Abnormal cavitations of the central nervous system generally are named by using the idiom “syrinx-” and they occur most frequently in the spinal cord as syringomyelia. The underlying event usually is a malformation of the central nervous system caused by arrested development before gray and white matter have completed differentiation.’ Acquired syringomyelia as a post-traumatic event also has b...

Birdsong has developed into one of the important models for motor control of learned behaviour and shows many parallels with speech acquisition in humans. However, there are several experimental limitations to studying the vocal organ - the syrinx - in vivo. The multidisciplinary approach of combining experimental data and mathematical modelling has greatly improved the understanding of neural ...

BACKGROUND Singing in songbirds is a complex, learned behavior which shares many parallels with human speech. The avian vocal organ (syrinx) has two potential sound sources, and each sound generator is under unilateral, ipsilateral neural control. Different songbird species vary in their use of bilateral or unilateral phonation (lateralized sound production) and rapid switching between left and...

The bilateral simultaneous generation of sound in some oscine songbirds leads to complex sounds that cannot be described in terms of a superposition of the isolated sources alone. In this work, we study the appearance of complex solutions in a model for the acoustic interaction between the two sound sources in birdsong. The origin of these complex oscillations can be traced to the nonlinear mod...

The study of dynamical systems has proven to be an invaluable tool for understanding how songbirds sing. A very simple nonlinear oscillator model that is similar to a springmass system can shed a light onto the physics of the avian vocal organ, the syrinx. Furhermore, dynamic variation of the system parameters via temporal hierarchy gives rise to highly precise modeling of birdsongs.

A neurogenic bladder is seldom described as the first manifestation of syringomyelia. A patient is reported with an extensive syrinx along the entire spinal cord and a Chiari type I malformation, who experienced dysaesthesia and weakness during shooting practice and presented with urinary retention.

Greater sage-grouse, Centrocercus urophasianus, have been a model system in studies of sexual selection and lek evolution. Mate choice in this species depends on acoustic displays during courtship, yet we know little about how males produce these sounds. Here we present evidence for previously undescribed two-voiced sound production in the sage-grouse. We detected this ;double whistle' (DW) usi...