Answer: the reciprocal of the interspike interval and measured in hertz
The frequency of action potentials is _______.
Several types of cells support an action potential such as plant cells muscle cells and the specialized cells of the heart (in which occurs the cardiac action potential). However the main excitable cell is the neuron which also has the simplest mechanism for the action potential. Neurons are electrically excitable cells composed in general of one or more dendrites a single soma a single axon and one or more axon terminals. Dendrites are cellular projections whose primary function i…
A sequence or 'train' of spikes may contain information based on different coding schemes. In motor neurons for example the strength at which an innervated muscle is contracted depends solely on the 'firing rate' the average number of spikes per unit time (a 'rate code'). At the other end a complex 'temporal code' is based on the precise timing of single spikes. They may be locked to an external stimulus such as in the visual and auditory system or be generated intrinsically by the neural circuitry. Whether neurons use rate coding or temporal coding is a topic of intense debate within the ne…
A sequence or 'train' of spikes may contain information based on different coding schemes. In motor neurons for example the strength at which an innervated muscle is contracted depends solely on the 'firing rate' the average number of spikes per unit time (a 'rate code'). At the other end a complex 'temporal code' is based on the precise timing of single spikes. They may be locked to an external stimulus such as in the visual and auditory system or be generated intrinsically by the neural circuitry. Whether neurons use rate coding or temporal coding is a topic of intense debate within the neuroscience community even though there is no clear definition of what these terms mean. The rate coding model of neuronal firing communication states that as the intensity of a stimulus increases the frequency or rate of action potentials or "spike firing" increases. Rate coding is sometimes called frequency coding. Rate coding is a traditional coding scheme assuming that most if not all information about the stimulus is contained in the firing rate of the neuron. Because the sequence of action potentials generated by a given stimulus varies from trial to trial neuronal responses are typically treated statistically or probabilistically. They may be characterized by firing rates rather than as specific spike sequences. In most sensory systems the firing rate increases generally non-linearly with increasing stimulus intensity. Under a rate coding assumption any information possibly encoded in the temporal structure of the spike train is ignored. Consequently rate coding is inefficient but highly robust with respect to...
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