The sensory quality experienced such as from a sound touch or light depends on

The sensory quality experienced such as from a sound

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The sensory quality experienced, such as from a sound, touch or light, depends on which nerve is stimulated, not on how it is stimulated It is not the form of physical energy that determines the nature of the sensation, but rather the specificity of the neurons, receptors, and nerves activated by the stimulus Every sensory domain has an adequate stimulus – a type of physical energy to which it is more or less uniquely sensitive Just-Noticeable Difference Minimum level of detectable difference in the magnitude of a stimulus The smaller your “just-noticeable” difference is, the more sensitive you are Sensory Adaptation Fatigue : Neurons that are subjected to steady, continuous stimulation become unable to send signals, probably because of a temporary depletion in the neurotransmitters that send signals across synapses find more resources at oneclass.com find more resources at oneclass.com
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Adaptation : a change, usually a decrease, in sensitivity that occurs when a sensory system is repeatedly stimulated in exactly the same way Sensory adaptation : a change, usually a decrease, in sensitivity that occurs when a sensory system is repeatedly stimulated in exactly the same way Happens in all sensory domains and is defined as a change in sensitivity Neural Codes All sensory systems have specialized receptor cells that detect the energy and convey signals to the brain (through neural firing) about the presence of environmental stimuli Receptor cells can convey different kinds of information These energies, combined with the Doctrine of Specific Nerve Energies , form the basis of sensation How Adaption Works For neurons to use a “temporal code” means that psychologically important information is coded in the firing rate of neurons When no stimulus is present, nerve cells still fire randomly, at some spontaneous rate Spontaneous rate : rate of neuronal firing when no stimulus is present If a neuron isn’t fatigued, then the rate of firing indicates the intensity of a stimulus – how strong it is Weak stimuli will increase the firing rate a little bit Strong stimuli increase it a lot If a neuron becomes fatigued as a result of adaptation, its rate of signaling may fall below the spontaneous rate, or minimum detectable level, and your body no longer notices the stimulus Multisensory : relating to or involving more than one physiological sense Cranial Nerves It is twelve pairs of nerve fibers that travel into and out of the skull and carry all sensory information (except for somatosenses) from parts of the body below the neck to the brain The skull is a protective bony case with only a few holes in it - 12 cranial nerves pass through these holes Some nerves are all sensory (afferent), some are exclusively motor (efferent), and some serve both sensory and motor functions What is Light?
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