Jan Siegborn

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Twenty-seven adult cats were used to study the central projection of the horizontal ampullar nerve and the utricular nerve using transganglionic transport of HRP. The nerve to be investigated was exposed transtympanally, cut, and a capsule containing 50% HRP applied to the proximal stump for one hour; 2-8 days later the animals were perfused. Frozen serial(More)
The brainstem projections of the ampullar nerves from the vertical semicircular canals, the anterior (AAN) and the posterior ampullar nerve (PAN), were studied in adult cats using the transganglionic horseradish peroxidase (HRP) method. Each nerve was exposed in three experiments. Two animals in each group had labeling which allowed detailed mapping. From(More)
The brainstem projection of the saccular nerve was investigated by transganglionic tracing with horseradish peroxidase in the cat. The labeled fibers were located most caudally and laterally (dorsolaterally) in the vestibular nerve root. This was unique when compared with the locations of the fibers from the nerves of the other vestibular-end organs that(More)
The effect of heat stress and balanced pressure breathing during G (PBG) on G-endurance was investigated. Ten fighter pilots wearing anti-G-suits with increased bladder coverage were warmed to 38.2 degrees C and exposed to 15-s periods at 4.5 and 7 G in a heated human centrifuge gondola until exhaustion during PBG and normal breathing (NB). During both NB(More)
For the experiments 39 cats were used. Selective sectioning of either the anterior or the posterior vertical ampullar nerves was performed bilaterally. Additionally in some cats the utricular nerves were cut, or the saccule extirpated on one or both sides. The otolith organs were stimulated by tilting around the bitemporal axis of the animals. Bilateral(More)