• MeSH
• Congresses as Topic MeSH
• Hearing Disorders MeSH
• Auditory Cortex physiopathology   physiology   MeSH
• Publication type
• Collected Work MeSH
• Geographicals
• Portugal MeSH

• Conspectus
• Patologie. Klinická medicína
• NML Fields
• otorinolaryngologie
• neurovědy

• MeSH
• Auditory Cortex physiology   MeSH
• Publication type
• Congress MeSH

• Conspectus
• Lékařské vědy. Lékařství
• NML Fields
• otorinolaryngologie
• fyziologie

• MeSH
• Convulsants MeSH
• Dogs MeSH
• Check Tag
• Dogs MeSH

• MeSH
• Behavior MeSH
• Evoked Potentials MeSH
• Cats MeSH
• Cerebral Cortex physiology   MeSH
• Check Tag
• Cats MeSH

• MeSH
• Evoked Potentials MeSH
• Rats MeSH
• Tectum Mesencephali MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Animals MeSH

• MeSH
• Audiometry MeSH
• Auditory Diseases, Central MeSH
• Prosthesis Implantation MeSH
• Cochlear Implants MeSH
• Brain Stem MeSH
• Neurofibromatoses MeSH
• Auditory Cortex MeSH
• Publication type
• Congress MeSH

• Conspectus
• Patologie. Klinická medicína
• NML Fields
• otorinolaryngologie
• otorinolaryngologie

• MeSH
• Afferent Pathways physiology   MeSH
• Cats MeSH
• Cerebral Cortex physiology   MeSH
• Brain Stem physiology   MeSH
• Check Tag
• Cats MeSH

Age-related hearing loss (presbycusis) is caused mainly by the hypofunction of the inner ear, but recent findings point also toward a central component of presbycusis. We used MR morphometry and diffusion tensor imaging (DTI) with a 3T MR system with the aim to study the state of the central auditory system in a group of elderly subjects (>65years) with mild presbycusis, in a group of elderly subjects with expressed presbycusis and in young controls. Cortical reconstruction, volumetric segmentation and auditory pathway tractography were performed. Three parameters were evaluated by morphometry: the volume of the gray matter, the surface area of the gyrus and the thickness of the cortex. In all experimental groups the surface area and gray matter volume were larger on the left side in Heschl's gyrus and planum temporale and slightly larger in the gyrus frontalis superior, whereas they were larger on the right side in the primary visual cortex. Almost all of the measured parameters were significantly smaller in the elderly subjects in Heschl's gyrus, planum temporale and gyrus frontalis superior. Aging did not change the side asymmetry (laterality) of the gyri. In the central part of the auditory pathway above the inferior colliculus, a trend toward an effect of aging was present in the axial vector of the diffusion (L1) variable of DTI, with increased values observed in elderly subjects. A trend toward a decrease of L1 on the left side, which was more pronounced in the elderly groups, was observed. The effect of hearing loss was present in subjects with expressed presbycusis as a trend toward an increase of the radial vectors (L2L3) in the white matter under Heschl's gyrus. These results suggest that in addition to peripheral changes, changes in the central part of the auditory system in elderly subjects are also present; however, the extent of hearing loss does not play a significant role in the central changes.

• MeSH
• Auditory Diseases, Central pathology   MeSH
• Adult MeSH
• Humans MeSH
• Magnetic Resonance Imaging MeSH
• Young Adult MeSH
• Nerve Fibers, Myelinated pathology   MeSH
• Presbycusis pathology   physiopathology   MeSH
• Aged MeSH
• Auditory Pathways pathology   MeSH
• Auditory Cortex pathology   MeSH
• Aging pathology   physiology   MeSH
• Diffusion Tensor Imaging MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Young Adult MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

Spontaneous activity of cortical neurons exhibits alternative fluctuations of membrane potential consisting of phased depolarization called "up-state" and persistent hyperpolarization called "down-state" during slow wave sleep and anesthesia. Here, we examined the effects of sound stimuli (noise bursts) on neuronal activity by intracellular recording in vivo from the rat auditory cortex (AC). Noise bursts increased the average time in the up-state by 0.81+/-0.65 s (range, 0.27-1.74 s) related to a 10 s recording duration. The rise times of the spontaneous up-events averaged 69.41+/-18.04 ms (range, 40.10-119.21 ms), while those of the sound-evoked up-events were significantly shorter (p<0.001) averaging only 22.54+/-8.81 ms (range, 9.31-45.74 ms). Sound stimulation did not influence ongoing spontaneous up-events. Our data suggest that a sound stimulus does not interfere with ongoing spontaneous neuronal activity in auditory cortex but can evoke new depolarizations in addition to the spontaneous ones.

• MeSH
• Acoustic Stimulation methods   MeSH
• Rats MeSH
• Neurons physiology   MeSH
• Rats, Sprague-Dawley MeSH
• Auditory Pathways cytology   physiology   MeSH
• Evoked Potentials, Auditory physiology   MeSH
• Auditory Cortex cytology   physiology   MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Research Support, Non-U.S. Gov't MeSH
• Comparative Study MeSH

Hearing loss, presbycusis, is one of the most common sensory declines in the ageing population. Presbycusis is characterised by a deterioration in the processing of temporal sound features as well as a decline in speech perception, thus indicating a possible central component. With the aim to explore the central component of presbycusis, we studied the function of the auditory cortex by functional MRI in two groups of elderly subjects (>65 years) and compared the results with young subjects (

• MeSH
• Acoustic Impedance Tests MeSH
• Audiometry, Pure-Tone MeSH
• Audiometry, Speech MeSH
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Magnetic Resonance Imaging MeSH
• Brain Mapping MeSH
• Presbycusis physiopathology   radiography   MeSH
• Aged MeSH
• Auditory Cortex physiopathology   radiography   MeSH
• Auditory Threshold MeSH
• Aging * MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH