Sensations

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Definition

Sensation
G . KIM BIGLEY Proprioceptive sensation (also termed deep sensation) : receptors located in muscles, tendons, ligaments and joints Joint position sense (arthresthesia) : Absence is described as such Vibratory sense (pallesthesia) : Absence is described as such Kinesthesia : perception of muscular motion . Usually not measured in routine clinical evaluation . Cortical sensory functions: interpretative sensory functions that require analysis of individual sensory modalities by the parietal lobes to provide discrimination . Individual sensory modalities must be intact to measure cortical sensation . Stereognosis : ability to recognize and identify objects by feeling them . The absence of this ability is termed astereognosis . Graphesthesia: ability to recognize symbols written on the skin. The absence of this ability is termed graphanesthesia . Two-point discrimination : ability to recognize simultaneous

The sensory system provides information that places the individual in relation to the environment . Sensation may be classified into categories by various methods dependent on anatomic or functional criteria . An anatomic classification divides sensory function into somatic and visceral components with general and special subgroups of each . Clinically, however, only somatic sensation is easily measured . One functional classification separates sensory modalities into simple affective sensations, termed protopathic, and sensations that provide discriminative analysis with regard to the environment, termed epicritic . A more practical scheme of classification was developed early in this century by Sherrington and remains the most useful for the clinician . This scheme utilizes both anatomic criteria including the types and locations of end organs and functional criteria such as the types of stimuli measured by each modality to separate exteroceptive and proprioceptive sensation . A third sensory modality requires cortical analysis to