Cognitive psychology l7 spring2019
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The document discusses the role of the hearing brain. It constructs an internal model of the world from sensory information and experience in order to interpret and act on sounds. The hearing brain extracts consistent features from varying sensory input and actively interprets what is heard. It also discusses how auditory information is processed from the cochlea to primary and secondary auditory cortex and specialized regions involved in voice perception, speech, music and amusia.
Cognitive psychology l7 spring2019
- 1. Cognitive Psychology Lesson 7 - Spring 2019 The hearing brain Professor Valentina Bazzarin USAC Reggio Emilia
- 2. The hearing brain The human auditory system is able to detect a huge range of changes in air pressure, from around 0,00002 to over 100 Pascals. However the role of hearing brain is not merely to detect such changes. Its role consists in constructing an internal model of the world that can be interpreted and acted upon. Sounds originates from motion or vibration of an object
- 3. AIVA, an artificial intelligence that has been trained in the art of music composition https://www.ted.com/talks/pierre_barre au_how_ai_could_compose_a_personalized _soundtrack_to_your_life
- 4. Sensory information Sensory experience This model is constructed not only using sensory information but also from previous sensory experience. The hearing brain extracts “constancy” out of an infinitely varying array of sensory input and it will actively interpret the sensory input.
- 7. Pure tones Pitch Loudness Pure tones: sounds with a sinusoid waveform (when pressure change is plotted against time). Pitch: the perceived property of sounds that enables them to be ordered from low to high. Loudness: the perceived intensity of the sound.
- 8. Frequency Fundamental frequency The lowest frequency component of a complex sound that determines the perceived pitch. Missing fundamental phenomenon If the fundamental frequency of a complex sound is removed, then the pitch is not perceived to change (the brain reinstates it).
- 9. Timbre Timbre The perceptual quality of a sound enables us to distinguish between different musical instruments
- 10. Does Music Change a Child's Brain? https://www.youtube.com/watch?v=M2sqXbwlaWw http://www.nbcnews.com/id/28423422/ns/health-he alth_care/t/cant-hear-holiday-parties-blame-your-br ain/
- 11. From ear to brain Cochlea: part of the inner ear that converts liquid born sound into neural impulse Basilar membrane: A membrane within the cochlea containing tiny hair cells linked to neural receptors. Primary auditory cortex: the main cortical area to receive auditory-based thalamic input. Belt and parabelt regions: parts of secondary auditory cortex Tonotopic organization: orderly mapping between sound frequency and position on cortex
- 12. Cognitive musicology Cognitive musicology is a branch of cognitive science concerned with computationally modeling musical knowledge with the goal of understanding both music and cognition (source wikipedia)
- 14. Basic processing of auditory information Sparse scanning: in fRMI a short break in scanning to enable sounds to be presented in relative silence. Head-related transfer function (HRTF): an internal model of how sounds get distorted by the unique shape of one’s own ears and head. https://www.youtube.com/watch?v=IJ7dCkWd PC0
- 15. Planum temporale Planum temporale: A part of auditory cortex (posterior to primary auditory cortex) that integrates auditory information with non auditory information, for example to enable sounds to be separated in space.
- 16. Music perception http://jakemandell.com/tonedeaf/
- 17. Amusia Amusia: an auditory agnosia in which music perception is affected more than the perception of other sounds. Congenital amusia (tone deafness): a developmental difficulty in perceiving pitch relationship.
- 18. Function of music Function of music: Pinker (1977) argued that language was the precursor to music and the latter does not have an adaptive function.
- 20. Voice perception Voice, like faces, convey a large amount of socially relevant information about the people around us. It is possible to someone’s sex, size, age and mood from their voice. Physical changes related to sex, size and age affect the vocal apparatus in systematic ways.
- 21. Speech perception Pure word deafness: type of auditory agnosia in which patients are able to identify environmental sounds and music but not speech Spectrogram: plots the frequency of sound (on the Y-axis) over time (on the X-axis) with the intensity of the sound represented by how dark it is
- 22. Key concepts (1/2) ● Hearing involves extracting features out of the sensory signal that may be useful for segregating the input into different “objects”; ● Cells within the secondary auditory cortex may have different degrees of specialization for the content of the sound (what) Vs the location of the sound (where) → dorsal (where) / ventral (what) pathway in the temporal lobes (left for speech); ● Music perception involves a number of different mechanism and they have partially separate neural substrates as revealed by fMRI and lesion-based studies; ● Evidences of a specialized region in the (right) temporal lobe that is specialized for the recognition of voices
- 23. Key concepts (2/2) ● Speech recognition involves extracting categorical information from sensory input that can vary infinitely. This may be achieved via acoustic processing and possibly via motor processing; ● Speech recognition (and speech repetition) may involve both a ventral “what” route and a dorsal “how” route for unfamiliar words and verbatim repetition (possibly corresponding to the use of the “articulatory loop”)