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Pleasurable emotional response to music: A case of neurodegenerative generalized auditory agnosia
Published in Howard J. Rosen, Robert W. Levenson, Neurocase, 2020
Brandy R. Matthews, Chiung-Chih Chang, Mary De May, John Engstrom, Bruce L. Miller
A brief review of the nosology of auditory agnosia is pertinent to our description of this patient. Generalized auditory agnosia refers to a rare condition in which subjects demonstrate impairment in the ability to recognize sounds in spite of adequate hearing as measured by standard audiometry (Mendez, 2001). Bitemporal cortical lesions have been reported as the neuroanatomic substrate of the condition, most frequently as the result of cerebrovascular disease (Vignolo, 2003), but also in association with neurodegeneration (Pinard et al., 2002), herpes encephalitis (Kaga et al., 2003), and traumatic brain injury (Hattiangadi et al., 2005). Lesions with a similar distribution involving the primary auditory cortex (BA 41) and auditory association cortex (BA 42 & 22) bilaterally may also result in cortical deafness, a distinct condition that yields an abnormal pure tone audiogram and therefore impairs the perception of sounds preceding the assignment of their meanings (Mendez & Geehan, 1988; Szirmai et al., 2003).
Nervous system
Published in David Sturgeon, Introduction to Anatomy and Physiology for Healthcare Students, 2018
The final lobe of the cerebrum is the temporal lobe which is separated from the frontal and parietal lobes by the lateral sulcus (Sylvian fissure). It consists of the primary auditory cortex, the auditory association area and a number of limbic system structures including the hippocampus (Figure 12.10). The primary auditory cortex receives sound information in terms of pitch, rhythm and volume from the inner ear via the auditory nerve. The auditory association area interprets and translates these noises as speech, music or other familiar/unfamiliar sounds. Memories of sounds heard in the past are also stored in the temporal lobe, and we observed earlier in the chapter that the hippocampus is closely associated with the formation and retrieval of memories. The temporal lobe also seems to play an important role in face and object recognition and speech and language processes (Wernicke’s area is situated where the temporal and parietal lobes meet). Damage to the temporal lobe can result in a condition called agnosia where individuals are unable to recognise common objects, sounds, shapes or smells. The type of agnosia is dependent on which part of temporal lobe (or elsewhere) has been affected. For example, auditory agnosia often occurs following damage to the superior temporal lobe whereas visual agnosia occurs as a result of damage to the middle-inferior temporal lobe or posterior occipital lobe.
Neuropharmacologic considerations in the treatment of vegetative state and minimally conscious state following brain injury
Published in Mark J. Ashley, David A. Hovda, Traumatic Brain Injury, 2017
Coleman et al.29 used fMRI to determine if patients in vegetative state retain some aspects of language comprehension. Indeed, some evidence of activation of the primary auditory cortex was noted in response to spoken language. However, the authors conceded that these findings did not imply actual language comprehension or consciousness. For conscious awareness of speech to occur, language must be “heard” in the auditory primary cortex, recognized in the auditory association cortex, and finally comprehended in Wernicke’s area. Laureys et al.30 found that, although auditory primary cortices are activated by auditory stimulation in the patient in vegetative state, the higher order association areas were not. They concluded that these functional disconnections preclude the integrated processing necessary for understanding, reflection, and awareness. Consistent with this view is the finding of improvement in disrupted connections between thalamic nuclei and their projections to the prefrontal and cingulate cortical regions in patients who have recovered consciousness.
Gap detection responses modelled using the Hill equation in adults with well-controlled HIV
Published in International Journal of Audiology, 2023
Christopher E. Niemczak, Christopher Cox, Gevorg Grigoryan, Gayle Springer, Abigail M. Fellows, Peter Torre, Howard J. Hoffman, Jay C. Buckey, Michael W. Plankey
While peripheral mechanisms in the cochlea encode temporal aspects of sound, the auditory cortex also contributes to auditory temporal processing (Eggermont 2000; Rupp et al. 2002). For example, Bertoli, Smurzynski, and Probst (2002) compared psychoacoustic gap detection thresholds with auditory electrophysiological responses evoked by varying gap durations. They found evident mismatch negativity responses when a silent gap within a 1.0-kHz sinusoid was approximately 9 ms as compared with behavioural gap detection thresholds at approximately 6 ms in the same listeners. Additionally, Rupp, Gutschalk et al. (2002) found evidence from neuromagnetic recording of middle latency responses that showed the primary auditory cortex can resolve gaps as small as 3 ms. While the differences in results were most likely due to different recording techniques, it is evident that the primary auditory cortex plays a central role in auditory temporal processing.
Obstetric Brachial Plexus Palsy: Can a Unilateral Birth Onset Peripheral Injury Significantly Affect Brain Development?
Published in Developmental Neurorehabilitation, 2020
Egmar Longo, Ryota Nishiyori, Theresa Cruz, Katharine Alter, Diane L. Damiano
Similar to our overall results, others have showed differences between OBPP and healthy controls, specifically significant cortical volume loss likely due to decreased fiber number and/or size from primary motor region in the hemisphere contralateral to the injured arm when compared with healthy controls.43 Given what we know about enhanced plasticity in the perinatal and early-childhood “critical period”18, it is not surprising that we see significant cortical changes in the primary motor and supplementary areas of young people with OBPP. This observation is similar to fMRI studies in individuals with acquired unilateral lower-limb amputation, providing evidence that peripheral nerve injury even in adults influences brain plasticity.46 Children blind from birth have shown dramatic cortical changes with the occipital lobes basically repurposed to respond to auditory or tactile information.47 Similarly, children deaf from birth show neuroplastic changes in the primary auditory cortex.48 Studies of sensory loss demonstrate that experience can change the sensory modality to which a cortical area responds, but the extent to which cortical regions can truly change their function remains debated.49,50
Impaired auditory processing and neural representation of speech in noise among symptomatic post-concussion adults
Published in Brain Injury, 2019
Kathy R. Vander Werff, Brian Rieger
Evidence has accumulated that a significant minority of individuals experience persistent long-term deficits following mild traumatic brain injury (mTBI) or concussion (1–4). Among the chronic problems, studies have documented auditory dysfunction following both non-blast and blast-related mTBI. Despite the fact that few of these individuals have hearing outside the normal range on a clinical audiogram, a significant percentage report difficulty understanding speech in background noise as well as difficulty on other complex auditory tasks, such as understanding rapid speech or detecting small gaps in noise (5–13). Difficulties with these tasks may result from damage to structures in the central auditory pathway from the brainstem to the primary auditory cortex may be vulnerable to mTBI, including auditory brainstem nuclei, structures in the left temporal lobe, pathways between the thalamus and primary auditory cortex, the planum temporale, and the corpus callosum (14–16). Identifying whether there is electrophysiological evidence of changes in how speech information is represented along the central auditory pathway and whether behavioral deficits correlate with these neural representations is of interest to better understand the long-term auditory consequences of mTBI.