Shayan Ahmed, Jamia Millia Islamia, New Delhi
Basic brain processes include locating and recognising sensory items while navigating the environment. The ability to traverse the environment requires knowledge of the location of sensory elements and the identification of their contemporaneous behavioural relevance. The auditory system computes spatial information in the brain depending on the position of the acoustic signals relative to the observer. Thus, the auditory pathway is considered to be egocentric throughout. This notion is primarily based on research in animals that were either sedated and were passively listening, i.e., without the ability to move or listen selectively. Auditory neurons use angle-specific variations in sound characteristics between the ears to compute azimuthal spatial information. A preponderance of wide neuronal tuning to contralateral sound-source locations has been documented from the brainstem to the primary auditory cortex (A1). Auditory neuronal spatial tuning is considered egocentric by default. While self-movement continually changes the egocentric sound-source location, the impression of source position stays fixed in relation to world coordinates, i.e., it is allocentric.
A recent study shows that a small fraction of neurons in A1 have entirely allocentric representation. However, because the subjects were passively exposed to sounds, the stimuli and related sources in this investigation were task-irrelevant. But, active sensing and task engagement/stimulus relevance are also important factors in A1 neural coding. Thus, it’s still a mystery how sound sources are represented in normal sensing behaviour. In the study in discussion, the spatial tuning in A1 during active sensing was discovered to vary significantly from the canonically expected egocentric representation. The majority of neurons had temporally diversified spatial tuning that varied depending on the sound source. Artificial neural network decoding revealed that these unique tuning characteristics yield spatiotemporally coexistent information regarding instantaneous source angles and angle-independent source identification. The novel neuronal calculations appear to be well adapted to recognising and tracking individual sound sources in the surroundings while having self-movement.
Also read: Phenotypic Imaging of Nephroblastoma Cancer cells
References:
- Amaro, D., Ferreiro, D. N., Grothe, B., & Pecka, M. (2021). Source identity shapes spatial preference in primary auditory cortex during active navigation. bioRxiv. https://doi.org/10.1016/j.cub.2021.06.025
About author:
Shayan Ahmed is currently pursuing a Master of Science degree in Microbiology from the Department of Biosciences, Jamia Millia Islamia, New Delhi. His area of research interest lies in antibiotic resistance and associated molecular mechanisms. His recent work was focused on understanding colistin resistance patterns in the environment, particularly in water bodies.
- The Corrosion Prediction from the Corrosion Product Performance
- Nitrogen Resilience in Waterlogged Soybean plants
- Cell Senescence in Type II Diabetes: Therapeutic Potential
- Transgene-Free Canker-Resistant Citrus sinensis with Cas12/RNP
- AI Literacy in Early Childhood Education: Challenges and Opportunities
Forensic Anthropology Ancestry: Again, on Threshold of Racism
Saptaparna Dasgupta, Bennett University Research on forensic anthropology has risen as a key factor in the estimation of ancestry. Despite forensic anthropology being controversial for use, ancestry still rules as a crucial parameter. It is used for the estimation of the socio racial categories of law enforcement, anticipated via cranial variation. To examine human physical […]