Soo Hyun Park

How the brain fluidly orchestrates visual behavior is a central question in cognitive neuroscience. Researchers studying neural responses in humans and nonhuman primates have mapped out visual response profiles and cognitive modulation in a large number of brain areas, most often using pared down stimuli and highly controlled behavioral paradigms. The historical emphasis on reductionism has placed most studies at one pole of an inherent trade-off between strictly controlled experimental variable

During normal vision, our eyes provide the brain with a continuous stream of useful information about the world. How visually specialized areas of the cortex, such as face-selective patches, operate under natural modes of behavior is poorly understood. Here we report that, during the free viewing of movies, cohorts of face-selective neurons in the macaque cortex fractionate into distributed and parallel subnetworks that carry distinct information. We classified neurons into functional groups on

The brain helps us survive by forming internal representations of the external world1,2. Excitatory cortical neurons are often precisely tuned to specific external stimuli3,4. However, inhibitory neurons, such as parvalbumin-positive (PV) interneurons, are generally less selective5. PV interneurons differ from excitatory neurons in their neurotransmitter receptor subtypes, including AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid) receptors (AMPARs)6,7. Excitatory neurons express cal

A focal stimulus triggers neural activity that spreads to cortical regions far beyond the stimulation site, creating a so-called "cortical point spread" (CPS). Animal studies found that V1 neurons possess lateral connections with neighboring neurons that prefer similar orientations and to neurons representing visuotopic regions that are constrained by their preferred orientation axis. Although various roles in visual processing are proposed for this anatomical anisotropy of lateral connections,

The brain is a highly organized, dynamic system whose network architecture is often assessed through resting functional magnetic resonance imaging (fMRI) functional connectivity. The functional interactions between brain areas, including those observed during rest, are assumed to stem from the collective influence of action potentials carried by long-range neural projections. However, the contribution of individual neurons to brain-wide functional connectivity has not been systematically assesse

Ionizing radiation suppresses neurogenesis in the mammalian brain. This in vitro study compared the detrimental effect of acute gamma-irradiation on immature hippocampal cells with mature cells. Both rat immature (0.5 day in vitro (DIV)) and mature hippocampal cells (14 DIV) were irradiated with 0-4 Gy gamma-rays. Cell viability was analyzed by using a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay. DNA fragmentation study was performed by extracting intracellular DNA.

Abstract During normal vision, our eyes provide the brain with a continuous stream of useful information about the world. How visually specialized areas of the cortex, such as face-selective patches, operate under natural modes of behavior is poorly understood. Here we report that, during the free viewing of videos, cohorts of face-selective neurons in the macaque cortex fractionate into distributed and parallel subnetworks that carry distinct information. We classified neurons into functional g

The brain helps us survive by forming internal representations of the external world 1,2 . Excitatory cortical neurons are often precisely tuned to specific external stimuli 3,4 . However, inhibitory neurons, such as parvalbumin-positive (PV) interneurons, are generally less selective 5 . PV interneurons differ from excitatory cells in their neurotransmitter receptor subtypes, including AMPA receptors 6,7 . While excitatory neurons express calcium-impermeable AMPA receptors containing the GluA2

A visual stimulus not only evokes spiking activity in neurons whose receptive fields (RFs) are overlapped with the stimulus but also promotes subthreshold activity over an extended cortical region outside the directly stimulated region, known as cortical point spread (PS). Optical imaging studies on animal visual cortex demonstrated that PS is biased to cortical sites whose orientation preferences are similar to stimulus orientation (“co-orientation anisotropy”). Anatomical studies reported also

<b>1. correlationMatrix_neuron_fROI.mat</b><br>Contains the matrix of correlation (166 x 37) between 166 face-selective neurons recorded from different face patches and hemodynamic responses from 37 functional Regions of Interest (ROIs). fROIs are defined across visual cortex, including regions from occipital, temporal, parietal, and frontal lobes. Information of neurons and fROIs are provided in separate file (info.mat).<br><br><b>2. info.mat</b><br>Contains the information of the functional Re

<b>1. correlationMatrix_neuron_fROI.mat</b><br>Contains the matrix of correlation (166 x 37) between 166 face-selective neurons recorded from different face patches and hemodynamic responses from 37 functional Regions of Interest (ROIs). fROIs are defined across visual cortex, including regions from occipital, temporal, parietal, and frontal lobes. Information of neurons and fROIs are provided in separate file (info.mat).<br><br><b>2. info.mat</b><br>Contains the information of the functional Re

Abstract We present a novel approach for endoscopic calcium imaging in the marmoset extrastriate visual cortex, combining a chronically implanted microprism lens with an integrated injection cannula. This method achieved stable, longitudinal imaging of visually responsive GCaMP-expressing neurons over multiple weeks. Using a head-mounted miniscope in two subjects, we repeatedly presented naturalistic visual stimuli and longitudinally tracked the activity of more than one hundred neurons across s

Emotional labor, characterized by a dysfunctional type of emotional regulation called surface acting, has detrimental psychological consequences on employees, including depression and social anxiety. Because such disorders exhibit psychological characteristics manifested through brain activation, previous studies have succeeded in distinguishing individuals with depression and social anxiety from healthy controls using their functional connectivity characteristics. However, it has not been estab