Notes
A collection of fragments of understanding in the pursuit of deeper questions.
Contents
- Computational Vision
- Introduction to Data Science
- Translational Neuromodeling
- Deep Learning in Artificial & Biological Neuronal Networks
- Introduction to Neuroinformatics
- Intro to Neuroscience
- Systems Neuroscience
- Readings in Neuroinformatics
- Neurobiology of Consciousness
- Econometrics
- Principles of Finance
- Big Data & Databases
- Game Theory
- Intro to Blockchain
- Marketing Analytics
- Financial Accounting
- Fundamentals of Computer Science
- Foundamentals of Information Technology Law
- Statistics
- Computer Programming
- Macroeconomics
- EU Information Law & Data Economy
- Advanced Mathematics & Statistics
- Principles of Management
- Mathematics
- Microeconomics
The Fascination of Hearing
Prologue: The Fascination of Hearing The vibration of an object (e.g., tuning fork) causes changes in air pressure. Hence, acoustic sound waves can be described as fluctuations in air pressure due to compression and rarefaction of air molecules. The auditory system transforms sound waves into distinct patterns of neural activity, which are then integrated with information from other senses (and cognition) to guide behavior and promote communication. The auditory system is not only essential for speech, but also for music, emotion recognition, sound localization, etc.
- Frequency range of hearing across species.
- Sound Localization:
- Having two ears (instead of one) is important for sound localization.
- Due to the perception of interaural time (ITD) and level (ILD) differences between the two ears we are able to localize sound sources in the environment.
- Sound localization in the horizontal plane (azimuth) is based on ITD and ILD, while sound localization in the vertical plane is based on spectral filtering by ears, head and shoulders.
- Hearing enables:
- To perceive and identify object from far away, vision doesn't.
- To perceive sounds from all around the body with an angle of 360 degrees (vision only 180 degrees).
- To maps the sound in space and to identify the spatial location of objects.
- To recognize emotional states (e.g., speech prosody, sad, happy, fear, etc.)
- Complex human faculties like music and language.
However, there is also a "dark side" of hearing such as hearing loss, tinnitus, amusia, etc.
The Basic Building Blocks of Acoustic Signals: Air Pressure and Waves
- Soundwave as variation in air pressure.
- Complex sound waveform: Each complex signal can be decomposed into sine and cosine waves.
- Each oscillation can be described in terms of amplitude and frequency. Frequency (Hz) = number of periods (cycles) per second.
Sound Processing Along the Hierarchy of the Auditory System
- Peripheral Auditory System: Outer, Middle and Inner Ear.
- Central Auditory System: Auditory Brainstem and Cortex.
