David Brang Anna Krasno Lee Edwards Amanda Gorlick Cogs 175 6/2/06

Outline 1. Lee - Synesthesia Primer 2. David 3. Anna 4. Amanda What it is, relation to consciousness 2. David Video, demographics, evidence, theories 3. Anna Acquired synesthesia, developmental vs. acquired 4. Amanda Conscious understanding - closing remarks

What is Synesthesia? Perceptual phenomenon Grapheme Color Inducer and concurrent Developmental synesthetes No Comorbidity with mental illness Perceptual phenomenon characterized by the mixing of senosory modalities, such that stimulation of one sense will elicit sensation of a second sense. The most common cases of synesthesia occur in Developmental synesthetes and the most common type of synesthesia is grapheme color synesthesia. Developmental synesthetes experience these sensations consistently from childhood, they occur automatically, etc. Grapheme color synesthesia is the perception of colors upon viewing numbers Not pathology Same inducer can elicit a different concurrent in between synesthetes

Correlates to Consciousness Can be thought of as an altered state The world is perceived differently, relative to non-synesthetes Cross modal integration Relevance Flower - smell, see, feel, but we combine into one sense Relevance - Synesthesia prime example of cross-modal integration, so can be reduced to the modal integration of non-syns

Now we have a short video from an interview with a synesthete.

Demographics The majority of synesthetes report the experience since childhood Occurs in at least 1/2000 individuals More common in children than adults More common in women Has a genetic basis to it Theorized 50 separate forms of synesthesia This individual is an developmental, color grapheme synesthete, which Lee described as being the most common form of syn Devlopmental Syns report their experiences from childhood, and accordingly they become so imbeded into the conscious experience, most are surprised to find not everyone is like them. Theorized to be as common as 1/200 according to Rama and Hubbard 36% claim they have biological relatives 1/2 say don’t, so environmental factors If have one, more likely to have a second or more Evidence exists for at least 35 separate forms of syn, but rama has theorized there may be upwards of 50 types. Another well documented form of synesthesia occurs in individuals who percieve time as visual space, many in an oval shape

Evidence as a Phenomenon Test/retest reliability Similar reports across cultures and time PET studies fMRI studies Synesthetic Stroop Test Test/retest: tests of genuiness synesthetic matched colored word pairings taught to non syns, tested associations 10 weeks later: 38% of nons remembered pairings, compaired to a year later 92% of syns remembered pairings Baron-Cohen 1993 Similar reports: Syn not limited to the western world, described through lit over centuries PET - Aud grapheme, diff bloodflow in syn women that norm women fMRI - listening to words (color hearing) showed V8/V4 activation compared to controls controls overtrained to imagine colors for words, had no effect evidence against learned association Confounds: often use very few subjects, use same subjects in multiple experiements, so much individual variability across synesthetes

Theories Learned association Awareness Neural Connectivity Neonatal Cross-wiring Disinhibited feedback Gamma-Binding Except for “learned association” these other theories are developmental

Acquired Brain damage Retinitis pigmentosa Sensory deafferentation Drugs Meditation Occurs through LSD and mescaline Retinitis pigmentosa= become blind over time, genetic, get tunnel vision, don’t become legally blind until 40s, 50s. Abnormality of photoreceptors, vision deteriorates over time. Sensory deafferentation= processing of somatosensory feedback is impaired but motor abilities intact

Developmental vs. Acquired Devlopmental Acquired Involuntary Transient experience Synthetic Perception and Conception Perception only Consistent across lifetime Not verifiable over time Part of normal consciousness Not brought into self-awareness Often unreported Novelty of event communicated Can’t be ignored Consistency means daily since childhood Synesthesia is neither strategy nor attitude Synthetic perception=Actual sensory stimuli lead to an induced concurrentneed something tangible (ex. See a number on a page and see it in a certain color) Conception=Think about concepts and have concurrence think about the number and also see that color Not brought into self-awareness= they report it, not part of their self-concept, of their normal consciousness

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Towards a Conscious Understanding Booba and kiki “Conceptual rightness” Synesthesia is present and suppressed in normal individuals, but has the potential to rise to consciousness Only consistently part of consciousness in developmental synesthetes Ramas stuff - evolution of culture conceptual Some evidence shows that the associations do have a basis in the childhood specific to the individual Paraphrase: Cytowik theorizes, Different cause this is a subconscious experience for normal individuals Developmentals pass this line that crosses into awareness

Conclusion Altered state is unique to the baseline state of each individual Umbrella including autism and other developmental disorders Personal reality NOT US AND THEM, must be defined from within Everyone thinks they’re normal and that’s there reference point Developmentals think they’re normal until they find out others don’t mix their sense This theory of consciousness can be extended to developmental pathologies. Since syn isn’t a disorder, best way to classify. Developmental syns know this phenomenon as their personal reality Similar scenario w/autistics, a developmental population that has a unique state of consciousness since birth that is “different” than ours so we tend to say that it is an altered state. Can’t acquire it. We are unable to understand their state of consciousness. The way they see the world is normal to them. Can’t relate our own consciousness to a completely separate group of people. Synesthesia will help us learn about other disorders that are unique to a population. Helping us know that we can’t define altered states. Synesthesia is highly variable. There is a wide spectrum both with autism and synesthesia.

There is large variability within the normal state among individuals and therefore there is a large variability of altered states. Even “altered” states vary within each individual. If not really a normal consciousness, how can we say that there is an altered state?

References Baron-Cohen, Simon. (1996) “Is there a normal phase of synesthesia in development? Psyche, 2(27) Calkins, M.W. (1893). “A statistical study of pseudo-chromesthesia and of mental-forms.” American Journal of Psychology, 5, 439-66. Cytowic, R.E. (1989). “Synesthesia: A Union of the Senses.” Springer Verlag. Galton, F. (1880). “Visualized numerals.” Nature, 21: 252-256. Grossenbacher, P.G. & Lovelace, C.T. (2001). “Mechanisms of synesthesia: cognitive and physiological constraints.” TRENDS in Cognitive Sciences, 5: 36-41. Hubbard, Edward M. and V.S. Ramachandran. (2005) “Neurocognitive Mechanisms of Synesthesia.” Neuron, 48:509-520. Lynn C. Robertson & Noam Sagiv (Eds). Synesthesia: Perspectives from Cognitive Neuroscience. New York: Oxford University Press, 2005. Maurer, D. et al., (1999). “Cross-modal transfer of shape is difficult to demonstrate in one-month-olds.” Child Development, 70 (5), 1047-57.

References Nunn, J.A. et al., (2002). “Functional magnetic resonance imaging of synesthesia: activation of V4/V8 by spoken words.” Nature Neuroscience, 5: 371-375. Paulesu, E. et al. (1995). “The Physiology of Coloured Hearing: A PET activation study of colour-word synaesthesia.” Brain, 118, 661-676. Ramachandran, V.S. and Hubbard, E.M. (2003). “Hearing colors, tasting shapes.” Scientific American. May 2003, 53-59. Ramachandran, V.S. & Hubbard, E.M. (2000). “Psychophysical investigations into the neural basis of synaesthesis.” The Royal Society, 268: 979-983. Rich, A.N, Bradshaw, J.L., J.B. Mattingley. (2004). “A Systematic, largescale study of synesthesia: Implications for the role of early experience in lexical-colour associations.” Cognition. 20(11): 1-32. Snyder, S.H. (1986). Drugs and the Brain. New York: Scientific American Library. Van Leeuwen, T. (2004) “The neural basis of synesthesia.” <http://bar.psych.ubc.ca/PDF/VanLeeuwen04_synpaper.pdf> May 28, 2006. Walsh, R. (2005). “Can synesthesia be cultivated?: Indications from surveys of meditators.” Journal of Consciousness Studies, 12, 5-17.