Neocortical basket cells
Neo cortical Basket Cell is a neuron found in vertebrates
Neo cortical Basket cell
Basket Cells were first described by Cajal in the motor and visual cortex of the human brain. They are small, medium-sized, and large multipolar neurons, whose diameters vary from 12 to 30 µm and whose bodies are located in layers II–VI . BC terminals--basket plexuses and pericellular nestles contact with bodies, axonalhillock and proximal regions of pyramidal neurons dendrites and double-bouquet cells, forming reciprocal relations with them in accordance with domain-selection principle. BC establish ties between each other and interconnect by means of autapses
Neuronal Type: Interneuron.
Variety and Topographical characteristics
BC dendrites are smooth or have few spines, and they appear to have no other specific characteristics. Basket neurons are distinguished from other cortical interneurons by their axons, which pass predominantly in the vertical and horizontal directions. They form long (up to300–700 µm), extensively arborized or straight branch rays in the horizontal, oblique, and vertical directions, covering large areas of the cortex with diameters of up to 1400 µm. A second morphological characteristic is provided by the axon terminals – vertically orientated filaments with large beads and basket-like plexuses or pericellular holes.
Input Receptors: Glutamate at Distal equivalent dendrite and Gaba at Proximal equivalent dendrites and soma. Output transmitters: Gaba (Gamma-amino butyric acid) acts as output transmitter at Axon terminal.
Anatomical, electrophysiological and molecular diversity of basket cell-like interneurons in layers II–IV of rat somatosensory cortex were studied using patch-clamp electrodes filled with biocytin. This multiparametric study shows that neocortical basket cells (BCs) are composed of three distinct subclasses: classical large (LBC) and small (SBC) basket cells and a third subclass, the nest basket cell (NBC). Anatomically, NBCs were distinct from LBCs and SBCs in that they formed simpler dendritic arbors and an axonal plexus of inter-mediate density, composed of a few long, smooth axonal branches. Electro physiologically, NBCs exhibited diverse discharge responses to depolarizing current injections including accommodation, non-accommodation and stuttering
A hypothesis according to which basket plexus may be thought of as an inhibiting integrator, equaling excitation in a cluster of several pyramidal cells is under substantiation
- S. Ramon y Cajal, Histologie du Systeme Nerveux de l’Homme et des Vertebres, Maloine, Paris (1911), Vol. II.
- Okhotin VE Kalinichenko SG. [Histophysiology of neocortical basket cells]. Morfologiia (Saint Petersburg, Russia). 2001;120(4):7-24.
- The Histophysiology of Neocortical Basket Cells V. E. Okhotin and S. G. Kalinichenko, Neuroscience and Behavioral Physiology, Vol. 32, No. 5, 2002
- Anatomical, physiological, molecular and circuit properties of nest basket cells in the developing somatosensory cortex.Wang Y, Gupta A, Toledo-Rodriguez M, Wu CZ, Markram H. PMID: 11884355
Neocortical Basket cells are inhibitory GABAergic neurons located in the cortex of all vertebrates. These neurons are involved in intramodule, lateral, and callosal inhibition. They are termed basket cells due to basket-plexuses that are formed around other cell types within the nervous system.
Neuronal Type: Local Interneuron
Neocortical basket cell bodies are located in layers II-VI or the cortex. They have diameters that range from 12 to 30 µm. Their dendrites are either smooth or have very few spines and their axons mostly pass in the vertical and horizontal direction. A distinguishing physiological feature is that their axon terminal are vertically oriented with large beads and basket-like plexuses or pericellular holes. Basket cells make up the largest population of inhibitory neurons.
 Molecular profile
• Neurotransmitter: GABA (Gamma-Aminobutyric Acid) is the most abundant neurotransmitter in the central nervous system. GABA works by in inhibiting the over-firing of neurons in the brain, or simply by blocking the transmission of an impulse from one cell to another. It is important in the motor and visual cortex.
• Molecular Markers: Parvalbumin is a calcium binding albumin protein. Interneurons are labeled as either PV+ or PV-. Neocortical Basket Cells are PV+. The production of parvalbumin is thought to be responsible for increased neuron activity and as a result these neurons are labeled as fast spiking cells.
Neocortical basket cells are physiologically unique due to the varying locations within the cortex.
Layer II the basket cells dendrites may extend for 200-250 µm vertically from the neuron body and the axon passes along the boundary between layers II and III. Layer III the basket cell dendrites are smooth. The axon forms a local plexus around the dendritic field and sends out arborized branches directed into layer II. Layer V has cell bodies approximately 15 µm in diameter with axons directed into upwards layers.
 Synaptic Connections
 Synaptic Inputs
Neocortical Basket Cells receive synapses from the reverse collaterals of pyramidal neuron axons and also receive axodendritic synapses from double bouquet cells. They also receive inputs from GABAergic afferent fibers and corticopetal dopaminergic fibers.
 Synaptic Outputs
Neocortical Basket Cells form perisomatic synapses on double bouquet cells, arcades, and dendrite-targeting cells.
 Spiking properties
Neocortical basket cells exhibit tonic spiking. Therefore, they are known as Fast Spiking (FS) inhibitory neurons. The behavior of spiking in neocortical basket cells is linked with increases in the content of calcium ions, which activates potassium ion conductivity, and leads to the development of hyperpolarization. The spiking behavior of the neurons in mediated by excitation of NMDA receptors.
Neocortical basket cells are key interneurons in lateral inhibition which is primarily involed in visual behavior, such as retinal organization. This behavior is responsible for our perception of optical illusions. The cells are also key in callosal inhibiton which is responsible for our ability to process language. Lastly these neurons are key in intramodule (intracolumn) inhibiton which is responsible for short term memory.
1. Kalinichenko S.G., Okhotin V.E. (2002) The Histophysiology of Neocortical Basket Cells, Neuroscience and Behavioral Physiology, 32: 455-470.
2. Conn P.M (2003) Neuroscience in Medicine. 231-232
3. Wang Y., Gupta A., Toledo-Rodriguez M., Wu C.Z., Markram H. (2002) Anatomical, Physiological, Molecular, and Circuit Properties of Nest Basket Cells in the Developing Somatosensory Cortex, 12:4. 395-410.