Biomedical subjects

Timothy D Griffiths

Publications and source records attributed to Timothy D Griffiths.

22 records · Page 2Linked to original sources

PubMed2002

Perception of sound-source motion by the human brain.

We assessed the human brain network for sound-motion processing using the same virtual stimulus in three independent functional imaging experiments. All experiments show a bilateral posterior network of activation, including planum temporale (PT) and parieto-temporal operculum (PTO). This was demonstrated in contrasts between sound movement and two control conditions: externalized stationary stimuli (in the midline or to the side of the head) and midline sounds within the head with similar spectro-temporal structure. We suggest specific computational mechanisms in PT for disambiguation of the intrinsic spectro-temporal features of a sound and the spectro-temporal effect of sound movement. The results support the existence of a posteriorly directed temporo-parietal pathway for obligatory perceptual processing of sound-source motion.

Adult↗

PubMed2002

The planum temporale as a computational hub.

It is increasingly recognized that the human planum temporale is not a dedicated language processor, but is in fact engaged in the analysis of many types of complex sound. We propose a model of the human planum temporale as a computational engine for the segregation and matching of spectrotemporal patterns. The model is based on segregating the components of the acoustic world and matching these components with learned spectrotemporal representations. Spectrotemporal information derived from such a 'computational hub' would be gated to higher-order cortical areas for further processing, leading to object recognition and the perception of auditory space. We review the evidence for the model and specific predictions that follow from it.

Algorithms↗

PubMed2002

Central auditory pathologies.

This chapter considers specific deficits in auditory processing ('negative' disorders) due to neurological conditions and 'positive' disorders of central auditory processing caused by abnormal activity in central auditory mechanisms. Recent work focuses on the assessment of auditory processing in disorders that are not specifically auditory. In this case, auditory measurement may provide a 'window' into the condition.

Audiometry, Pure-Tone↗

PubMed2002

Central auditory processing disorders.

Central auditory processing is essential for the perception of speech, environmental sounds and music, and may be deranged in two ways. Lesions of the ascending auditory pathway or cortex can produce deficits. Abnormal activity of the central auditory system is becoming increasingly recognized in disorders such as tinnitus. Recent work has investigated sound processing by the unconscious brain; such investigations may provide a 'window' into residual brain function and prognosis.

Agnosia↗