Imagery , Creativity, Brains and Talent

1. Imagery, Creativity, Brains and Talent Włodek Duch Department of Informatics, Nicolaus Copernicus University, Torun, Poland. Google: W. Duch Hitachi Advanced Research Laboratory, July 2010

2. Toruń

3. Norbert Tomek Marek Krzysztof

4. Copernicus Nicolaus Copernicus: born in Torun in 1472

5. DI NCU Projects: CI Google W Duch => List of projects, talks, papers Computational intelligence (CI), main themes: • Foundations of computational intelligence: transformation based learning, k-separability, learning hard boole’an problems. • Meta-learning, or learning how to learn. • Understanding of data: prototype-based rules, visualization. • Novel learning: projection pursuit networks, QPC (Quality of Projected Clusters), search-based neural training, transfer learning or learning from others (ULM), aRPM, SFM ... • Similarity based framework for metalearning, heterogeneous systems, new transfer functions for neural networks. • Feature selection, extraction, creation.

6. DI NCU Projects:NCI Neurocognitive Informatics projects. • Computational creativity, insight, intuition, consciousness. • Neurocognitive approach to language, word games. • Medical information retrieval, analysis, visualization. • Global analysis of EEG, visualization of high-D trajectories. • Brain stem models and consciousness in artificial systems. • Autism, comprehensive theory. • Imagery agnosia, especially imagery amusia. • Infants: observation, guided development. • A test-bed for integration of different Humanized Interface Technologies (HIT), with Singapore C2I Center. • Free will, neural determinism and social consequences.

7. Visual imagery Large field, with several journals, ex: • Journal of Mental Imagery (1977), official journal of the International Imagery Association (not much neuroscience). • Imagination, Cognition and Personality (1980), mostly psychological. • Journal of Imagery Research in Sport and Physical Activity (2007). • Neuroimaging of Mental Imagery: A Special Issue of the European Journal of Cognitive Psychology (2004) • S. V. Thompson, Visual Imagery: a discussion. Educ. Psych. 10, 1990 , 141-167 • Individual differences in visual imagery, together with a lack of understanding that others may think in a radically different way in this respect, may have had a profound effect on theories of thought and knowledge, yet attempts to validate measures of this variable in terms of educationally significant correlates have been relatively unsuccessful. • Verbalizers and Imagers, division important in education.Better tests? More subtle divisions? Statistics?

8. Imagery and brains How and where are mental images formed? • Borst, G., Kosslyn, S. M, Visual mental imagery and visual perception: structural equivalence revealed by scanning processes. Memory & Cognition, 36, 849-862, 2008. • The present findings support the claim that image representations depict information in the same way that visual representations do. • Cui, X et al. (2007) Vividness of mental imagery: Individual variability can be measured objectively. Vision Research, 47, 474-478. • Reported Vividness of Visual Imagination (VVIQ) correlates well with the early visual cortex activity relative to the whole brain activity measured by fMRI (r=-0.73), and the performance on a novel psychophysical task. Findings emphasize the importance of examining individual subject variability. • Poor perceptual imagery: why? Weak top-down influences? Unable to draw from memory, describe details, faces, notice changes, etc.

9. What is needed to have qualia? Sensory cortex, for example V4 for color, MT for movement. Bottom-up and top-down activations create resonant states. What if top-down connections are weak or missing? C. Gilbert, M. Sigman, Brain States: Top-Down Influences in Sensory Processing. Neuron, Volume 54, Issue 5, Pages 677-696, 2007 Cortical & thalamic sensory lower-level processes are shaped by complex top-down influences, attention, task-related expectations and sensory inputs. Brain states are determined by the interactions between multiple cortical areas and the modulation of intrinsic circuits by feedback connections. Disruption of this interaction may lead to behavioral disorders. Dehaene et al, Conscious, preconscious, and subliminal processing. TCS 2006 Bottom-up strength & top-down attention combined lead to 4 brain states, with both stimulus and attention required for conscious reportability. Imagery? Electric shock activates auditory cortex through amygdala pathway, same with imagined scary episodes.

10. Visual top-down • Normal perception requires top-down influences to form expectations. • What if PC/FC feedback connections to visual/auditory areas are weak? • This does not qualify as agnosia, but is a kind of imagery agnosia, a syndrom that has not yet been clearly identified! How will the weak top-down connections in visual modality manifest? Attention problems? Only if signals are very weak (ex. in poor lighting conditions) object recognition may be impaired. Other symptoms: poor visual imagination, memory for visual features, inability to draw from memory, recall and describe faces and objects, notice changes, slow in making puzzles, difficulty to see 3D magic eye pictures, perhaps more introvert? More conceptual than perceptual thinking … recognition memory may work fine. At PC/FC level less interferences from sensory areas, so imagination, creativity, reasoning are fine, perhaps even better than average.

11. Auditory Perception Much less research has been done with auditory perception than visual. Peretz, I., Champod, S. & Hyde, K, Varieties of Musical Disorders: The Montreal Battery of Evaluation of Amusia. Annals of the New York Academy of Sciences, 999, 58-75, 2003. Model of music perception behind the MBAE test does not include imagery.

12. Music Perception Cognitive model of music processing is focused on pitch and rhythm processing: pitch in lateral Heschl’s gyrus, timbre in posterior superior-temporal lobes, rhythm in motor/mesiolimbic areas. Conscious hearing requires activation of the auditory cortex . Books that teach improvisation encourage imaging and hearing the effect of playing internally. Cognitive model of music processing: no imagery, no top-down processes. Peretz I, Coltheart M, Modularity of music processing, Nature Neuroscience, vol. 6(7), 688-691, 2003; model also used in: Stewart L. et al. Music and the brain: disorders of musical listening. Brain, 129, 2533-2553, 2006.

13. Music Imagery fMRI hemodynamic increase during an Auditory Imagery Task performed in silence, in the auditory cortex posterior superior temporal gyrus. Zatorre & Halpern, Mental Concerts: Musical Imagery and Auditory Cortex, Neuron 47, 9-12, 2004. Aural imagery or inner hearing is considered to be an important aspect of musical development. Musicians need to connect the sound they desire with a "feel" they know will produce that sound. The goal of music performance is the reproduction of the internal auditory image. (D.R. Allen musicology thesis, 2007) “An anticipatory image of feedback from an action participates in the selection and initiation or that action. [...] In the closed-loop formulation, the image may serve as a template for comparison with current feedback and need not be activated prior to performance.” A.G. Greenwald, Psych. Rev, 77, 73-99, 1970.

14. Music deficits Stewart et. al, Music and the brain: disorders of musical listening. Brain, 129, 2533-2553, 2006, long review. Pitch change directions, intervals, melodic patterns, contours, tonal structure, timbre, temporal structures (intervals, rhythm and meter), memory and emotional responses due to neurological problems are described. Congenital amusia: true perceptual agnosia, although hearing and cognition is normal perception of music is not, usually deficit in pitch processing. Mandell J, Schulze K, Schlaug G, Congenital amusia: An auditory-motor feedback disorder? Restorative Neurology and Neuroscience 25, 2007 “Thus, it is conceivable that individuals with congenital amusia, or the inability to sing in tune, may actually have an impairment of the auditory-motor feedback loop and/or auditory-motor mapping system.” Conceivable, but some may have simply poor top-down feedback. This seems to be a condition that has not been clearly identified, a new kind of imagery amusia, the inability to imagine sounds.

15. Amusia and spatial processing Anatomical locus of amusia, neuroimaging/lesion studies: auditory areas along the superior temporal gyrus in pitch discrimination and melodic contour processing. But amusics show deficits relative to musicians and nonmusicians, in tasks that involve spatial processing. Douglas, K.M. & Bilkey, D.K. Nature Neurosci. 10, 915-921 (2007) No evidence for morphological correlates of amusia in parietal regions. “The deficit may derive from changes in neural functioning that are invisible to the tools that have been applied to date.”

16. IQ and chronometry In experiments that distinguish whether high/low tone was first 4 groups of people differening by their IQ showed clear correlation between % of errors depending on time intervals that changed from 5-300 ms. J. Dreszer (UMK Torun), E. Szelag (Nencki Institute, Warsaw)

17. Parietal cortex A. Tosoni et al, Nature Neuroscience (Nov 2008 | doi:10.1038/nn.2221) Sensory-motor mechanisms in human parietal cortex underlie arbitrary visual decisions. In arbitrary association of visual stimuli with different actions, activity of effector-specific regions in human posterior parietal cortex did not respond to sensory stimuli per se, but to integrated sensory evidence toward the decision outcome, triggered by contextual stimulus-response associations. Hypothesis: normal perception requires top-down influences to form expectations. What if feedback connections to visual/auditory areas are weak? C. Gilbert, M. Sigman, Brain States: Top-Down Influences in Sensory Processing. Neuron 54, 677-696, 2007. “New findings on the diversity of top-down interactions show that cortical areas function as adaptive processors, being subject to attention, expectation, and perceptual task. Brain states are determined by the interactions between multiple cortical areas and the modulation of intrinsic circuits by feedback connections. ... Disruption of this interaction may lead to behavioral disorders.”

18. Imagery Agnosia New branch of neuropsychology: imagery agnosias. Classical agnosias~30 major types: alexia, akinetopsia, alexithimia, many visual types: prosopagnosia, simultanagnosia, semantic agnosia , form, color … Little access to perceptual imagery in visual, auditory, tactile or gustatory mode. Without internal feedback the only way to learn about plans formed by the brain is to act and observe results: trying to play an instrument in this condition is like blindsight, maneuvering blindly in the auditory space, without the ability to imagine results of next move (hitting piano key). • Learning to play music without imagery is difficult – how far can one go? Which key do I have to press if I have no idea how it will sound like? • Recognition memory is fine, but it is difficult to repeat or remember simple melodies (memory-motor map). • No problem to read & improvise music, higher cognition is fine. • Conscious mental rehearsal is not possible. • Immediate feedback may help?

19. The Listener James C. Christensen

20. Extended mind Philosophers talk about parts of environment (notebooks for external memory etc) tightly coupled to our motor and cognitive activity as “extended mind”. • Robert K. Logan, The Extended Mind: The Emergence of Language, the Human Mind and Culture. University of Toronto Press 2007 Inability to consciously interpret internal brain states leads to the need to express and recognize them through various bodily actions. • David Kirsh, Interactive Cognition Lab at UCSD, thinking by doing. • Understanding oneself = own brain states, allows for self-reflection and better self-regulation, but information flow in the brain is not perfect. • Spontaneous thoughts are the main source of knowing, but acting out, motor activity also help to recognize brain processes (ex. humming melodies). Imagery agnosia may be rather common (more common than classical agnosia). • Investigation of this condition may elucidate relations between conscious and unconscious processes in implementation of higher cognitive functions.

21. Practical implications Better understanding of these issues will have far reaching implications for education, assessment of talent, understanding role of conscious experiences. • Work on VVIQ-like questionnaire-based evaluation of auditory imagery. • Repeat ERP experiments using NIR-OT (Janata, Zatorre) – imagery of missing sounds, priming cadences, look at auditory cortex response. • Development of simple tests for imagery agnosia, correlations of such tests with NIR-OT, ERP studies. Ex: Correlation of sounds with buttons: memory for mapping sounds to buttons should correlated with the ability to imagine sounds; as memory for images should correlate with ability to draw from memory. • Collecting statistical data, ex. children in music classes at school, correlation of IA with grades in different subjects? • Gender differences? • Can one recover from imagery agnosia? Neurofeedback? Is it good goal?Influence of intensive musical training on auditory cortex activation. • Neuroimaging: top-down and bottom-up distinction?

22. Mental energy Can one train willpower, motivation, perseverance, curiosity and creativity using neurofeedback? Thinking and self-control requires mental energy derived from food. Higher levels of blood glucose reduce reliance on intuitive, heuristic-based decision making and help controlling attention, regulating emotions, coping with stress, resisting impulsivity, refraining from aggressive behavior. Alcohol reduces glucose levels impairing many forms of self-control. Self-control failure is most likely during times of the day when glucose is used least effectively. • Willpower and glucose • Gailliot MT & Baumeister RF (2007) The physiology of willpower: Linking blood glucose to self-control. Personality and Social Psychology Review, 11, 303-327. • Masicampo EJ & Baumeister RF (2008) Toward a physiology of dual-process reasoning and judgment: Lemonade, willpower, and effortful rule-based analysis. Psychological Science, 19, 255-260. • Sufficient energy for mental activity is a necessary condition.

23. EEG and creativity • John H. Gruzelier (Imperial College), SAN President • a-qneurofeedback produced “professionally significant performance improvements” in music and dance students. Neurofeedback and heart rate variability (HRV) biofeedback. benefited performance in different ways. • Musicality of violin music students was enhanced; novice singers from London music colleges after ten sessions over two months learned significantly within and between session the EEG self-regulation of q/a ratio. • The pre-post assessment involved creativity measures in improvisation, a divergent production task, and the adaptation innovation inventory. Support for associations with creativity followed improvement in creativity assessment measures of singing performance. Why? • Low frequency waves = easier synchronization between distant areas. • Background processes and parasite oscillations decrease (can one see it with NIR-OT or EEG?). How to increase cooperation between distant brain areas important for creativity?

24. Neurocognitive informatics My own attempts - see my webpage, Google: W. Duch Mind as a shadow of neurodynamics: geometrical model of mind processes, psychological spaces providing inner perspective as an approximation to neurodynamics. Intuition: learning from partial observations, solving problems without explicit reasoning (and combinatorial complexity) in an intuitive way. Neurocognitive linguistics: how to find neural pathways in the brain. Creativity in limited domains + word games, good fields for testing. Duch W, Intuition, Insight, Imagination and Creativity, IEEE Computational Intelligence Magazine 2(3), August 2007, pp. 40-52 Use inspirations from the brain, derive practical algorithms!

25. Intuition Intuition is a concept difficult to grasp, but commonly believed to play important role in business and other decision making; „knowing without being able to explain how we know”. Sinclair Ashkanasy (2005): intuition is a „non-sequentialinformation-processing mode, with cognitive & affective elements, resulting in direct knowing without any use of conscious reasoning”. 3 tests measuring intuition: Rational-Experiential Inventory (REI), Myers-Briggs Type Inventory (MBTI)and Accumulated Clues Task (ACT). Different intuition measures are not correlated, showing problems in constructing theoretical concept of intuition. Significant correlations were found between REI intuition scale and some measures of creativity. ANNs evaluate intuitively? Yes, although intuition is used also in reasoning. Intuition in chess has been studied in details (Newell, Simon 1975). Intuition may result from implicit learning of complex similarity-based evaluation that are difficult to express in symbolic (logical) way.

26. Intuitive thinking Learning from partial observations: Ohm’s law V=I×R; Kirhoff’sV=V1+V2. Geometric representation of qualitative facts: + increasing, 0 constant, - decreasing. True (I-,V-,R0), (I+,V+,R0),false (I+,V-,R0). 5 laws: 3 Ohm’s 2 Kirhoff’s laws. All laws A=B+C, A=B×C , A-1=B-1+C-1, have identical geometric interpretation! 13 true, 14 false facts; simple P-space, but complex neurodynamics. Question in qualitative physics (PDP book): if R2increases, R1and Vtare constant, what will happen with current and V1, V2?

27. Words in the brain Psycholinguistic experiments show that most likely categorical, phonological representations are used, not the acoustic input. Acoustic signal => phoneme => words => semantic concepts. Phonological processing precedes semantic by 90 ms (from N200 ERPs). F. Pulvermuller (2003) The Neuroscience of Language. On Brain Circuits of Words and Serial Order. Cambridge University Press. Action-perception networks inferred from ERP and fMRI Left hemisphere: precise representations of symbols, including phonological components; right hemisphere? Sees clusters of concepts.

28. Neuroimaging words Predicting Human Brain Activity Associated with the Meanings of Nouns," T. M. Mitchell et al, Science, 320, 1191, May 30, 2008 • Clear differences between fMRI brain activity when people read and think about different nouns. • Reading words and seeing the drawing invokes similar brain activations, presumably reflecting semantics of concepts. • Although individual variance is significant similar activations are found in brains of different people, a classifier may still be trained on pooled data. • Model trained on ~10 fMRI scans + very large corpus (1012) predicts brain activity for over 100 nouns for which fMRI has been done. Overlaps between activation of the brain for different words may serve as expansion coefficients for word-activation basis set. In future: I may know what you’ll think before you will know it yourself! Intentions may be known seconds before they become conscious!

29. Connectome Project Brain-based representations of concepts should be possible.

30. Nicole Speer et al. Reading Stories Activates Neural Representations of Visual and Motor Experiences. Psychological Science(2010, in print). Meaning: always slightly different, depending on the context, but still may be clusterized into relatively small number of distinct meanings.

31. Hidden concepts • Language, symbols in the brain: phonological labels associated with protypes of distributed activations of the brain. Helps to structure the flow of brain states in the thinking process. Do we have conscious access to all brain states that influence thinking? Right hemisphere activations just give us the feeling wrong something here. • Right hemisphere is as busy as left – concepts without verbal labels? • Evidence: insight phenomena, intuitive understanding of grammar, etc. Can we describe verbally natural categories? • Yes, if they are rather distinct: see 20 question game. • Is object description in terms of properties sufficient and necessary? • Not always. Example: different animals and dog breeds. • 20Q-game: weak question (seemingly unrelated to the answer) may lead to precise identification! RH may contribute to activation enabling associations

32. Dog breeds 329 breeds in 10 categories: Sheepdogs and Cattle Dogs; Pinscher and Schnauzer; Spitz and Primitive; Scenthounds; Pointing Dogs; Retrievers, Flushing Dogs and Water Dogs; Companion and Toy Dogs; Sighthounds Write down properties and try to use them in the 20-question game to recognize the breed … fails! Visually each category is quite different, all traditional categorizations are based on behavious and features that are not easy to observe. • Ontologies do not agree with visual similarity. • Brains discover it easily => not all brain states have linguistic labels.

33. Creativity & Triads 3 steps to solve problem: • Get information, prepare or prime your network (“search space”). • Spread this information around specialized circuits that enhance/modify it. • Filter the most relevant result. • Iteratively repeated search for solution constrained by knowledge that is already present in the network. • Blind-variation and selective-retention (Campbell 1960, Simonton 2010). • Creativity in word domain: assuming that the network has been trained on some language and has at least captured its statistical regularities: • Prime the network with description of your product. • Imagery creates large number of novel constituents. • Filter using phonological and semantic density. • But what insight do I have into the result? Self filters the most relevant ones. • Free will and action: self acts as a filter selecting alternative plans for actions.

34. Creativity with words The simplest testable model of creativity: • create interesting novel words that capture some features of products; • understand new words that cannot be found in the dictionary. Model inspired by the putative brain processes when new words are being invented starting from some keywords priming auditory cortex. Phonemes (allophones) are resonances, ordered activation of phonemes will activate both known words as well as their combinations; context + inhibition in the winner-takes-most leaves only a few candidate words. Creativity = network+imagination (fluctuations)+filtering (competition) Imagination: chains of phonemes activate both word and non-word representations, depending on the strength of the synaptic connections. Filtering: based on associations, emotions, phonological/semantic density. discoverity = {disc, disco, discover, verity} (discovery, creativity, verity)digventure ={dig, digital, venture, adventure} new! BrainGene server: http://www.braingene.yoyo.pl/ novel names, passwords …

35. Context  System Connectivity Categories Critic Idea Dynamic Selection Network (DSN) Concepts Type Features Each activated concept corresponds to the resonant activity of a multi-level network. Ali Minai architecture for creative associations, WCCI10 Descriptive Features

36. Problems requiring insights Given 31 dominos and a chessboard with 2 corners removed, can you cover all board with dominos? Analytical solution: try all combinations. Does not work … to many combinations to try. chess board domino n Logical, symbolic approach has little chance to create proper activations in the brain, linking new ideas: otherwise there will be too many associations, making thinking difficult. Insight <= right hemisphere, meta-level representations without phonological (symbolic) components ... counting? o m black white i d o phonological reps

37. Insights and brains Activity of the brain while solving problems that required insight and that could be solved in schematic, sequential way has been investigated. E.M. Bowden, M. Jung-Beeman, J. Fleck, J. Kounios, „New approaches to demystifying insight”.Trends in Cognitive Science2005. After solving a problem presented in a verbal way subjects indicated themselves whether they had an insight or not. An increased activity of the right hemisphere anterior superior temporal gyrus (RH-aSTG) was observed during initial solving efforts and insights. About 300 ms before insight a burst of gamma activity was observed, interpreted by the authors as „making connections across distantly related information during comprehension ... that allow them to see connections that previously eluded them”.

38. Insight interpreted What really happens? My interpretation: • LH-STG represents concepts, S=Start, F=final • understanding, solving = transition, step by step, from S to F • if no connection (transition) is found this leads to an impasse; • RH-STG ‘sees’ LH activity on meta-level, clustering concepts into abstract categories (cosets, or constrained sets); • connection between S to F is found in RH, leading to a feeling of vague understanding; • gamma burst increases the activity of LH representations for S, F and intermediate configurations; feeling of imminent solution arises; • stepwise transition between S and F is found; • finding solution is rewarded by emotions during Aha! experience; they are necessary to increase plasticity and create permanent links.

39. Solving problems with insight Neuromodulation (emotions) Goal Steps Right temporal lobe Start: problem statement Left temporal lobe

40. Mental models Kenneth Craik, 1943 book “The Nature of Explanation”, G-H Luquet attributed mental models to children in 1927. P. Johnson-Laird, 1983 book and papers. Imagination: mental rotation, time ~ angle, about 60o/sec. Internal models of relations between objects, hypothesized to play a major role in cognition and decision-making. AI: direct representations are very useful, direct in some aspects only! Reasoning: imaging relations, “seeing” mental picture, semantic? Systematic fallacies: a sort of cognitive illusions. • If the test is to continue then the turbine must be rotating fast enough to generate emergency electricity. • The turbine is not rotating fast enough to generate this electricity. • What, if anything, follows? Chernobyl disaster … If A=>B; then ~B => ~A, but only about 2/3 students answer correctly.

41. Mental models summary The mental model theory is an alternative to the view that deduction depends on formal rules of inference. • MM represent explicitly what is true, but not what is false; this may lead naive reasoner into systematic error. • Large number of complex models => poor performance. • Tendency to focus on a few possible models => erroneous conclusions and irrational decisions. Cognitive illusions are just like visual illusions. M. Piattelli-Palmarini, Inevitable Illusions: How Mistakes of Reason Rule Our Minds (1996) R. Pohl, Cognitive Illusions: A Handbook on Fallacies and Biases in Thinking, Judgement and Memory (2005) Amazing, but mental models theory ignores everything we know about learning in any form! How and why do we reason the way we do? I’m innocent! My brain made me do it!

42. P.McLeod, T. Shallice, D.C. Plaut, Attractor dynamics in word recognition: converging evidence from errors by normal subjects, dyslexic patients and a connectionist model. Cognition 74 (2000) 91-113. New area in psycholinguistics: investigation of dynamical cognition, influence of masking on semantic and phonological errors. Trajectories for psycholinguistics

43. Learning: mapping one of the 3 layers to the other two. Fluctuations around final configuration = attractors representing concepts. How to see properties of their basins, their relations? Model of reading & dyslexia Emergent neural simulator: Aisa, B., Mingus, B., and O'Reilly, R. The emergent neural modeling system. Neural Networks, 21, 1045-1212, 2008. 3-layer model of reading: orthography, phonology, semantics, or distribution of activity over 140 microfeatures of concepts. Hidden layers in between.

45. P-spaces Psychological spaces: how to visualize inner life? K. Lewin, The conceptual representation and the measurement of psychological forces (1938), cognitive dynamic movement in phenomenological space. George Kelly (1955): personal construct psychology (PCP), geometry of psychological spaces as alternative to logic. A complete theory of cognition, action, learning and intention. PCP network, society, journal, software … quite active group. Many things in philosophy, dynamics, neuroscience and psychology, searching for new ways of understanding cognition, are relevant here.

46. P-space definition P-space: region in which we may place and classify elements of our experience, constructed and evolving, „a space without distance”, divided by dichotomies. P-spacesshould have (Shepard 1957-2001): • minimal dimensionality; • distances that monotonically decrease with increasing similarity. This may be achieved using multi-dimensional non-metric scaling (MDS), reproducing similarity relations in low-dimensional spaces. Many Object Recognition and Perceptual Categorization models assume that objects are represented in a multidimensional psychological space; similarity between objects ~ 1/distance in this space. Can one describe the state of mind in similar way?

47. Attractors Attention results from: • inhibitory competition, • bidirectional interactive processing, • multiple constraint satisfaction. Basins of attractors: input activations {LGN(X)}=> object recognition • Normal case: relatively large, easy associations, moving from one basin of attraction to another, exploring the activation space. • Without accommodation (voltage-dependent K+ channels): deep, narrow basins, hard to move out of the basin, associations are weak. Accommodation: basins of attractors shrink and vanish because neurons desynchronize due to the fatigue; this allows other neurons to synchronize, leading to quite unrelated concepts (thoughts).

48. Recurrence plots Same trajectories displayed with recurrence plots, showing roughly 5 larger basins of attractors and some transient points. Starting from the word “flag”, with small synaptic noise (var=0.02), the network starts from reaching an attractor and moves to another one (frequently quite distant), creating a “chain of thoughts”.

49. Normal-ADHD All plots for the flag word, different values of b_inc_dt parameter in the accommodation mechanism. b_inc_dt = 0.01 & b_inc_dt = 0.02 b_inc_dt = time constant for increases in intracellular calcium which builds up slowly as a function of activation. http://kdobosz.wikidot.com/dyslexia-accommodation-parameters

50. Normal-Autism All plots for the flag word, different values of b_inc_dt parameter in the accommodation mechanism. b_inc_dt = 0.01 & b_inc_dt = 0.005 b_inc_dt = time constant for increases in intracellular calcium which builds up slowly as a function of activation. http://kdobosz.wikidot.com/dyslexia-accommodation-parameters