Macaque monkeys

…to output similar hand trajectories as macaque monkeys in a manual interception task. In the network modules designed to model the dorsal premotor (PMd) and primary motor (M1) cortices, we observed that rotational neural dynamics during motor preparation transitioned into a subspace encoding hand positions during exec

…How similar is one macaque IT to another? This study investigates inter-individual variation in IT cortical representations by analyzing neural responses to 640 visual stimuli (100 ms presentation at 8 degrees) across eight macaque monkeys. We employed two complementary analytical approaches: a direct one-to-one neuron matching method to assess exact neural correspondence and a many-to-one linear regression framework to evaluate potential linear transformations between indivi

To date, most studies of neural representation have focused on how a single stimulus is encoded in the spiking activity of neurons. Consequently, little is known about how sensory neurons can preserve information from multiple stimuli – a problem given that many sensory neurons have relatively broad receptive fields. Multiplexing is a neural encoding theory that posits that neurons temporally switch between encoding various stimuli when more than one stimulus is present. To date, the strongest statistical evidence for this theory comes from spike counts measured over long time windows, leading

At the core of intelligence is the capacity to solve new problems. To do so, the brain must generate novel thoughts and behaviors in a goal-directed manner. This creative capacity has been hypothesized to depend on cognitive operations resembling symbolic grammars, generative models with discrete atomic objects (i.e., symbols) that use rule-based operations to generate newly composed representations. Whether and how symbolic grammars are implemented in neural substrates remains unknown. Here we develop an interdisciplinary approach to study the neural implementation of a grammar for action, ce

…in the primary visual cortex of macaque monkeys performing a task that reveals the animal's subjective sense of perceptual confidence. Specifical

The brain continuously receives vast amounts of information from the rest of the body and the environment, only a fraction of which can be consciously processed and stored in memory. It is believed that hippocampal sharp-wave ripples tag memories that are relevant and should be remembered (Yang et al 2024). However, this selection of relevant information must occur already during sensory processing to avoid overloading the system with irrelevant information. The hypothesis of this project is that short bursts of high gamma activity, referred to as cortical ripples to distinguish them from hipp

…electrocorticography (ECoG) in two macaque monkeys. Regions with similar functionality were identified by clustering the time-varying signal of electrodes

…Activated by Designer Drugs) in macaque monkeys. This approach is only now emerging for primates, and permits the targeted modulation of a specific neural pathway over a period of hours. We conducted two DREADD experiments to sp

The perirhinal and parahippocampal cortices are key components of the medial temporal lobe memory system and essential for the processing of spatial and declarative memory. In humans, major changes in declarative memory capacities occur within the first seven years of life, but until recently, the neurobiological substrates underlying these changes remained hypothetical. Previous studies have shown that distinct regions, layers and cells of the hippocampus and entorhinal cortex exhibit different profiles of structural and molecular development during early postnatal life. Accordingly, the diff

Flexible routing of visual input signals has been linked to changing patterns of synchrony between gamma rhythms of distant neural groups. It has been proposed that attention increases distant gamma-band synchrony by increasing the gamma frequency of the sender group processing the attended stimulus. This stimulus is subsequently preferentially processed. However, the frequency of gamma activity fluctuates over time, varies between areas, and depends on stimulus characteristics, which may complicate entrainment between oscillators. Here, we investigate the relationship between the frequency of

…range of 70-150 Hz in V1 and V4 of two macaque monkeys implanted with 16 Utah electrode arrays each [1]. The activity was recorded during resting state with occasional periods of drowsing. We observed prominent events with hi

…and subcortical brain areas of macaque monkeys. We applied Fourier-based waveform analysis to LFP oscillations and syst

…of the hippocampal formation in macaque monkeys

…activity in prefrontal cortex of macaque monkeys trained to flexibly report categorical judgments of ambiguous visual stimuli. The subjects judged whether a visual stimulus presented near the central visual field was orient

…of neurons in the prefrontal cortex of macaque monkeys memorizing and then reproducing a sequence of locations after a delay. We discovered a regular geometrical organization: The high-dimensional neural state space during the delay could be decomposed into a sum of low-dimensional subspaces, each storing the spatial location at a given ordinal rank, which could be generalized to novel sequences and explain mo

The attenuation of neural responses to repeated stimuli (response attenuation) is often attributed to either adaptation or predictive suppression. While the two mechanisms differ dramatically in their theoretical underpinnings and computational complexity, they have been difficult to separate experimentally, because they make rather similar prediction in many commonly used paradigms. To that aim we developed a new experimental paradigm that leverages the time-course of response attenuation to arbitrate between the two theories. If response attenuation is mediated by adaptation, we expect the s

…To address this question, we trained macaque monkeys to view displays consisting o

…and neural measurements from 2 infant macaque monkeys at the ages of 6 and 12 mo, using texture stimuli that were parametrically varied in naturalness. We used a novel visual search task to efficiently measure behavioral naturalness sensitivity. W

…for metacognition on memory in macaque monkeys. In reality, awareness of ignorance is essential not only for the retrospection of the past but also for the exploration of novel unfamiliar environments for the future. However, this proactive feature of

Technological advances have increased the availability of recordings from large populations of neurons across multiple brain areas. Coupling these recordings with dimensionality reduction techniques, recent work has led to new proposals for how populations of neurons can send and receive signals selectively and flexibly. Advancement of these proposals depends, however, on untangling the bidirectional, parallel communication between neuronal populations. Because our current data analytic tools struggle to achieve this task, we have recently validated and presented a novel dimensionality reducti