Biomaterial Database

Behavioral measures of auditory thresholds in developing tree shrews (Tupaia belangeri). 1993

E Zimmermann

Faculty of Biology, University of Konstanz, Germany.

The development of hearing in tree shrews (Tupaia belangeri) was tested through behavioral measures in the range of 0.3-60 kHz from the first postnatal thresholds detectable through to those of weanlings. The onset of hearing was defined using unconditioned startle responses, while, later on, pinna reflexes and head movements were used as behavioral indicators of sound perception. Startle responses could be evoked from day 16 after birth (DAB) onwards, indicating that the hearing system is capable of transferring airborne sound, although no reactions to tones were recorded at this age. The first unconditioned reactions to tones were found at DAB 18 in the range of 1-5 kHz (range of mother-infant call). Responses were restricted to the range of greatest sensitivity in adults (1-10 kHz). An increase in sensitivity was detected from DAB 18-38. The lowest tested frequency (0.3 kHz) reached adult levels earlier than higher frequencies. No further improvement of auditory thresholds could be observed from DAB 38 (end of nutritional weaning) to DAB 42. Results were related to recent findings on the development of acoustical behavior and of the peripheral and central auditory system of tree shrews and other mammals.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D004432	Ear, Middle	The space and structures directly internal to the TYMPANIC MEMBRANE and external to the inner ear (LABYRINTH). Its major components include the AUDITORY OSSICLES and the EUSTACHIAN TUBE that connects the cavity of middle ear (tympanic cavity) to the upper part of the throat.	Tympanic Cavity,Tympanum,Middle Ear,Cavities, Tympanic,Cavity, Tympanic,Ears, Middle,Middle Ears,Tympanic Cavities,Tympanums
D000161	Acoustic Stimulation	Use of sound to elicit a response in the nervous system.	Auditory Stimulation,Stimulation, Acoustic,Stimulation, Auditory
D000367	Age Factors	Age as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or the effect of a circumstance. It is used with human or animal concepts but should be differentiated from AGING, a physiological process, and TIME FACTORS which refers only to the passage of time.	Age Reporting,Age Factor,Factor, Age,Factors, Age
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D000819	Animal Communication	Communication between animals involving the giving off by one individual of some chemical or physical signal, that, on being received by another, influences its behavior.	Animal Communications,Communication, Animal,Communications, Animal
D001307	Auditory Perception	The process whereby auditory stimuli are selected, organized, and interpreted by the organism.	Auditory Processing,Perception, Auditory,Processing, Auditory
D001309	Auditory Threshold	The audibility limit of discriminating sound intensity and pitch.	Auditory Thresholds,Threshold, Auditory,Thresholds, Auditory
D001522	Behavior, Animal	The observable response an animal makes to any situation.	Autotomy Animal,Animal Behavior,Animal Behaviors
D013216	Reflex, Startle	A complex involuntary response to an unexpected strong stimulus. The reaction involves physical movement away from the stimulus, MUSCLE CONTRACTION and limb flexion, BLINKING, and changes in HEART RATE, BLOOD PRESSURE, and RESPIRATION.	Startle Reaction,Acoustic Startle Reflex,Reflex, Moro,Startle Response,Moro Reflex,Reaction, Startle,Reactions, Startle,Reflex, Acoustic Startle,Response, Startle,Responses, Startle,Startle Reactions,Startle Reflex,Startle Reflex, Acoustic,Startle Responses