Upcoming events (January 2011)
This spring I will be teaching a Harvard Mind Brain and Behavior Initiative seminar entitled "Music, Mind ,and Brain" (MBB91). My newly revamped website will include study materials from that course and some discussion of topics in the psychology of music.
Site update: December 6, 2011
currently updating this website and preparing to migrate it to a more
stable server (please be patient, hopefully these changes will be
implemented this week). Here is a link to the new website.
I want to improve the overall organization of the site and update its content.
2009 I edited a book by Yoichi Ando on architectural acoustics that is grounded
on psychological and neurophysiological observations of listener percepts and
preferences (Auditory and Visual
Sensations, Springer, November, 2009).
Ando's approach is a rational theory of design that optimizes concert hall shapes based on acoustical models, psychoacoustics of auditory percepts, and measured listener preferences.
I believe that Ando is also unique in taking architectural acoustics inside the listener by measuring and modeling the neural processes involved in the listener's percepts and preferences.
(as if this were not enough in and of itself), Ando and his co-workers
have applied the same correlation-based approach to simple visual
percepts and preferences (temporally-modulated light, oscillating forms,
and spatial textures).
The book is available through Springer, Amazon, and the usual outlets in print and e-book formats (Google Books link). Here is a presentation of the book that I gave at Boston University. (PDF).
shorter, 40 page concise outline of Ando's theory will appear in a
forthcoming Springer volume commemorating the late Manfred Schroeder.
Workshop paper on "Designing for
Open-Ended Evolution" (PDF).
Scholarpedia article on "The Jeffress Model". (PDF) Article in progress, comments are welcome.
Presentation to session on “Flattening Federal research funding: The local angle”, Annual meeting of the Association of Health Care Journalists, Alexandria, VA, Friday, March 28, 2008, "The NIH Flat-funded: A view from the ground level. (PDF).
Publications: with links to viewable and downloadable documents
NSF-BITS Project Site
coding and related issues
Temporal coding clearinghouse: collating evidence from different modalities and systems.
The problem of neural coding:
Which aspects of neural response convey functionally-relevant
Patterns of spikes vs. patterns of channel-activations
Temporal coding of sensory information:
As if time really mattered: temporal strategies of sensory coding (1995)
(Download pdf format, 204k)
General theory and examples from different modalities
The many consequences of phase-locking
Extrinsic, stimulus-drive time structure vs. intrinsic, stimulus-evoked time structure
Temporal coding of pitch and timbre in the
Population-interval representations in the coding of pitch (pdf)
Population-interval distributions and autocorrelation (pdf)
Temporal discharge patterns in the auditory nerve. When a periodic sound is presented to the ear, it impresses its own temporal structure on the discharges of auditory nerve fibers. As a consequence of this stimulus-driven time structure, there exist correlations between timings of spikes and the stimulus waveform ("phase-locking"). In this case the stimulus is a single-formant vowel, with a fundamental frequency of 80 Hz and most spectral energy in harmonics near 640 Hz (formant frequency), presented 100 times at 60 dB SPL. The stimulus produces a strong "voice pitch" at its fundamental, and this periodicity can be seen in the discharge patterns of auditory nerve fibers across the auditory nerve array. When time durations between both successive and nonsuccessive spikes are tabulated in an interspike interval histograms, intervals related to the fundamental period (pitch period) and to spectral shape (tone quality, timbre) are seen. For harmonic stimuli, the most frequent intervals in the auditory nerve are those associated with the fundamental, such that the pitch that is heard invariably corresponds to the most frequent interspike interval. Exceptions to this rule involve stimuli that produce buzzy, rate-pitches an octave above the fundamental as well as some subtle pitch shifts that can occur with large changes in level.
The figure on the right shows two possible neural representations of the stimulus. The two plots on the left show the power spectrum of the vowel and the average firing rates of auditory nerve fibers as a function of their characteristic frequency. Average rate information from this number of fibers is not sufficient to identify the frequencies of individual harmonics in the stimulus that would be necessary to support a spectral pattern analysis of pitch. The plots on the right show the stimulus autocorrelation function and the population-interval distribution formed by summing all-order intervals from all fibers (i.e. the interval statistics of the whole auditory nerve). The population-interval distribution constructed from the responses of these fibers contains on the order of 100,000 intervals, and is sufficient to estimate the fundamental frequency (1/F0) with ~1% accuracy. This is in the ballpark of the ability of humans to detect changes in pitch on the order of fractions of a percent. A major advantage of interval codes over rate codes is that representations of stimulus periodicities remain highly invariant over a very wide dynamic range.
Neural coding and stimulus equivalence: an example of psychoneural
isomorphism. Neural responses to four stimuli evoking a pitch at 160 Hz
but differing in pitch salience. Left to right: Stimulus waveform,
power spectrum, short term autocorrelation function, and
population-interval distribution for each stimulus. Population-interval
distributions are constructed by summing together the all-order
interspike interval distributions of many auditory nerve fibers
(n=49-85) having a wide range of characteristic frequencies. These
interval distributions share a common feature: the most frequent
interspike intervals present correspond to the pitch period and its
multiples. While the top four stimuli give rise to strong definite
pitches, the bottom two evoke weak, more diffuse pitches. Pitch
salience qualitatively corresponds to the fraction of pitch-related
intervals in the whole interval distribution (quantified in terms of
peak-to-mean ratios in the distribution).
Coding of pitch in the auditory cortex
Temporal coding and speech
Towards an temporal theory of speech perception
Similarities and differences between autocorrelation and modulation detection operations
Voice onset time
Temporal cues associated with frequency shifts
Implications for cochlear implants
Implications for speech recognition
Interval-based front-ends for speech recognizers
Running summary autocorrelations as alternatives to spectrograms
Autocorrelation-based recognition strategies
P. (2004). A temporal model for pitch multiplicity and tonal
consonance. Proceedings, Int. Conf Music Perception &
(ICMPC), 4 pp., Evanston, IL, August 3-8, 2004.
P. Cariani. (2001). Temporal codes, timing
nets, and music perception. J. New Music Research.
Tramo, MJ, Cariani, PA, Delgutte,
B, Braida, LD. 2001 Neurobiological Foundations for the Theory of
Harmony in Western Tonal Music. Annals, New York Academy of Sciences,
vol 92, pp. 92-116 (PDF, 8.9 Mb).
Temporal coding and music
Pitch and timbre
Autocorrelation-based model of tonal context (e.g. Krumhansl note-key correlations)
Rhythm (pdf working paper on timing nets and rhythm)
P. Cariani. (2001a). Neural timing nets. Neural Networks, in press. (Uncorrected proofs, pdf)
P. Cariani. (2001b). Neural timing nets for auditory computation. In S. Greenberg & M. Slaney (Eds.), Computational Models of Auditory Function (pp. 235-249). Amsterdam: IOS Press.
P. Cariani. (2001). Temporal codes, timing nets, and music perception. J. New Music Research (in press).
Neural timing nets for utilizing
Extraction of similarities, buildup & separation of objects
computations in the time domain (ARO1998 poster)
View as HTML webpage
Download pdf file
Auditory object formation through temporal coherence (ARO2000 Poster, in pdf format)
Extensions of timing networks to frequency-by-frequency analysis
of high level integration of neural information
Signal multiplexing, emergence of new signal-primitives, broadcast models of coordination (pdf, 204k)
Regenerative processes (pdf, 68k)
Closing the loop: common time structure in perception and action
Relational alternatives to feature detection, perceptual atoms, and decision trees (thinking in progress)
an evolutionary robotics:
a taxonomy of adaptive systems (Short paper, pdf)
Purely computational devices
Robotic devices with fixed sensors, effectors, and coordinative faculties
Robotic devices with adaptive coordinative faculties
Robotic devices with adaptive sensors and/or effectors
• Gordon Pask's adaptive electrochemical device
Self-constructing, self-modifying evolutionary robotic devices
Epistemic autonomy: systems that determine their own categories vis-a-vis the environment
• Cariani P. On the design of devices with emergent semantic functions. Ph.D. Thesis, State University of New York at Binghamton, 1989; 234 pp. Download pdf file (7 Mb)
• Links to other theoretical biology sites (forthcoming: Pattee, Rosen, Kampis, Conrad, Emmeche, Moreno & others)
• Bibliography of theoretical biology
• Interview with Robert Rosen on the evolution of his ideas
(VHS-NTSC, 2 hrs, April, 1998, available upon request)
• Cariani, P. (1991) Emergence and artificial life. In: Artificial Life II, SFI Studies in the Sciences of Complexity, vol X, edited by C.G. Langton, C. Taylor, J.D. Farmer, & S. Rasmussen, Addison-Wesley, pp. 775-796. (Download pdf, 9 Mb)
on Cybernetics, Connectionism and Hayek's Sensory Order
Psychoneural isomorphism: neural codes and the
structure of perception (colloquium abstract)
alternative visions of the future: social institutions that enhance
The Mondragon industrial cooperatives: worker-owned, worker-controlled enterprises in a free-market framework
Gramin Banks: bottom-up economic development
Waiting for the Big One : 1) is the world financial system inherently stable?
2) long economic waves and dynamical systems, is Kondratieff really dead and gone?