Barrel Cortex as a Model System for Understanding the Molecular, Structural, and Functional Basis of Cortical Plasticity

Fox, Kevin; Greenhill, Stuart; Haan, Annelies de

doi:10.1016/b978-0-12-812028-6.00010-0

Cited by 3 publications

(2 citation statements)

References 63 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Responses were averaged over 50 stimuli and defined as spikes produced during a 3-53 ms following stimulation. Details of recording methods can be found previously (Fox, 1992;Fox et al, 2018). Mice were perfused with PFA and cryoprotected with sucrose before the brains were flattened for sectioning using a freezing microtome.…”

Section: Methodsmentioning

confidence: 99%

Dual-Component Structural Plasticity Mediated by αCaMKII Autophosphorylation on Basal Dendrites of Cortical Layer 2/3 Neurones

et al. 2020

Self Cite

View full text Add to dashboard Cite

Sensory cortex exhibits receptive field plasticity throughout life in response to changes in sensory experience and offers the experimental possibility of aligning functional changes in receptive field properties with underpinning structural changes in synapses. We looked at the effects on structural plasticity of two different patterns of whisker deprivation in male and female mice: chessboard deprivation, which causes functional plasticity; and all deprived, which does not. Using 2-photon microscopy and chronic imaging through a cranial window over the barrel cortex, we found that layer 2/3 neurones exhibit robust structural plasticity, but only in response to whisker deprivation patterns that cause functional plasticity. Chessboard pattern deprivation caused dual-component plasticity in layer 2/3 by (1) increasing production of new spines that subsequently persisted for weeks and (2) enlarging spine head sizes in the preexisting stable spine population. Structural plasticity occurred on basal dendrites, but not apical dendrites. Both components of plasticity were absent in ␣CaMKII-T286A mutants that lack LTP and experience-dependent potentiation in barrel cortex, implying that ␣CaMKII autophosphorylation is not only important for stabilization and enlargement of spines, but also for new spine production. These studies therefore reveal the relationship between spared whisker potentiation in layer 2/3 neurones and the form and mechanisms of structural plasticity processes that underlie them.

show abstract

Section: Methodsmentioning

confidence: 99%

Dual-Component Structural Plasticity Mediated by αCaMKII Autophosphorylation on Basal Dendrites of Cortical Layer 2/3 Neurones

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…Following the insertion of the probe, a piezo-electric whisker stimulator was used to deflect the whisker (Physik Instrumente, UK) (Fox et al, 2018). The working principal whisker was chosen based on the peak response to stimulation assessed by the LFP, unit sensory response and the number of channels with putative sensory response.…”

Section: Acute In Vivo Electrophysiology In Micementioning

confidence: 99%

Interdependence of primary and secondary somatosensory cortices for plasticity and texture discrimination learning

Pandey

Kang

Pacchiarini

et al. 2023

Preprint

Self Cite

View full text Add to dashboard Cite

Feedforward and feedback pathways are important for transfer and integration of information between sensory cortical areas. Here we find that two closely connected cortical areas, the primary (S1) and secondary somatosensory cortices (S2) are both required for mice to learn a whisker-dependent texture discrimination. Increased inhibition in either area (using excitatory DREADDs expressed in inhibitory interneurones) prevents learning. We find that learning the discrimination produces structural plasticity of dendritic spines on layer 2/3 pyramidal neurones in vibrissae S1 that is restricted to the basal dendrites and leaves dendritic spines on apical dendrites unchanged. As S2 projects to the apical dendrites of S1 neurones, we tested whether S2 affects LTP-induction in S1. We found that feedback projections from S2 to S1 gates LTP on feedforward pathways within S1. These studies therefore demonstrate the interdependence of S1 and S2 for learning and plasticity in S1.

show abstract

Quintuple AISI 1010 carbon steel core coil for highly focused transcranial magnetic stimulation in small animals

et al. 2021

View full text Add to dashboard Cite

Transcranial magnetic stimulation (TMS) is a non-invasive neuromodulation technique used to regulate the synaptic activity of neurons in the brain, improving the functionality of connecting regions and bringing effective treatment to different neurological and psychiatric disorders. The TMS induced E-field needs to be focal enough to avoid unwanted side effects caused by stimulation of the regions adjacent to the target. Attempts at TMS in small animals like rodents are highly constrained, since most of these studies use commercial equipment intended for humans, with power and coil geometries not designed for small animals. Using finite element modeling in ANSYS Maxwell, the present work shows the design and evaluation of customized arrays of two and five dual-winding solenoids, including a ferromagnetic core, to restrict the stimulation to areas as small as 1 mm2. Each solenoid is made with 50 turns of a wire with thickness = 1 mm, height = 25.4 mm and elliptical top-view cross section. Ferromagnetic cores with V-shape tip sharpening were included, using AISI 1010 carbon steel of 2 T of saturation flux density (Bsat) at 4×104 A/m, and an initial relative permeability µr=667.75. Electric fields and magnetic flux densities were calculated around 4.00 mm below the coil (vertical distance from the top of the scalp to the cortical layer 5/6 in adult rats) with peak currents of 10kA, in a single non-repetitive pulse at 2.5kHz. The achieved 100V/m in a small area of 1 mm2 suggests the suitability of the coil for in vivo experimentation in rodents. Future works will seek to improve the duration of the pulses for repetitive TMS with pulse shaping techniques and validate the novel coil with in vivo experiments in rat models.

show abstract

Barrel Cortex as a Model System for Understanding the Molecular, Structural, and Functional Basis of Cortical Plasticity

Cited by 3 publications

References 63 publications

Dual-Component Structural Plasticity Mediated by αCaMKII Autophosphorylation on Basal Dendrites of Cortical Layer 2/3 Neurones

Dual-Component Structural Plasticity Mediated by αCaMKII Autophosphorylation on Basal Dendrites of Cortical Layer 2/3 Neurones

Interdependence of primary and secondary somatosensory cortices for plasticity and texture discrimination learning

Quintuple AISI 1010 carbon steel core coil for highly focused transcranial magnetic stimulation in small animals

Contact Info

Product

Resources

About