1
|
Suematsu N, Vazquez AL, Kozai TDY. Activation and depression of neural and hemodynamic responses induced by the intracortical microstimulation and visual stimulation in the mouse visual cortex. J Neural Eng 2024; 21:026033. [PMID: 38537268 PMCID: PMC11002944 DOI: 10.1088/1741-2552/ad3853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 02/28/2024] [Accepted: 03/27/2024] [Indexed: 04/09/2024]
Abstract
Objective. Intracortical microstimulation (ICMS) can be an effective method for restoring sensory perception in contemporary brain-machine interfaces. However, the mechanisms underlying better control of neuronal responses remain poorly understood, as well as the relationship between neuronal activity and other concomitant phenomena occurring around the stimulation site.Approach. Different microstimulation frequencies were investigatedin vivoon Thy1-GCaMP6s mice using widefield and two-photon imaging to evaluate the evoked excitatory neural responses across multiple spatial scales as well as the induced hemodynamic responses. Specifically, we quantified stimulation-induced neuronal activation and depression in the mouse visual cortex and measured hemodynamic oxyhemoglobin and deoxyhemoglobin signals using mesoscopic-scale widefield imaging.Main results. Our calcium imaging findings revealed a preference for lower-frequency stimulation in driving stronger neuronal activation. A depressive response following the neural activation preferred a slightly higher frequency stimulation compared to the activation. Hemodynamic signals exhibited a comparable spatial spread to neural calcium signals. Oxyhemoglobin concentration around the stimulation site remained elevated during the post-activation (depression) period. Somatic and neuropil calcium responses measured by two-photon microscopy showed similar dependence on stimulation parameters, although the magnitudes measured in soma was greater than in neuropil. Furthermore, higher-frequency stimulation induced a more pronounced activation in soma compared to neuropil, while depression was predominantly induced in soma irrespective of stimulation frequencies.Significance. These results suggest that the mechanism underlying depression differs from activation, requiring ample oxygen supply, and affecting neurons. Our findings provide a novel understanding of evoked excitatory neuronal activity induced by ICMS and offer insights into neuro-devices that utilize both activation and depression phenomena to achieve desired neural responses.
Collapse
Affiliation(s)
- Naofumi Suematsu
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Alberto L Vazquez
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States of America
- Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, Pittsburgh, PA, United States of America
- Department of Radiology, University of Pittsburgh, Pittsburgh, PA, United States of America
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Takashi D Y Kozai
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States of America
- Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, Pittsburgh, PA, United States of America
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States of America
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
- NeuroTech Center, University of Pittsburgh Brain Institute, Pittsburgh, PA, United States of America
| |
Collapse
|
2
|
Suematsu N, Vazquez AL, Kozai TD. Activation and depression of neural and hemodynamic responses induced by the intracortical microstimulation and visual stimulation in the mouse visual cortex. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.01.573814. [PMID: 38260671 PMCID: PMC10802282 DOI: 10.1101/2024.01.01.573814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Objective . Intracortical microstimulation can be an effective method for restoring sensory perception in contemporary brain-machine interfaces. However, the mechanisms underlying better control of neuronal responses remain poorly understood, as well as the relationship between neuronal activity and other concomitant phenomena occurring around the stimulation site. Approach . Different microstimulation frequencies were investigated in vivo on Thy1-GCaMP6s mice using widefield and two-photon imaging to evaluate the evoked excitatory neural responses across multiple spatial scales as well as the induced hemodynamic responses. Specifically, we quantified stimulation-induced neuronal activation and depression in the mouse visual cortex and measured hemodynamic oxyhemoglobin and deoxyhemoglobin signals using mesoscopic-scale widefield imaging. Main results . Our calcium imaging findings revealed a preference for lower-frequency stimulation in driving stronger neuronal activation. A depressive response following the neural activation preferred a slightly higher frequency stimulation compared to the activation. Hemodynamic signals exhibited a comparable spatial spread to neural calcium signals. Oxyhemoglobin concentration around the stimulation site remained elevated during the post-activation (depression) period. Somatic and neuropil calcium responses measured by two-photon microscopy showed similar dependence on stimulation parameters, although the magnitudes measured in soma was greater than in neuropil. Furthermore, higher-frequency stimulation induced a more pronounced activation in soma compared to neuropil, while depression was predominantly induced in soma irrespective of stimulation frequencies. Significance . These results suggest that the mechanism underlying depression differs from activation, requiring ample oxygen supply, and affecting neurons. Our findings provide a novel understanding of evoked excitatory neuronal activity induced by intracortical microstimulation and offer insights into neuro-devices that utilize both activation and depression phenomena to achieve desired neural responses.
Collapse
|
3
|
Liu X, Robinson PA. Analytic Model for Feature Maps in the Primary Visual Cortex. Front Comput Neurosci 2022; 16:659316. [PMID: 35185503 PMCID: PMC8854373 DOI: 10.3389/fncom.2022.659316] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 01/05/2022] [Indexed: 11/29/2022] Open
Abstract
A compact analytic model is proposed to describe the combined orientation preference (OP) and ocular dominance (OD) features of simple cells and their mutual constraints on the spatial layout of the combined OP-OD map in the primary visual cortex (V1). This model consists of three parts: (i) an anisotropic Laplacian (AL) operator that represents the local neural sensitivity to the orientation of visual inputs; and (ii) obtain a receptive field (RF) operator that models the anisotropic spatial projection from nearby neurons to a given V1 cell over scales of a few tenths of a millimeter and combines with the AL operator to give an overall OP operator; and (iii) a map that describes how the parameters of these operators vary approximately periodically across V1. The parameters of the proposed model maximize the neural response at a given OP with an OP tuning curve fitted to experimental results. It is found that the anisotropy of the AL operator does not significantly affect OP selectivity, which is dominated by the RF anisotropy, consistent with Hubel and Wiesel's original conclusions that orientation tuning width of V1 simple cell is inversely related to the elongation of its RF. A simplified and idealized OP-OD map is then constructed to describe the approximately periodic local OP-OD structure of V1 in a compact form. It is shown explicitly that the OP map can be approximated by retaining its dominant spatial Fourier coefficients, which are shown to suffice to reconstruct its basic spatial structure. Moreover, this representation is a suitable form to analyze observed OP maps compactly and to be used in neural field theory (NFT) for analyzing activity modulated by the OP-OD structure of V1. Application to independently simulated V1 OP structure shows that observed irregularities in the map correspond to a spread of dominant coefficients in a circle in Fourier space. In addition, there is a strong bias toward two perpendicular directions when only a small patch of local map is included. The bias is decreased as the amount of V1 included in the Fourier transform is increased.
Collapse
Affiliation(s)
- Xiaochen Liu
- School of Physics, The University of Sydney, Sydney, NSW, Australia
- Center for Integrative Brain Function, The University of Sydney, Sydney, NSW, Australia
- *Correspondence: Xiaochen Liu
| | - Peter A. Robinson
- School of Physics, The University of Sydney, Sydney, NSW, Australia
- Center for Integrative Brain Function, The University of Sydney, Sydney, NSW, Australia
| |
Collapse
|
4
|
Kimura R, Yoshimura Y. The contribution of low contrast-preferring neurons to information representation in the primary visual cortex after learning. SCIENCE ADVANCES 2021; 7:eabj9976. [PMID: 34826242 PMCID: PMC8626071 DOI: 10.1126/sciadv.abj9976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 10/07/2021] [Indexed: 06/13/2023]
Abstract
Animals exhibit improved perception of lower-contrast visual objects after training. We explored this neuronal mechanism using multiple single-unit recordings from deep layers of the primary visual cortex (V1) of trained rats during orientation discrimination. We found that the firing rates of a subset of neurons increased by reducing luminance contrast, being at least above basal activities at low contrast. These low contrast–preferring neurons were rare during passive viewing without training or anesthesia after training. They fired more frequently in correct-choice than incorrect-choice trials. At single-neuron and population levels, they efficiently represented low-contrast orientations. Following training, in addition to generally enhanced excitation, the phase synchronization of spikes to beta oscillations at high contrast was stronger in putative inhibitory than excitatory neurons. The change in excitation-inhibition balance might contribute to low-contrast preference. Thus, low-contrast preference in V1 activity is strengthened in an experience-dependent manner, which may contribute to low-contrast visual discrimination.
Collapse
Affiliation(s)
- Rie Kimura
- Division of Visual Information Processing, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Japan
- Department of Physiological Sciences, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Japan
| | - Yumiko Yoshimura
- Division of Visual Information Processing, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Japan
- Department of Physiological Sciences, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Japan
| |
Collapse
|
5
|
Sun SH, Almasi A, Yunzab M, Zehra S, Hicks DG, Kameneva T, Ibbotson MR, Meffin H. Analysis of extracellular spike waveforms and associated receptive fields of neurons in cat primary visual cortex. J Physiol 2021; 599:2211-2238. [PMID: 33501669 DOI: 10.1113/jp280844] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 01/12/2021] [Indexed: 12/11/2022] Open
Abstract
KEY POINTS Extracellular spikes recorded in the visual cortex (Area 17/18, V1) are commonly classified into either regular-spiking (RS) or fast-spiking (FS). Using multi-electrode arrays positioned in cat V1 and a broadband stimulus, we show that there is also a distinct class with positive-spiking (PS) waveforms. PS units were associated mainly with non-oriented receptive fields while RS and FS units had orientation-selective receptive fields. We suggest that PS units are recordings of axons originating from the thalamus. This conclusion was reinforced by our finding that we could record PS units after cortical silencing, but not record RS and FS units. The importance of our findings is that we were able to correlate spike shapes with receptive field characteristics with high precision using multi-electrode extracellular recording techniques. This allows considerable increases in the amount of information that can be extracted from future cortical experiments. ABSTRACT Extracellular spike waveforms from recordings in the visual cortex have been classified into either regular-spiking (RS) or fast-spiking (FS) units. While both these types of spike waveforms are negative-dominant, we show that there are also distinct classes of spike waveforms in visual Area 17/18 (V1) of anaesthetised cats with positive-dominant waveforms, which are not regularly reported. The spatial receptive fields (RFs) of these different spike waveform types were estimated, which objectively revealed the existence of oriented and non-oriented RFs. We found that units with positive-dominant spikes, which have been associated with recordings from axons in the literature, had mostly non-oriented RFs (84%), which are similar to the centre-surround RFs observed in the dorsal lateral geniculate nucleus (dLGN). Thus, we hypothesise that these positive-dominant waveforms may be recordings from dLGN afferents. We recorded from V1 before and after the application of muscimol (a cortical silencer) and found that the positive-dominant spikes (PS) remained while the RS and FS cells did not. We also noted that the PS units had spiking characteristics normally associated with dLGN units (i.e. higher response spike rates, lower response latencies and higher proportion of burst spikes). Our findings show quantitatively that it is possible to correlate the RF properties of cortical neurons with particular spike waveforms. This has implications for how extracellular recordings should be interpreted and complex experiments can now be contemplated that would have been very challenging previously, such as assessing the feedforward connectivity between brain areas in the same location of cortical tissue.
Collapse
Affiliation(s)
- Shi H Sun
- National Vision Research Institute, Australian College of Optometry, Carlton, Victoria, 3053, Australia
| | - Ali Almasi
- National Vision Research Institute, Australian College of Optometry, Carlton, Victoria, 3053, Australia
| | - Molis Yunzab
- National Vision Research Institute, Australian College of Optometry, Carlton, Victoria, 3053, Australia
| | - Syeda Zehra
- Faculty of Science, Engineering and Technology, Swinburne University, Hawthorn, Victoria, 3122, Australia.,Department of Biomedical Engineering, University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Damien G Hicks
- Faculty of Science, Engineering and Technology, Swinburne University, Hawthorn, Victoria, 3122, Australia.,Optical Sciences Centre, Swinburne University, Hawthorn, Victoria, 3122, Australia
| | - Tatiana Kameneva
- Faculty of Science, Engineering and Technology, Swinburne University, Hawthorn, Victoria, 3122, Australia.,Department of Biomedical Engineering, University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Michael R Ibbotson
- National Vision Research Institute, Australian College of Optometry, Carlton, Victoria, 3053, Australia.,Department of Optometry and Vision Sciences, University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Hamish Meffin
- National Vision Research Institute, Australian College of Optometry, Carlton, Victoria, 3053, Australia.,Department of Biomedical Engineering, University of Melbourne, Parkville, Victoria, 3010, Australia
| |
Collapse
|
6
|
Experience-Dependent Development of Feature-Selective Synchronization in the Primary Visual Cortex. J Neurosci 2018; 38:7852-7869. [PMID: 30064994 DOI: 10.1523/jneurosci.0027-18.2018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 07/24/2018] [Accepted: 07/24/2018] [Indexed: 11/21/2022] Open
Abstract
Early visual experience is essential for the maturation of visual functions in which the primary visual cortex plays crucial roles. The extraction of visual features based on response selectivity of individual neurons, a fundamental process in the cortex, is basically established by eye opening in rodents, suggesting that visual experience is required for the development of neural functions other than feature extraction. Here, we show that synchronized firing, which is important for visual information processing, occurs selectively in adjacent neurons sharing similar orientation or spatial frequency preferences in layers 2-4 (upper layer) of rat visual cortex. This feature-selective spike synchrony was rudimentary when the eyes opened and became prominent during the first few weeks after eye opening only in the presence of pattern vision. In contrast, synchronization in layers 5-6 (lower layer) was almost independent of orientation similarity and more weakly dependent on spatial frequency similarity compared with upper layer synchrony. Lower layer synchronization was strengthened during development after eye opening independently of visual experience as a whole. However, the feature selectivity of synchronization was regulated by visual inputs, whereas the inputs without contours were sufficient for this regulation. Therefore, we speculate that feature-selective synchronization in the upper layer may convey detailed information on visual objects to the higher-order cortex, whereas weakly feature-selective synchronization in the lower layer may covey rather rough visual information to the subcortical areas or higher-order cortex. A major role of visual experience may be to establish the specific neural circuits underlying highly feature-selective synchronization.SIGNIFICANCE STATEMENT The neuronal mechanisms underlying experience-dependent improvement of visual functions still remain unresolved. In this study, we investigated whether early visual experience contributes to the development of synchronized neural firing in the primary visual cortex, which plays important roles in visual information processing. We found that synchronized firing depends more remarkably on the similarity of preferred visual stimuli in the upper than lower layer neurons. Pattern vision during development was required for the establishment of spike synchrony in the upper but not the lower layer. These findings provide a new view regarding the role of sensory experience in the functional development of the cortex and the differences in the modes of information processing in the upper and lower cortical layers.
Collapse
|
7
|
Li H, Fang Q, Ge Y, Li Z, Meng J, Zhu J, Yu H. Relationship between the Dynamics of Orientation Tuning and Spatiotemporal Receptive Field Structures of Cat LGN Neurons. Neuroscience 2018; 377:26-39. [PMID: 29481999 DOI: 10.1016/j.neuroscience.2018.02.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 02/01/2018] [Accepted: 02/15/2018] [Indexed: 10/18/2022]
Abstract
Simple cells in the cat primary visual cortex usually have elongated receptive fields (RFs), and their orientation selectivity can be largely predicted by their RFs. As to the relay cells in cats' lateral geniculate nucleus (LGN), they also have weak but significant orientation bias (OB). It is thus of interest to investigate the fine spatiotemporal receptive field (STRF) properties in LGN, compare them with the dynamics of orientation tuning, and examine the dynamic relationship between STRF and orientation sensitivity in LGN. We mapped the STRFs of the LGN neurons in cats with white noise and characterized the dynamics of the orientation tuning by flashing gratings. We found that most of the LGN neurons showed elongated RFs and that the elongation axes were consistent with the preferred orientations. STRFs and the dynamics of orientation tuning were closely correlated temporally: the elongation of RFs and OB emerged, peaked and decayed at the same pace, with unchanged elongation axis of RF and preferred orientation but consistently changing aspect ratio of RF and OB strength across time. Importantly, the above consistency between RF and orientation tuning was not influenced by the ablation of the primary visual cortex. Furthermore, biased orientation tuning emerged 20-30 ms earlier than those in the primary visual cortex. These data demonstrated that similar to the primary visual cortex, the orientation sensitivity was closely reflected by the RF properties in LGN. However, the elongated RF and OB in LGN did not originate from the primary visual cortex feedback.
Collapse
Affiliation(s)
- Hongjian Li
- Vision Research Laboratory, School of Life Sciences, The State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200433, China
| | - Qi Fang
- Vision Research Laboratory, School of Life Sciences, The State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200433, China
| | - Yijun Ge
- Vision Research Laboratory, School of Life Sciences, The State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200433, China
| | - Zhong Li
- Vision Research Laboratory, School of Life Sciences, The State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200433, China
| | - Jianjun Meng
- Vision Research Laboratory, School of Life Sciences, The State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200433, China
| | - Jianbing Zhu
- Vision Research Laboratory, School of Life Sciences, The State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200433, China
| | - Hongbo Yu
- Vision Research Laboratory, School of Life Sciences, The State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200433, China.
| |
Collapse
|
8
|
Osaki H, Naito T, Soma S, Sato H. Receptive field properties of cat perigeniculate neurons correlate with excitatory and inhibitory connectivity to LGN relay neurons. Neurosci Res 2017; 132:26-36. [PMID: 28916470 DOI: 10.1016/j.neures.2017.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 08/21/2017] [Accepted: 09/06/2017] [Indexed: 11/19/2022]
Abstract
The cat perigeniculate nucleus (PGN) is a visual sector of the thalamic reticular nucleus that consists of GABAergic neurons. It receives excitatory axon-collateral input from relay neurons of the dorsal lateral geniculate nucleus (LGN) to which it provides inhibitory input. Thus, it is usually argued that the PGN works as feedback inhibition to the LGN. At the single neuron level, however, this circuit can also provide lateral inhibition. Which inhibition dominates in the visual circuit of the thalamus has yet to be well characterized. In this study, we conducted cross-correlation analysis of single spike trains simultaneously recorded from PGN and LGN neurons in anesthetized cats. For 12 pairs of functionally connected PGN and LGN neurons with overlapped receptive fields (RF), we quantitatively compared RF properties including the spatial frequency (SF) and temporal frequency (TF) tunings of each neuron. We found the SF and TF tunings of PGN neurons and LGN neurons were similar when there was only excitatory input from the LGN neuron to the PGN neuron, but different when the PGN neuron returned inhibitory inputs back, suggesting the circuit between PGN and LGN neurons works as lateral inhibition for these properties.
Collapse
Affiliation(s)
- Hironobu Osaki
- Graduate School of Medicine, Osaka University, Osaka 560-0043, Japan.
| | - Tomoyuki Naito
- Graduate School of Medicine, Osaka University, Osaka 560-0043, Japan
| | - Shogo Soma
- Graduate School of Frontier Biosciences, Osaka University, Osaka 560-0043, Japan
| | - Hiromichi Sato
- Graduate School of Medicine, Osaka University, Osaka 560-0043, Japan; Graduate School of Frontier Biosciences, Osaka University, Osaka 560-0043, Japan
| |
Collapse
|
9
|
Towards building a more complex view of the lateral geniculate nucleus: Recent advances in understanding its role. Prog Neurobiol 2017. [DOI: 10.1016/j.pneurobio.2017.06.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
10
|
Poltoratski S, Ling S, McCormack D, Tong F. Characterizing the effects of feature salience and top-down attention in the early visual system. J Neurophysiol 2017; 118:564-573. [PMID: 28381491 PMCID: PMC5511869 DOI: 10.1152/jn.00924.2016] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 03/31/2017] [Accepted: 04/01/2017] [Indexed: 11/22/2022] Open
Abstract
The visual system employs a sophisticated balance of attentional mechanisms: salient stimuli are prioritized for visual processing, yet observers can also ignore such stimuli when their goals require directing attention elsewhere. A powerful determinant of visual salience is local feature contrast: if a local region differs from its immediate surround along one or more feature dimensions, it will appear more salient. We used high-resolution functional MRI (fMRI) at 7T to characterize the modulatory effects of bottom-up salience and top-down voluntary attention within multiple sites along the early visual pathway, including visual areas V1-V4 and the lateral geniculate nucleus (LGN). Observers viewed arrays of spatially distributed gratings, where one of the gratings immediately to the left or right of fixation differed from all other items in orientation or motion direction, making it salient. To investigate the effects of directed attention, observers were cued to attend to the grating to the left or right of fixation, which was either salient or nonsalient. Results revealed reliable additive effects of top-down attention and stimulus-driven salience throughout visual areas V1-hV4. In comparison, the LGN exhibited significant attentional enhancement but was not reliably modulated by orientation- or motion-defined salience. Our findings indicate that top-down effects of spatial attention can influence visual processing at the earliest possible site along the visual pathway, including the LGN, whereas the processing of orientation- and motion-driven salience primarily involves feature-selective interactions that take place in early cortical visual areas.NEW & NOTEWORTHY While spatial attention allows for specific, goal-driven enhancement of stimuli, salient items outside of the current focus of attention must also be prioritized. We used 7T fMRI to compare salience and spatial attentional enhancement along the early visual hierarchy. We report additive effects of attention and bottom-up salience in early visual areas, suggesting that salience enhancement is not contingent on the observer's attentional state.
Collapse
Affiliation(s)
- Sonia Poltoratski
- Vanderbilt Vision Research Center, Psychology Department, Vanderbilt University, Nashville, Tennessee; and
| | - Sam Ling
- Department of Psychological & Brain Sciences, Center for Computational Neuroscience and Neural Technology, Boston University, Boston, Massachusetts
| | - Devin McCormack
- Vanderbilt Vision Research Center, Psychology Department, Vanderbilt University, Nashville, Tennessee; and
| | - Frank Tong
- Vanderbilt Vision Research Center, Psychology Department, Vanderbilt University, Nashville, Tennessee; and
| |
Collapse
|
11
|
Intracellular, In Vivo, Dynamics of Thalamocortical Synapses in Visual Cortex. J Neurosci 2017; 37:5250-5262. [PMID: 28438969 DOI: 10.1523/jneurosci.3370-16.2017] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 02/24/2017] [Accepted: 04/01/2017] [Indexed: 11/21/2022] Open
Abstract
Seminal studies of the thalamocortical circuit in the visual system of the cat have been central to our understanding of sensory encoding. However, thalamocortical synaptic properties remain poorly understood. We used paired recordings, in the lateral geniculate nucleus (LGN) and primary visual cortex (V1), to provide the first in vivo characterization of sensory-driven thalamocortical potentials in V1. The amplitudes of EPSPs we characterized were smaller than those previously reported in vitro Consistent with prior findings, connected LGN-V1 pairs were only found when their receptive fields (RFs) overlapped, and the probability of connection increased steeply with degree of RF overlap and response similarity. However, surprisingly, we found no relationship between EPSP amplitudes and the similarity of RFs or responses, suggesting different connectivity models for intracortical and thalamocortical circuits. Putative excitatory regular-spiking (RS) and inhibitory fast-spiking (FS) V1 cells had similar EPSP characteristics, showing that in the visual system, feedforward excitation and inhibition are driven with equal strength by the thalamus. Similar to observations in the somatosensory cortex, FS V1 cells received less specific input from LGN. Finally, orientation tuning in V1 was not inherited from single presynaptic LGN cells, suggesting that it must emerge exclusively from the combined input of all presynaptic LGN cells. Our results help to decipher early visual encoding circuits and have immediate utility in providing physiological constraints to computational models of the visual system.SIGNIFICANCE STATEMENT To understand how the brain encodes the visual environment, we must understand the transfer of visual signals between various regions of the brain. Therefore, understanding synaptic dynamics is critical to our understanding of sensory encoding. This study provides the first characterization of visually evoked synaptic potentials between the visual thalamus and visual cortex in an intact animal. To record these potentials, we simultaneously recorded the extracellular potential of presynaptic thalamic cells and the intracellular potential of postsynaptic cortical cells in input layers of primary visual cortex. Our characterization of synaptic potentials in vivo disagreed with prior findings in vitro This study will increase our understanding of thalamocortical circuits and will improve computational models of visual encoding.
Collapse
|
12
|
Yakimova EG, Chizhov AV. Experimental and Modeling Studies of Orientational Sensitivity of Neurons in the Lateral Geniculate Nucleus. ACTA ACUST UNITED AC 2015. [DOI: 10.1007/s11055-015-0097-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
13
|
Soma S, Suematsu N, Shimegi S. Efficient training protocol for rapid learning of the two-alternative forced-choice visual stimulus detection task. Physiol Rep 2014; 2:2/7/e12060. [PMID: 24994895 PMCID: PMC4187546 DOI: 10.14814/phy2.12060] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The potential of genetically engineered rodent models has accelerated demand for training procedures of behavioral tasks. Such training is generally time consuming and often shows large variability in learning speed between animals. To overcome these problems, we developed an efficient and stable training system for the two-alternative forced-choice (2AFC) visual stimulus detection task for freely behaving rodents. To facilitate the task learning, we introduced a spout-lever as the operandum and a three-step training program with four ingenuities: (1) a salient stimulus to draw passive attention, (2) a reward-guaranteed trial to keep motivation, (3) a behavior-corrective trial, and (4) switching from a reward-guaranteed trial to a nonguaranteed one to correct behavioral patterns. Our new training system realizes 1-week completion of the whole learning process, during which all rats were able to learn effortlessly the association between (1) lever-manipulation and reward and (2) visual stimulus and reward in a step-by-step manner. Thus, our new system provides an effective and stable training method for the 2AFC visual stimulus detection task. This method should help accelerate the move toward research bridging the visual functions measured in behavioral tasks and the contributing specific neurons/networks that are genetically manipulated or optically controlled.
Collapse
Affiliation(s)
- Shogo Soma
- Laboratory of Cognitive and Behavioral Neuroscience, Graduate School of Medicine, Osaka University, Toyonaka, Osaka, Japan
| | - Naofumi Suematsu
- Laboratory of Cognitive and Behavioral Neuroscience, Graduate School of Medicine, Osaka University, Toyonaka, Osaka, Japan
| | - Satoshi Shimegi
- Laboratory of Cognitive and Behavioral Neuroscience, Graduate School of Medicine, Osaka University, Toyonaka, Osaka, Japan
| |
Collapse
|
14
|
Cattan S, Bachatene L, Bharmauria V, Jeyabalaratnam J, Milleret C, Molotchnikoff S. Comparative analysis of orientation maps in areas 17 and 18 of the cat primary visual cortex following adaptation. Eur J Neurosci 2014; 40:2554-63. [DOI: 10.1111/ejn.12616] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 04/07/2014] [Accepted: 04/10/2014] [Indexed: 11/28/2022]
Affiliation(s)
- Sarah Cattan
- Département de sciences biologiques; Université de Montréal; Pavillon Marie-Victorin, C.P. 6128, succ. Centre-ville Montréal QC H3C 3J7 Canada
| | - Lyes Bachatene
- Département de sciences biologiques; Université de Montréal; Pavillon Marie-Victorin, C.P. 6128, succ. Centre-ville Montréal QC H3C 3J7 Canada
| | - Vishal Bharmauria
- Département de sciences biologiques; Université de Montréal; Pavillon Marie-Victorin, C.P. 6128, succ. Centre-ville Montréal QC H3C 3J7 Canada
| | - Jeyadarshan Jeyabalaratnam
- Département de sciences biologiques; Université de Montréal; Pavillon Marie-Victorin, C.P. 6128, succ. Centre-ville Montréal QC H3C 3J7 Canada
| | - Chantal Milleret
- Neural Bases of Spatial Memory and Navigation; CIRB - Collège de France (CNRS UMR 7241, INSERM U1050, UPMC ED 158, MEMOLIFE PSL); Paris France
| | - Stéphane Molotchnikoff
- Département de sciences biologiques; Université de Montréal; Pavillon Marie-Victorin, C.P. 6128, succ. Centre-ville Montréal QC H3C 3J7 Canada
| |
Collapse
|
15
|
Suematsu N, Naito T, Miyoshi T, Sawai H, Sato H. Spatiotemporal receptive field structures in retinogeniculate connections of cat. Front Syst Neurosci 2013; 7:103. [PMID: 24367299 PMCID: PMC3856685 DOI: 10.3389/fnsys.2013.00103] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Accepted: 11/18/2013] [Indexed: 11/15/2022] Open
Abstract
The spatial structure of the receptive field (RF) of cat lateral geniculate nucleus (LGN) neurons is significantly elliptical, which may provide a basis for the orientation tuning of LGN neurons, especially at high spatial frequency stimuli. However, the input mechanisms generating this elliptical RF structure are poorly defined. We therefore compared the spatiotemporal RF structures of pairs of retinal ganglion cells (RGCs) and LGN neurons that form monosynaptic connections based on the cross-correlation analysis of their firing activities. We found that the spatial RF structure of both RGCs and LGN neurons were comparably elliptical and oriented in a direction toward the area centralis. Additionally, the spatial RF structures of pairs with the same response sign were often overlapped and similarly oriented. We also found there was a small population of pairs with RF structures that had the opposite response sign and were spatially displaced and independently oriented. Finally, the temporal RF structure of an RGC was tightly correlated with that of its target LGN neuron, though the response duration of the LGN neuron was significantly longer. Our results suggest that the elliptical RF structure of an LGN neuron is mainly inherited from the primary projecting RGC and is affected by convergent inputs from multiple RGCs. We discuss how the convergent inputs may enhance the stimulus feature sensitivity of LGN neurons.
Collapse
Affiliation(s)
- Naofumi Suematsu
- Laboratory of Cognitive and Behavioral Neuroscience, Department of Health and Sportsscience, Graduate School of Frontier Biosciences, Osaka University Osaka, Japan
| | - Tomoyuki Naito
- Laboratory of Cognitive and Behavioral Neuroscience, Department of Health and Sportsscience, Graduate School of Medicine, Osaka University Osaka, Japan
| | - Tomomitsu Miyoshi
- Department of Integrative Physiology, Graduate School of Medicine, Osaka University Osaka, Japan
| | - Hajime Sawai
- Department of Integrative Physiology, Graduate School of Medicine, Osaka University Osaka, Japan
| | - Hiromichi Sato
- Laboratory of Cognitive and Behavioral Neuroscience, Department of Health and Sportsscience, Graduate School of Frontier Biosciences, Osaka University Osaka, Japan ; Laboratory of Cognitive and Behavioral Neuroscience, Department of Health and Sportsscience, Graduate School of Medicine, Osaka University Osaka, Japan
| |
Collapse
|
16
|
Ghose D, Wallace MT. Heterogeneity in the spatial receptive field architecture of multisensory neurons of the superior colliculus and its effects on multisensory integration. Neuroscience 2013; 256:147-62. [PMID: 24183964 DOI: 10.1016/j.neuroscience.2013.10.044] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 10/08/2013] [Accepted: 10/22/2013] [Indexed: 11/15/2022]
Abstract
Multisensory integration has been widely studied in neurons of the mammalian superior colliculus (SC). This has led to the description of various determinants of multisensory integration, including those based on stimulus- and neuron-specific factors. The most widely characterized of these illustrate the importance of the spatial and temporal relationships of the paired stimuli as well as their relative effectiveness in eliciting a response in determining the final integrated output. Although these stimulus-specific factors have generally been considered in isolation (i.e., manipulating stimulus location while holding all other factors constant), they have an intrinsic interdependency that has yet to be fully elucidated. For example, changes in stimulus location will likely also impact both the temporal profile of response and the effectiveness of the stimulus. The importance of better describing this interdependency is further reinforced by the fact that SC neurons have large receptive fields, and that responses at different locations within these receptive fields are far from equivalent. To address these issues, the current study was designed to examine the interdependency between the stimulus factors of space and effectiveness in dictating the multisensory responses of SC neurons. The results show that neuronal responsiveness changes dramatically with changes in stimulus location - highlighting a marked heterogeneity in the spatial receptive fields of SC neurons. More importantly, this receptive field heterogeneity played a major role in the integrative product exhibited by stimulus pairings, such that pairings at weakly responsive locations of the receptive fields resulted in the largest multisensory interactions. Together these results provide greater insight into the interrelationship of the factors underlying multisensory integration in SC neurons, and may have important mechanistic implications for multisensory integration and the role it plays in shaping SC-mediated behaviors.
Collapse
Affiliation(s)
- D Ghose
- Department of Psychology, Vanderbilt University, Nashville, TN, United States; Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN, United States.
| | - M T Wallace
- Department of Psychology, Vanderbilt University, Nashville, TN, United States; Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN, United States; Department of Hearing and Speech Sciences, Vanderbilt University, Nashville, TN, United States; Department of Psychiatry, Vanderbilt University, Nashville, TN, United States; Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, United States
| |
Collapse
|
17
|
Effects of stimulus spatial frequency, size, and luminance contrast on orientation tuning of neurons in the dorsal lateral geniculate nucleus of cat. Neurosci Res 2013; 77:143-54. [PMID: 24055599 DOI: 10.1016/j.neures.2013.08.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 08/21/2013] [Accepted: 08/26/2013] [Indexed: 11/22/2022]
Abstract
It is generally thought that orientation selectivity first appears in the primary visual cortex (V1), whereas neurons in the lateral geniculate nucleus (LGN), an input source for V1, are thought to be insensitive to stimulus orientation. Here we show that increasing both the spatial frequency and size of the grating stimuli beyond their respective optimal values strongly enhance the orientation tuning of LGN neurons. The resulting orientation tuning was clearly contrast-invariant. Furthermore, blocking intrathalamic inhibition by iontophoretically administering γ-aminobutyric acid (GABA)A receptor antagonists, such as bicuculline and GABAzine, slightly but significantly weakened the contrast invariance. Our results suggest that orientation tuning in the LGN is caused by an elliptical classical receptive field and orientation-tuned surround suppression, and that its contrast invariance is ensured by local GABAA inhibition. This contrast-invariant orientation tuning in LGN neurons may contribute to the contrast-invariant orientation tuning seen in V1 neurons.
Collapse
|