Q3: What relevant investigations would you request? Routine blood analysis including erythrocyte sedimentation rate, thyroid function tests, and B12; lateral cervical spine radiography and magnetic resonance imaging (MRI) of cervical spine. This woman’s MRI scans (see figs 1 and 2) revealed a dilated syrinx extending from C2–T3 with characteristic septation in the lower cervical region. There w...

A case of a Chiari malformation with an extraordinarily thick occipital bone is described. The thick occipital bone might make the posterior fossa narrow with consequent herniation of the cerebellar tonsils to the foramen magnum and formation of a syrinx. At dural plasty, well-developed marginal and occipital sinuses should be deliberately handled with the preservation of normal venous drainage...

A 31-year-old woman presented with worsening numbness and pain in the arms and chest. Neurological findings at admission were decreased pain sensation and temperature sensation in the arms and chest. Magnetic resonance demonstrated a large cervical syrinx from the level of C4 to Th4 associated with Chiari I malformation. Occipital craniectomy and C1 laminectomy were performed for foramen magnum...

The songbird vocal organ, the syrinx, is composed of two sound generators, which are independently controlled by sets of two extrinsic and four intrinsic muscles. These muscles rank among the fastest vertebrate muscles, but the molecular and morphological foundations of this rapid physiological performance are unknown. Here we show that the four intrinsic muscles in the syrinx of male European ...

Anatomy and Physiology The avian respiratory tract is substantially different and much more efficient compared to mammals. The upper respiratory tract in birds is characterized by an extensive infraorbital sinus, a choana, and a larynx that is lacking an epiglottis. In addition, the larynx is not used for voice production in birds; instead, this occurs in the syrinx. The trachea in birds is com...

MR imaging was performed to determine the cause of the onset of new neurologic symptoms in five patients who had previously undergone surgical excision of extramedullary masses. Syringomyelia and the absence of recurrent or residual lesions were documented in all cases. Three patients showed long cysts (multiseptated in two and smooth in one) with low signal intensity on both T1- and T2-weighte...

Learned behaviors require coordination of diverse sensory inputs with motivational and motor systems. Although mechanisms underlying vocal learning in songbirds have focused primarily on auditory inputs, it is likely that sensory inputs from vocal effectors also provide essential feedback. We investigated the role of somatosensory and respiratory inputs from vocal effectors of juvenile zebra fi...

The syrinx of oscine birds ("true songbirds") is a double vocal organ, and each side has generally been presumed to function independently under separate neural control during phonation. A significant counterexample is demonstrated here in the production of a common vocalization by the black-capped chickadee (Parus atricapillus), in which the 2 acoustic sources of the syrinx interact in a nonli...

Adult zebra finch song is irreversibly altered when birds are deprived of correct feedback by deafening or denervation of the syrinx. To clarify the role of feedback in song maintenance, we developed a reversible technique to distort vocal output without damaging the auditory or vocal systems. We implanted flexible beads adjacent to the syrinx to alter its biomechanics. Immediate song aberratio...