Neuronal tuning
Encyclopedia
Neuronal tuning refers to the property of brain cells to selectively represent a particular kind of sensory, motor, or cognitive information. For example, an auditory system neuron best responding to the sound of particular frequency is said to be tuned to that frequency. In the visual system, there are neurons tuned to particular objects, for example faces. In the motor system, tuning to movement direction has been described. Neuronal tuning is not necessarily sharp. Rather, it can be quite broad. In the latter case, neuroscientist
Neuroscientist
A neuroscientist is an individual who studies the scientific field of neuroscience or any of its related sub-fields...

s often argue that information is represented in distributed manner by neural ensemble
Neural ensemble
A neural ensemble is a population of nervous system cells involved in a particular neural computation.- Background :The concept of neural ensemble dates back to the work of Charles Sherrington who described the functioning of the CNS as the system of reflex arcs, each composed of interconnected...

s. In an ensemble, individual elements can be weakly tuned, but the ensemble as a whole still encodes the information.

One neuron can be tuned to several parameters. Examples include neurons in association areas of cerebral cortex
Cerebral cortex
The cerebral cortex is a sheet of neural tissue that is outermost to the cerebrum of the mammalian brain. It plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness. It is constituted of up to six horizontal layers, each of which has a different...

 that respond to stimuli of different modality (for example, visual stimulation, touch, sound). The field of brain-computer interface
Brain-computer interface
A brain–computer interface , sometimes called a direct neural interface or a brain–machine interface , is a direct communication pathway between the brain and an external device...

 makes use of such neurons by reading-out different kind of information from their firing, for example simultaneous decoding of hand velocity and hand gripping force. In prefrontal cortex
Prefrontal cortex
The prefrontal cortex is the anterior part of the frontal lobes of the brain, lying in front of the motor and premotor areas.This brain region has been implicated in planning complex cognitive behaviors, personality expression, decision making and moderating correct social behavior...

, neurons have been described that simultaneously encode information about the orientation of selective visual attention
Attention
Attention is the cognitive process of paying attention to one aspect of the environment while ignoring others. Attention is one of the most intensely studied topics within psychology and cognitive neuroscience....

  and short-term visual memory
Memory
In psychology, memory is an organism's ability to store, retain, and recall information and experiences. Traditional studies of memory began in the fields of philosophy, including techniques of artificially enhancing memory....

 (Attention versus memory in prefrontal cortex
Attention versus memory in prefrontal cortex
A widely accepted theory regarding the function of the brain's prefrontal cortex is that it serves as a store of short-term memory. This idea was first formulated by Jacobsen, who reported in 1935 that damage to the primate prefrontal cortex caused short-term memory deficits...

). Neurons that are tuned to different signals are often said to integrate information from different sources. In neural networks
Neural Networks
Neural Networks is the official journal of the three oldest societies dedicated to research in neural networks: International Neural Network Society, European Neural Network Society and Japanese Neural Network Society, published by Elsevier...

, such integration is the major principle of operation.
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