Much has been studied and written about plastic changes in the CNS of humans triggered by events such as limb amputation. However, little is known about the extent to which the original pathways retain residual function after peripheral amputation. Our earlier, acute study on long-term amputees indicated that central pathways associated with amputated peripheral nerves retain at least some sensory and motor function. The purpose of the present study was to determine if these functional connections would be strengthened or improved with experience and training over several days time. To do this, electrodes were implanted within fascicles of severed nerves of long-term human amputees to evaluate the changes in electrically evoked sensations and volitional motor neuron activity associated with attempted phantom limb movements. Nerve stimulation consistently resulted in discrete, unitary, graded sensations of touch/pressure and joint-position sense. There was no significant change in the values of stimulation parameters required to produce these sensations over time. Similarly, while the amputees were able to improve volitional control of motor neuron activity, the rate and pattern of change was similar to that seen with practice in normal individuals on motor tasks. We conclude that the central plasticity seen after amputation is most likely primarily due to unmasking, rather than replacement, of existing synaptic connections. These results also have implications for neural control of prosthetic limbs.
Ménière's ears display alterations in cervical and ocular vestibular evoked myogenic potentials tuning responses with changes in the latter being more prominent. These findings indicate that the disease process affects both the otolith organs but may have an enhanced effect on the utricle. We propose that this more dominant affect may relate to the anatomical configuration of the utricle.
This survey illustrates wide variation of current practice of intratympanic corticosteroid injection for ISSHL in Germany and Austria. In the absence of high-level evidence, knowing what current practice is allows clinicians to assess what they do against what their colleagues are doing, and if they do something very different, make them question their practice. Moreover, the obtained data will help to direct future clinical trials with the aim to compare the outcomes of more commonly used protocols.
Objective: To investigate the current practice of intratympanic steroid (ITS) injection for sudden sensorineural hearing loss (SSNHL) in the United Kingdom and link the data with data from the United States and continental Europe. Methods: A survey of 21 questions was distributed to members of the British Society of Otology using an online survey platform via ENT UK. Data obtained from UK otolaryngologists (n = 171) were integrated with previously published data from other countries, including the United States (n = 63) and continental Europe (n = 908). Results: In the United Kingdom, 62% of responding otolaryngologists use ITS injection for SSNHL, while 38% do not. Of those using ITS, 59% use it as first-line treatment, either using it in conjunction with oral steroids (51%) or using it as monotherapy (8%). Of those that use ITS, a majority (83%) use it as salvage therapy when primary treatment with systemic steroids has failed, and similar results are found in the continental Europe and US surveys. The most commonly used preparation is dexamethasone. Responses to questions regarding treatment regimes used are enlightening and show considerable variation in the treatment regimes used within and between countries. Conclusions: There is a wide variation in practice with regards to ITS for SSNHL hearing loss in the United Kingdom, United States, and continental Europe. In the absence of protocols or definitive guidance from published literature, knowledge of contemporary practice may help guide or encourage reevaluation of clinical practice and will help guide the design of future clinical trials.
Roadside bird mortality is a new environmental dimension in developing countries. With the recent increase in the number of high-speed cars and the simultaneous improvement of roads in India, bird-car strikes and the resultant bird mortality are becoming important. To know how many species frequent roads in Punjab and thus may be prone to be killed by fast vehicles, we censused birds along 420 km of roads of different widths and traffic volumes from a vehicle moving at 50–60 km per hour. We also counted birds along transects c. 1 km away from roads, for comparison.In all, 35 species of birds were recorded on the road proper or within 3 m of either edge. Common Myna (Acridotheres trisitis) was the most abundant species (34.8% of all birds), followed by House Sparrow (Passer domesticus) (29.5%), Ring Dove (Streptopelia decaocto) (13.1%), and House Crow (Corvus splendens) (9.7%). These four species together accounted for c. 87% of the total of all bird species. The off-road community consisted of 68 species. The species-richness of granivorous, insectivorous, omnivorous, and some other birds, was less on or near roads than in the off-road transects, but within each community, species having different feeding habits were in similar proportions. About 93% of the total birds on or near roads (as against 66% off-road) were either granivorous or omnivorous.Our results suggested that granivorous birds are attracted, but insectivorous and other birds are repelled, by roads. Omnivores were equally abundant on and off roads. Food (such as spilled grain) seemed to be the main factor attracting birds to roads. Species diversity and equitability of the bird community on roads (1.82 and 0.51, respectively) were less than those off-roads (3.11 and 0.74, respectively). Wider roads had lower species-diversity and equitability, probably because of the greater volume of traffic on them compared with narrower roads. Species richness and bird abundance seemed not to be affected by roadwidth. Bird mortality on roads is discussed, along with the possibility of roads acting as “ecological traps” for foraging birds.
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