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Overall results confirm the improvement in frequency discrimination performance around the cutoff frequency in subjects with steeply sloping hearing loss. This effect does not appear to depend on the pattern of the hearing loss, as it can be observed in subjects with low-frequency, as well as notched hearing losses. Our findings, pointing to the steepness of the hearing loss and the presence of dead cochlear regions as the most important factors of the local DLF enhancement effect, are consistent with an interpretation in terms of injury-induced central auditory reorganization. The reversal of this plasticity after amplification may open some interesting therapeutic horizons. In particular, the benefit of hearing amplification might be conditioned by the occurrence of a secondary plasticity. This issue needs to be investigated by further research.

There is considerable capacity for plasticity in the mature auditory brain stem and plastic changes can be evoked by the change in activity resulting from profound deafness. There are deafness related changes in transmitters and receptors with resulting changes in inhibition and activity that can effect auditory processing. An understanding of the underlying mechanisms of plasticity, with gene microarray results pointing to a number of regulatory pathways, could help in development of interventions to influence plasticity. Such interventions should be helpful to provide the best circumstances for return of hearing with cochlear prostheses following deafness as well as for management of clinical problems resulting from the plasticity of partial deafness and central tinnitus.

Subjects can differentiate between upward and downward moving spectral envelope patterns within a circumscribed range of spectral profiles and drift rates. The range for accurate performance appears to be consistent with spectral resolution in the periphery and the receptive field characteristics found in auditory cortex. The presence of multiple peaks in the spectral profile helps discrimination at low sweep rates, while at higher rates discrimination is better if only one moving peak is present. In conclusion, these experiments have shown that subjects are sensitive to the spectrotemporal envelope of stimuli in the absence of meaningful fine structure, within the range of spectral peak densities and sweep rates characteristic of speech.

Since negotiators are decision-makers, understanding a negotiation requires a deep understanding of the negotiators’ decisions. As Hayek suggests, the theoretical foundations in this chapter address decision-making and preferences from the viewpoint of different disciplines. The origin of preferences and their stability over time varies widely across fields: Economists, for example, usually assume preferences to be an underlying property of any individual and to be stable over time. If an agent’s choice changes over time, then either the production technology available or the information at hand have changed—preferences do not. This widely used perspective is most notably vindicated by Stigler and Becker (1977) in a seminal paper arguing against the assumption of changing preferences and it is outlined in several microeconomic textbooks, e.g. Kreps (1990), Varian (1992), Mas-Colell, Whinston, and Green (1995).

The present study indicates that the neuro-specific co-transporter KCC2 is expressed abundantly throughout the IC. The postnatal expression pattern of KCC2 is upregulated in the IC as well as that in the neocortex, the hippocampus and the cerebellum. Considering the importance of this co-transporter on controlling auditory function, further studies are needed in all aspects including the neuronal maturation and the switching mechanisms.

Presented results show that in adult congenitally deaf cats there is: a local desynchronization of inputs within adjacent synapses, an interlayer desynchronization of inputs to different layers in cortex, and possibly also a decreased inhibition in layer IV and III.

Since negotiators are decision-makers, understanding a negotiation requires a deep understanding of the negotiators’ decisions. As Hayek suggests, the theoretical foundations in this chapter address decision-making and preferences from the viewpoint of different disciplines. The origin of preferences and their stability over time varies widely across fields: Economists, for example, usually assume preferences to be an underlying property of any individual and to be stable over time. If an agent’s choice changes over time, then either the production technology available or the information at hand have changed—preferences do not. This widely used perspective is most notably vindicated by Stigler and Becker (1977) in a seminal paper arguing against the assumption of changing preferences and it is outlined in several microeconomic textbooks, e.g. Kreps (1990), Varian (1992), Mas-Colell, Whinston, and Green (1995).

The results of the present study document that a significant low-frequency hearing loss occurrs as early as in one-month-old F344 rats and results in a lack of recordable TEOAEs and in the absence of DPOAEs at low frequencies. The low-frequency defect, which preceeds the later occurring high-frequency hearing loss, is probably not connected with the degeneration of hair cells or specific age-related hearing loss genes, but can be related to more general genetic mutations present in this rat strain.

Subjects can differentiate between upward and downward moving spectral envelope patterns within a circumscribed range of spectral profiles and drift rates. The range for accurate performance appears to be consistent with spectral resolution in the periphery and the receptive field characteristics found in auditory cortex. The presence of multiple peaks in the spectral profile helps discrimination at low sweep rates, while at higher rates discrimination is better if only one moving peak is present. In conclusion, these experiments have shown that subjects are sensitive to the spectrotemporal envelope of stimuli in the absence of meaningful fine structure, within the range of spectral peak densities and sweep rates characteristic of speech.

The results of the present study document that a significant low-frequency hearing loss occurrs as early as in one-month-old F344 rats and results in a lack of recordable TEOAEs and in the absence of DPOAEs at low frequencies. The low-frequency defect, which preceeds the later occurring high-frequency hearing loss, is probably not connected with the degeneration of hair cells or specific age-related hearing loss genes, but can be related to more general genetic mutations present in this rat strain.