2. Transduction of Sensory Receptors Transduction: The process by which an environmental stimulus becomes encoded as a sequence of nerve impulses in an afferent nerve fiber is called sensory transduction -Sense orgrans transduce sensory energy into neural (bioelectrical) energy Converting one type of energy into another type is the process of transduction Your brain only deals with bioelectrical impulses so transduction must occur. what cannot be transduced cannot be a stimulus
2.Transduction of Sensory Receptors Transduction: The process by which an environmental stimulus becomes encoded as a sequence of nerve impulses in an afferent nerve fiber is called sensory transduction –Sense orgrans transduce sensory energy into neural (bioelectrical) energy –Converting one type of energy into another type is the process of transduction –Your brain only deals with bioelectrical impulses so transduction must occur; what cannot be transduced cannot be a stimulus
Principles of transduction Different kinds of receptor are activated in different ways but the first stage in sensory transduction is the generation of a graded receptor potential The magnitude of the stimulus is related to that of the receptor potential which in turn is related to either a) the sequence or frequency of all-or-none action potentials generated in the afferent nerve fiber b) modulated release of transmitter from the receptor cell generating a sequence of action potentials in a second order neurone
Principles of Transduction • Different kinds of receptor are activated in different ways but the first stage in sensory transduction is the generation of a graded receptor potential. • The magnitude of the stimulus is related to that of the receptor potential which in turn is related to either a) the sequence or frequency of all-or-none action potentials generated in the afferent nerve fiber; b) modulated release of transmitter from the receptor cell generating a sequence of action potentials in a second order neurone
Receptor/Generator potential Receptor potentials: Changes in the transmembrane potential of a receptor caused by the stimulus Generator Potential: A receptor potential that is strong enough(reaches threshold) to generate an action potential Remember that aps are all-or-none The stronger the sitmulus(above threshold) the more APs are fired over a given time period this is translated by the cns as a strong sensation
Receptor/Generator Potential Receptor potentials: Changes in the transmembrane potential of a receptor caused by the stimulus. Generator Potential: A receptor potential that is strong enough (reaches threshold) to generate an action potential. Remember that APs are all-or-none. The stronger the sitmulus (above threshold) the more APs are fired over a given time period; this is translated by the CNS as a strong sensation
3. Adaptation of Sensory Receptor
3. Adaptation of Sensory Receptor
Sensory Adaptation is one form of Integration Phasic receptors quickly (b)Rapidly adap adapt. The frequency of onIc recept phasic recepto Stimulus Stimulus action potentials diminishes or stops if the stimulus is unchanging Generator Tonic receptors adapt slowly or not at al Axon of Most exteroreceptors neuron (receptors that monitor the external environment) are phasic receptors
Sensory Adaptation is one form of Integration Phasic receptors quickly adapt. The frequency of action potentials diminishes or stops if the stimulus is unchanging. Tonic receptors adapt slowly or not at all. Most exteroreceptors (receptors that monitor the external environment) are phasic receptors