevant and the ignoring of task-irrelevant stimuli. While the neural coding of task-relevant stimuli is increasingly well understood, the mechanisms for ignoring task-irrelevant stimuli remain poorly understood. Here, we study how task performance and biological constraints jointly determin...

While classic views proposed that working memory (WM) is mediated by sustained firing, recent evidence suggests a contribution of activity-silent states. Within WM, human neuroimaging studies suggest a switch between attentional foreground and background, with only the foregrounded item represented in active neural firing. To address this process a...

Cognitive flexibility requires both the encoding of task-relevant and the ignoring of task-irrelevant stimuli. While the neural coding of task-relevant stimuli is increasingly well understood, the mechanisms for ignoring task-irrelevant stimuli remain poorly understood. Here, we study how task performance and biological constraints jointly determin...

Ventrolateral prefrontal cortex (vlPFC), dorsolateral prefrontal cortex (dlPFC), and temporal cortex (TE) all contribute to visual decision-making. Accumulating evidence suggests that vlPFC may play a central role in multiple cognitive operations, perhaps resembling domain-general regions of the human frontal lobe. We trained monkeys in a task call...

In the behaving monkey, complex neural dynamics in the prefrontal cortex contribute to context‐dependent decisions and attentional competition. We used demixed principal component analysis to track prefrontal activity dynamics in a cued target detection task. In this task, the animal combined identity of a visual object with a prior instruction cue...

Much animal learning is slow, with cumulative changes in behavior driven by reward prediction errors. When the abstract structure of a problem is known, however, both animals and formal learning models can rapidly attach new items to their roles within this structure, sometimes in a single trial. Frontal cortex is likely to play a key role in this...

Much animal learning is slow, with cumulative changes in behavior driven by reward prediction errors. When the abstract structure of a problem is known, however, both animals and formal learning models can rapidly attach new items to their roles within this structure, sometimes in a single trial. Frontal cortex is likely to play a key role in this...

Complex neural dynamics in the prefrontal cortex contribute to context-dependent decisions and attentional competition. To analyze these dynamics, we apply demixed principal component analysis to activity of a primate prefrontal cell sample recorded in a cued target detection task. The results track dynamics of cue and object coding, feeding into m...

Serial and parallel processing in visual search have been long debated in psychology, but the processing mechanism remains an open issue. Serial processing allows only one object at a time to be processed, whereas parallel processing assumes that various objects are processed simultaneously. Here, we present novel neural models for the two types of...

Complex cognition is dynamic, with each stage of a task requiring new cognitive processes appropriately linked to stimulus or other content. To investigate control over successive task stages, we recorded neural activity in lateral frontal and parietal cortex as monkeys carried out a complex object selection task, with each trial separated into pha...

Prefrontal neurons code many kinds of behaviourally relevant visual information. In behaving monkeys, we used a cued target detection task to address coding of objects, behavioural categories and spatial locations, examining the temporal evolution of neural activity across dorsal and ventral regions of the lateral prefrontal cortex (encompassing pa...

Prefrontal cortex has been proposed to show highly adaptive information coding, with neurons dynamically allocated to processing task-relevant information. To track this dynamic allocation in monkey prefrontal cortex, we used time-resolved measures of neural population activity in a simple case of competition between target (behaviorally critical)...

Cognitive flexibility is fundamental to adaptive intelligent behavior. Prefrontal cortex has long been associated with flexible cognitive function, but the neurophysiological principles that enable prefrontal cells to adapt their response properties according to context-dependent rules remain poorly understood. Here, we use time-resolved population...

It is widely supposed that the dorsolateral prefrontal cortex (DLPFC) is important in attentional control, but the neural mechanisms for this remain unknown. For visual displays, many models propose that separate display items or objects compete for attentional selection, with competitive weights determined by factors including task context and lon...

We have recently shown evidence for extensive temporally evolving opponent organization in monkey prefrontal cortex during a cued target detection task (Kusunoki et al., 2010). The largest set of neurons showed target-positive activity, with the strongest response to the target (T), intermediate activity for a nontarget that was a target on other t...

Behavioral significance is commonly coded by prefrontal neurons. The significance of a stimulus can be fixed through experience; in complex behavior, however, significance commonly changes with short-term context. To compare these cases, we trained monkeys in 2 versions of visual target detection. In both tasks, animals monitored a series of pictur...

The pFC plays a key role in flexible, context-specific decision making. One proposal [Machens, C. K., Romo, R., & Brody, C. D. Flexible control of mutual inhibition: A neural model of two-interval discrimination. Science, 307, 1121-1124, 2005] is that prefrontal cells may be dynamically organized into opponent coding circuits, with competitive grou...

The frontal lobes play a key role in sequential organization of behavior. Little is known, however, of the way frontal neurons code successive phases of a structured task plan. Using correlational analysis, we asked how a population of frontal cells represents the multiple events of a complex sequential task. Monkeys performed a conventional cue–ta...

Humans and monkeys mislocalize targets flashed around the time of a saccade. Here, we present data from three monkeys on a double-step task with a 100ms target duration. All three subjects mislocalized targets that were flashed around the time of the first saccade, in spite of long intersaccadic intervals. The error was consistently in the directio...

When objects are viewed in different illuminants, their color does not change or changes little in spite of significant changes in the wavelength composition of the light reflected from them. In previous studies, we have addressed the physiology underlying this color constancy by recording from cells in areas V1, V2, and V4 of the anesthetized monk...

The monkey's lateral intraparietal area (LIP) has been associated with attention and saccades. LIP neurons have visual on-responses to objects abruptly appearing in their receptive fields (RFs) and sustained activity preceding saccades to the RF. We studied the relationship between the on-responses and delay activity in LIP using a 'stable-array' t...

perisaccadic receptive field shifts in the lateral intraparietal area of the monkey. J Neurophysiol 89: 1519–1527, 2003. First published November 20, 2002; 10.1152/jn.00519.2002. Neurons in the lateral intraparietal area of the monkey (LIP) have visual receptive fields in retinotopic coordinates when studied in a fixation task. However, in the peri...

The brain cannot monitor or react towards the entire world at a given time. Instead, using the process of attention, it selects objects in the world for further analysis. Neuronal activity in the monkey intraparietal area has the properties appropriate for a neuronal substrate of attention: instead of all objects being represented in the parietal c...

Patients with parietal lesions may fail to adjust the orientation of their hand to that of a target object, or may make errors in judging the orientation of a bar. This suggests that the parietal cortex has a function in the discrimination of the orientation of objects. In this study we investigated the responses of axis-orientation-selective neuro...

Purpose: To specify the cues for the discrimination of orientation in depth in axis orientation selective (AOS) neurons.Method: We analyzed the responses of AOS neurons in the monkey caudal intraparietal sulcus (cIPS) region using binocular disparity stimuli generated by stereoscopic 3 D computer graphics.Result: Most AOS neurons (20/27) were sensi...

To specify the cues for the discrimination of orientation in depth in axis orientation selective (AOS) neurons. We analyzed the responses of AOS neurons in the monkey caudal intraparietal sulcus (cIPS) region using binocular disparity stimuli generated by stereoscopic 3 D computer graphics. Most AOS neurons (20/27) were sensitive to binocular dispa...

Neurons in the lateral intraparietal area (LIP) of the monkey represent salient stimuli. They respond to recently flashed stimuli that enter their receptive fields by virtue of saccades better than they respond to stable, behaviorally irrelevant stimuli brought into their receptive fields by saccades. They respond transiently to abrupt motion onset...

In the first part of this article, we review our neurophysiological studies of the hand-manipulation-related neurons in the anterior part of the lateral bank of the intraparietal sulcus (area AIP) . We describe the properties of visually responsive neurons in area AIP. Object-type visual-dominant neurons responded to the sight of objects and showed...

To generate coherent behaviour, the brain needs to attend selectively to the many objects that are present in the environment, but this poses several questions. How does the brain know which objects 'belong together'? How does the information from different senses get combined? How does this help to plan and carry out actions? The subject of attent...

The parietal cortex has long been thought to participate in the neural mechanisms underlying visual attention, spatial perception, and eye movements (Critchley 1953). This review will begin by describing the attentional and spatial aspects of saccadic performance in a patient with a frontoparietal deficit, and then show how single neuron activity i...

In our previous studies of hand manipulation task-related neurons, we found many neurons of the parietal association cortex which responded to the sight of three-dimensional (3D) objects. Most of the task-related neurons in the AIP area (the lateral bank of the anterior intraparietal sulcus) were visually responsive and half of them responded to ob...

When natural scenes are viewed, a multitude of objects that are stable in their environments are brought in and out of view by eye movements. The posterior parietal cortex is crucial for the analysis of space, visual attention and movement. Neurons in one of its subdivisions, the lateral intraparietal area (LIP), have visual responses to stimuli ap...

Recent neurophysiological studies in alert monkeys have revealed that the parietal association cortex plays a crucial role in depth perception and visually guided hand movement. The following five classes of parietal neurons covering various aspects of these functions have been identified: (1) depth-selective visual-fixation (VF) neurons of the inf...

Patients with parietal lesions may fail to adjust the orientation of the hand to that of the target object or may make errors in judging the orientation of the bar. This suggests that the parietal cortex functions to discriminate the orientation of objects. Therefore, we studied orientation selectivity of the visual neurons of the posterior parieta...

We studied the functional properties of rotation-sensitive (RS) neurons of the posterior parietal association cortex in detail. We classified 58 neurons as RS neurons on the basis of statistical analysis, to indicate that their responses to rotary movement were significantly greater (P < 0.01) than those to linear movement of the same stimulus. We...

The representation of perceptual space in the posterior parietal cortex can be divided into at least two categories: far space, beyond arm's reach, and peripersonal space, within arm's reach. These are encoded by different groups of neurons that are closely related to the control of gaze and the guidance of arm and hand movement, respectively.

We recorded neurons sensitive to depth movement from the inferior parietal lobule (area 7a) of alert behaving monkeys, and studied their response to changing sizes of retinal images and to changing binocular disparity. The size of the stimulus was changed by changing both the height and width of a slit in the same way, and the disparity change was...

In pigmented rabbits anesthetized with N2O (70%) and halothane (2-4%), Purkinje cells were extracellularly recorded in the flocculus. A large central visual field (60 degrees x 60 degrees) was used to optokinetically stimulate either the ipsi- or contralateral eye, and the direction and velocity selectivities of complex spike responses were examine...

In pigmented rabbits anesthetized with N2O (70%) and halothane (2-4%), Purkinje cells were extracellularly recorded in the nodulus. Large field (60 degrees x 60 degrees) optokinetic stimulation (OKS) with constant velocity was delivered to either the ipsi- or contralateral eye, and the direction and velocity selectivities of complex spike responses...

In order to describe precisely the fixed action patterns of salmon sexual behavior, we recorded the electromyographic (EMG) activities of trunk and jaw muscles from freely behaving male and female Him salmon (landlocked sockeye salmon,Oncorhynchus nerka). A series of action patterns (quivering and spawning act in males, digging, covering, prespawni...

Various patterns of sexual behavior were evoked in freely swimming hime salmon by electrical stimulation of specific loci in the telencephalon and the preoptic area (POA) using chronically implanted electrodes. Furthermore, co-ordinated sexual behavior corresponding to stages of the natural spawning sequence was elicited from some of these brain re...

In connection with indications of the magnetic field detection in migratory birds, the measurements of magnetic remanences were carried out in both the migratory birds (Rustig Bunting and Reed Bunting) and the non-migratory birds (Siberian Meadow Bunting and Tree Sparrow) by means of SQUID magnetometer. Regardless of whether the species was migrato...

described our recent studies of two groups of visual neurons of the posterior parietal association cortex in alert monkeys / one group contained neurons that were specifically sensitive to linear movement in depth, and the other contained neurons that were sensitive to depth rotation (PsycINFO Database Record (c) 2012 APA, all rights reserved)