phenomenon · claim-type · cross-domain-transfer · mechanism · claim-relation · replication-status · limitation — grounded in the full text| phenomenon | bidirectional optogenetic control of individual inhibitory neurons in freely-moving mice— “Using these devices, the same cortical PV cell could be activated and silenced.” | |
| claim-type | method— “We developed a lens-free approach for constructing dual-color headmounted, fiber-based optical units: any two wavelengths can be combined.” | |
| method — evidence | — “Here, we present a novel design for a dual-color, headmounted, fiber-optic based device combined with recording electrodes.” | |
| transfer | from laser optics / photonics: The simple astigmatic Gaussian beam model, a solution of the paraxial Helmholtz equation from laser-beam physics, is imported to predict coupling efficiency and set the optical pathway lengths of the implantable neural device.— “Like the Gaussian beam model, the SAG model is a solution of the paraxial Helmholtz equation.” | transfers[0] |
| mechanism | Choosing an inhibitory (PV) opsin-expressing cell reverses the sign of the expected synaptic side-effect, so any blue-light-driven rate increase in the tagged cell must come from direct illumination rather than from trans-synaptic drive— “when the opsin-expressing cell is inhibitory, synaptic effects are reversed and any rate increase following blue light illumination stems from direct illumination (with the caveat of disynaptic dis-inhibition).” | mechanisms[0] |
| mechanism | Optically driven PV cells inhibit their postsynaptic pyramidal partners, so activating the PV cell lowers pyramidal firing and silencing it raises pyramidal firing— “These observations are consistent with inhibitory synaptic connections between the optically manipulated PV cells and the putative PYR” | mechanisms[1] |
| mechanism | a recorded neuron can inherit a rate change it never received light for With excitatory-cell expression, a non-illuminated opsin-free neuron may inherit a rate increase or decrease through glutamatergic connections from directly illuminated pre-synaptic neurons - which is why the inhibitory-cell design reverses the sign and makes the inference possible.— “a nonilluminated/opsin-free recorded neuron may inherit a rate increase/decrease via glutamatergic connections from directlyilluminated, opsin-expressing pre-synaptic neurons” | mechanisms[2] |
| extends | the authors' earlier GRIN-lens waveguide dual-color device (references [16], [17])— “We have recently reported such an advance [16], [17], but that approach was tailored to specific wavelengths (405 and 638 nm), required custom-made parts (e.g. GRIN lenses), utilized a full nanofabrication facility, and was applied only to head-fixed anesthetized animals.” | claim_relations[0] |
| extends | previous demonstrations of activating and silencing the same neuron in brain slices, a head-fixed mouse and a freely-moving rat (references [8], [26], [16], [15])— “This is not the first time that the same neuron is both activated and silenced optically: previous demonstrations were in brain slices [8], [26], in a head-fixed mouse [16], and in a freely-moving rat [15].” | claim_relations[1] |
| sense | evidence of direct optogenetic activation - a rate increase after blue light, whose interpretation REVERSES depending on whether the opsin-expressing cell is excitatory or inhibitory— “when the opsin-expressing cell is inhibitory, synaptic effects are reversed and any rate increase following blue light illumination stems from direct illumination” | senses[0] |
| sense | feasibility - established by a PREDICTIVE MODEL of alternative optical designs before any unit was built, so the design was selected against a model rather than against measurements— “To test the feasibility of several alternative optical designs, a predictive model was devised.” | senses[1] |
| sense | rate increase - evidence of DIRECT illumination only because the illuminated cell is inhibitory, so the synaptic route would lower the rate; the one surviving alternative, disynaptic dis-inhibition, is named as a caveat— “when the opsin-expressing cell is inhibitory, synaptic effects are reversed and any rate increase following blue light illumination stems from direct illumination (with the caveat of disynaptic dis-inhibition)” | senses[2] |
| control | a baseline recording period of at least 15 minutes preceding photostimulation in every session — held— “At each location in the brain, neuronal activity was inspected for spontaneous spiking activity, and if encountered, a full recording session (>3 hours) was conducted.” — rules out that the spiking and LFP changes attributed to photostimulation were already present before the light was applied— “The session consisted of a baseline period of at least 15 min, followed by photostimulation.” | controls[0] |
| evidence status note | rate increase —distinct-from→ disynaptic dis-inhibition — THE QUOTE CONTINUES A SENTENCE THAT THIS COPY CUTS IN TWO - a figure caption (Fig. 9) and an author-contribution block stand between it and the words it follows, which are not adjacent to it in the extraction.— “when the opsin-expressing cell is inhibitory, synaptic effects are reversed and any rate increase following blue light illumination stems from direct illumination (with the caveat of disynaptic dis-inhibition)” | concept_edges[0] |
| note | rate increase —distinct-from→ disynaptic dis-inhibition — THE PAPER NAMES THE CONFOUND IN THE SENTENCE THAT MAKES THE INFERENCE. Choosing an INHIBITORY cell reverses the expected synaptic sign, so a rate increase after blue light can only be direct illumination - 'with the caveat of disynaptic dis-inhibition'. The design turns a confound into a signature, and the one route that survives is stated in the same breath rather than left to a reader.— “when the opsin-expressing cell is inhibitory, synaptic effects are reversed and any rate increase following blue light illumination stems from direct illumination (with the caveat of disynaptic dis-inhibition)” | concept_edges[0] |
| weight | rate increase —distinct-from→ disynaptic dis-inhibition — 0.9— “when the opsin-expressing cell is inhibitory, synaptic effects are reversed and any rate increase following blue light illumination stems from direct illumination (with the caveat of disynaptic dis-inhibition)” | concept_edges[0] |
| outcome | control — held— “The session consisted of a baseline period of at least 15 min, followed by photostimulation.”— “At each location in the brain, neuronal activity was inspected for spontaneous spiking activity, and if encountered, a full recording session (>3 hours) was conducted.” | controls[0] |
| for which use | limitation — any plan to build these at scale: ASSEMBLING A SINGLE DUAL-COLOR OPTICAL UNIT REQUIRES ABOUT SIX HOURS OF WORK— “The main disadvantage of the presented approach is assembly duration: assembling a single dual-color optical unit requires about six hours of work.” | limitations[0] |
| for which use | limitation — how many units a small animal can carry: EACH UNIT WEIGHS OVER 0.5 g— “A second limitation is the size of the unit: although lighter than optical tables by four or five orders of magnitude, each unit weighs over 0.5 g.” | limitations[1] |
| for which use | limitation — the bidirectional control claim for the population: A THIRD LIMITING FACTOR IS THE PERCENTAGE OF PV INTERNEURONS WITH DOUBLE EXPRESSION OF BOTH CaMKII AND JAWS— “A third limiting factor is the percentage of PV interneurons with double expression of both CaMKII and Jaws.” | limitations[2] |
| for which use | limitation — reading a light-evoked rate increase in an inhibitory cell as direct activation: the paper states this holds with the caveat of disynaptic dis-inhibition— “any rate increase following blue light illumination stems from direct illumination (with the caveat of disynaptic dis-inhibition).” | limitations[3] |
| for which use | limitation — the wavelengths and powers available in this device: the diodes were chosen to fit a 3.8 mm can, a 100 mA maximal current limitation and low threshold currents— “The physical requirements were met using ø3.8 mm Transistor Outline (TO) can LDs. To maximize the dynamic range of the light output, we chose LDs that can operate within the maximal current limitation of 100 mA and have low threshold currents.” | limitations[4] |
| evidence status note | mechanism — THE QUOTE CONTINUES A SENTENCE THAT THIS COPY CUTS IN TWO - a figure caption (Fig. 9) and an author-contribution block stand between it and the words it follows, which are not adjacent to it in the extraction.— “when the opsin-expressing cell is inhibitory, synaptic effects are reversed and any rate increase following blue light illumination stems from direct illumination (with the caveat of disynaptic dis-inhibition).” | mechanisms[0] |
| evidence status note | sense — THE QUOTE CONTINUES A SENTENCE THAT THIS COPY CUTS IN TWO - a figure caption (Fig. 9) and an author-contribution block stand between it and the words it follows, which are not adjacent to it in the extraction.— “when the opsin-expressing cell is inhibitory, synaptic effects are reversed and any rate increase following blue light illumination stems from direct illumination” | senses[0] |
| evidence status note | sense — THE QUOTE CONTINUES A SENTENCE THAT THIS COPY CUTS IN TWO - a figure caption (Fig. 9) and an author-contribution block stand between it and the words it follows, which are not adjacent to it in the extraction.— “when the opsin-expressing cell is inhibitory, synaptic effects are reversed and any rate increase following blue light illumination… | senses[2] |
| replication | untested | |
| limitation | Each dual-color unit takes about six hours of manual assembly. | limitations[0] |
| limitation | Unit weight over 0.5 g caps how many can be mounted on a small animal. | limitations[1] |
| limitation | Only a fraction of PV interneurons expressed both opsins, so not all blue-responsive cells were also red-responsive. | limitations[2] |
| limitation | The inference from a rate increase to direct illumination carries a named exception, and it is stated inside the sentence the conclusion is drawn from. | limitations[3] |
| limitation | The design space is bounded by what is commercially available and by the physical envelope, not by what the experiment would ideally need. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[4] |
| limitation | The design space was bounded by the model before it was bounded by experiment: butt-coupling was excluded on modelled grounds, so the reported geometry is the survivor of a simulated elimination rather than a measured comparison. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[5] |
finding · quantity · variable · definition · key-term — grounded in the full text| finding | The dual-color unit delivered 454±271 µW at 450 nm and 8.65±2.26 mW at 638 nm at the fiber tip at 100 mA. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[0] |
| finding | The blue and red illumination profiles from the shared fiber overlapped by 46%. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[1] |
| finding | The two wavelengths did not interact optically: their spectra at the fiber end were separate and no spectral interference occurred during simultaneous dual-color illumination. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[2] |
| finding | Nine of 74 interneurons (12%) were controlled bidirectionally through the same fiber, raising their spike rate under blue light and lowering it under red light. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[3] |
| finding | Blue light produced stronger effects than red light. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[4] |
| finding | The second-order effects on pyramidal cells were strictly sign-appropriate for inhibition: no pyramidal cell was excited by blue light and none was suppressed by red light. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[5] |
| finding | Laser heating did not exceed 7 °C even under prolonged pulsed illumination. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[6] |
| finding | Wide-band recordings during blue and red illumination were clean. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[7] |
| finding | The paper claims the first conclusive demonstration that a single identified neuron can be both activated and silenced in a freely-moving animal. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[8] |
| finding | The approach's main cost is labour: each dual-color optical unit takes roughly six hours to assemble. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[9] |
| quantity | 454±271 µW and 8.65±2.26 mW — Light power at the etched fiber tip at 100 mA drive current for the 450 nm and 638 nm laser diodes respectively Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[0] |
| quantity | 46% — Spatial overlap (intersection over union) of the blue and red illumination profiles at the fiber tip Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[1] |
| quantity | 630±55 mg — Average weight of one assembled dual-color optical unit Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[2] |
| quantity | 2.77 g — Weight of a complete implantation-ready four-shank dual-color probe with microdrive Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[3] |
| quantity | 230 — Total number of well-isolated cells recorded from neocortex and CA1 across the three mice Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[4] |
| quantity | 36 of 80 INT; 45% — Proportion of recorded interneurons that increased their spike rate during blue-light illumination Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[5] |
| quantity | 37/77, 48% — Proportion of recorded interneurons that decreased their spike rate during red-light illumination through the same fiber Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[6] |
| quantity | 9/74 of the INT; 12% — Proportion of interneurons controlled bidirectionally (activated by blue and silenced by red) Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[7] |
| quantity | h= 0.61±0.04 — Effect size of the blue-light-driven firing-rate increase in responsive interneurons Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[8] |
| quantity | 7 °C — Maximum on-head temperature rise of the laser can during prolonged illumination in a behaving mouse Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[9] |
| quantity | under 31°C — Peak bench-test temperature of an optical unit under prolonged high-load operation, below mammalian body temperature Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[10] |
| quantity | 1.14±0.11 MΩ — Impedance of each silicon-probe recording site measured at 1 kHz in saline Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[11] |
| quantity | 14.9±5.3 MΩ — Electrical isolation between diode anode-cathode and the grounded Faraday shield, high enough to make EMI negligible Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[12] |
| quantity | three freely-moving male mice — Number of animals implanted, all heterozygous for PV-Cre and expressing ChR2 and Jaws in PV interneurons Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[13] |
| quantity | about six hours — Assembly time for a single dual-color optical unit, the method's main practical cost Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[14] |
| variable | driving current (independent) Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.variables[1] |
| variable | spike rate (dependent) Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.variables[2] |
| variable | light power (dependent) Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.variables[3] |
| variable | device temperature (dependent) Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.variables[4] |
| variable | epochs with no stimulation (control) Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.variables[5] |
| variable | inhibitory cell type (control) Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.variables[6] |
| definition | SAG model Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.definitions[0] |
| concept | disynaptic dis-inhibition Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[0] |
| concept | predictive model Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[1] |
| concept | laser diode Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[2] |
| concept | ChR2 Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[3] |
| concept | rate increase Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[4] |
| Mann-Whitney U test p | Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[0] |
| binomial test p | as written: exact Binomial test Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[1] |
| Poisson test p | Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[2] |
| effect size h | as written: The effect size for these units was h= Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[3] |
| principal component analysis | as written: principal component analysis of the data Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[4] |
| Gaussian mixture model p | Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[5] |
| evidence status note | Gaussian mixture model — THE QUOTE CONTINUES A SENTENCE THAT THIS COPY CUTS IN TWO - a figure caption (Fig. 6) and a running head stand between it and the words it follows, which are not adjacent to it in the extraction. | content_tags.statistics[5] |
| confidence bands | as written: 99.9% global confidence bands Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[6] |
| mean and standard deviation SD | as written: mean±SD Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[7] |
| standard error of the mean | as written: mean ± standard error of the mean Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[8] |
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