Scientific Understanding of Consciousness
Consciousness as an Emergent Property of Thalamocortical Activity

Language

For humans, language allows the efficient handling of high-level concepts. (Arbib - Handbook of Brain Theory and Neural Networks; Taylor; Self-Organization in Time Domain, 843)

A language system of the type found in humans is not essential for consciousness. (Crick; Astonishing Hypothesis, 23)

Language is probably not required for consciousness. (Zeman; Consciousness, 285)

Research Study — Speech Sensory–Motor Transformations occur Bilaterally

Research Study — Phonetic Feature Encoding in Cortex

Importance of processing on the (sub-)millisecond scale in the brainstem and the 1000+ millisecond scale for phrases, the two windows play a privileged role in the analysis and perceptual interpretation of audio signals. These two time windows have special consequences for speech perception. (Moore, et.al., Perception of Speech, 259)

Written words enter occipital pole in the form of visual patterns, and are then sent to the angular gyrus to make contact with the visual images of words, then propagated to Wernicke's area, the seat of auditory images for words, then on the Broca's area, where articulation patterns are retrieved, and finally to the motor cortex, which controls muscles. (Dehaene; Reading in the Brain, 64)

Phonemic or Orthographical Patterns Communicates Information

Ability to represent the phonemic or orthographical pattern that corresponds to a word is the means of communication; the goal is to communicate information, and the semantic representation of the concepts that a word stands for is the heart of language. (Fischler; Attention and Language, 388)

The general architecture of the network of neural pathways of the brain are genetically determined, but the microcircuitry that instantiates linguistic knowledge depends upon lifelong experience. (Philip Lieberman; Human Language, 68)

Spontaneous speech -- to speak a sentence requires that lexical, syntactical, sematic, phonetic, and prosodic competencies are all operative. (Arbib - Handbook of Brain Theory and Neural Networks; Poppel; Time Perception, 987)

Although the neural bases of language include the neocortex, some of the key functional language systems are subcortical basal ganglia -- our reptilian brain. (Philip Lieberman; Human Language, 1)

Human language is regulated by a distributed network that includes subcortical structures, the traditional cortical language areas (Broca's and Wernicke's areas) and regions of the neocortex often associated with "nonlinguistic" aspects of cognition. (Philip Lieberman; Human Language, 2)

Link to — Topics for Speech Perception

Research Study — Speech Organization in Cortex — Production of fluent speech requires the precise, coordinated movement of multiple articulators (for example, the lips, jaw, tongue and larynx) over rapid time scales. We found speech-articulator representations that are arranged somatotopically on ventral pre- and post-central gyri, which were coordinated temporally as sequences during syllable production.

Research Study — Language—Associated Gene SRPX2 Regulates Synapse Formation

Language Improves and Refines Thought

Language enables a more explicit and precise model of reality. Written language permits a more precise and enduring statement than oral language.

Ability to use language not just to communicate but to plan and direct future action is at the core of humanity. (Ratey; User's Guide to Brain, 253)

The language areas offer one of many routes to action, but a route particularly suited in planning actions, because of the syntactic manipulation of semantic entities, which may make the long-term planning possible. (Rolls; Emotion Explained, 401)

Language improves and refines our thoughts, allowing us to remove ourselves from the present, to symbolically hold objects in our minds and manipulate them into different potential sequences before taking action. (Ratey; User's Guide to Brain, 253)

It is the set of rules that we use to link the meaningless phoneme sounds -- our grammar and syntax -- that allows us to expressed and understand new ideas. (Ratey; User's Guide to Brain, 257)

44 distinct basic sounds (phonemes) that can be arranged into an infinite number of combinations. (Ratey; User's Guide to Brain, 253)

By the time we graduate from high school we know 45,000 to 60,000 words, and all are combined and recombined into phrases, sentences, and paragraphs. (Ratey; User's Guide to Brain, 257)

One reason human cognition is so powerful is because we have language in our brains, which exponentially increases the ability to categorize information. (LeDoux; Emotional Brain, 177)

Language exists in many species far older than Homo sapiens. Prosody is an outward gesturing of an internal state; smiling, laughter, frowning, lifting of one's eyebrows. (Llinás; I of the Vortex, 229)

Gestures and Social and Emotional Content

Speech involves not only the communication of vocabulary and grammatical content but also social and emotional content. (Miller; Human Frontal Lobes, 74)

Rhythmic, melodic intonation in speech that contributes social and emotional elements of meaning to language is term "prosody". (Miller; Human Frontal Lobes, 74)

Language is a system of abstract symbols and the grammar (rules) in which the symbols are manipulated. Language does not have to be spoken or written. It can be made with gestures, such as American Sign Language. Syntax is the pattern of formation of sentences or phrases that govern the way words in a sentence come together. Human language can string phrases together indefinitely to produce an unlimited number of sentences that are all different and have never been said before. (Gazzaniga; Human, 55)

Noam Chomsky, the distinguished linguist at MIT. (Gazzaniga; Human, 56)

Language Facilitates and Enriches Perceptual Categorization

Language facilitates the perceptual categorization of detailed thoughts and the communication of perceptions and memories.

Describing and understanding the functioning of computers requires the specialized nouns, verbs, adjectives, and adverbs that have evolved in the language.

The language related to molecular biology has evolved with specialized nouns, verbs, adjectives, and adverbs following the discovery of the structure of DNA by Watson and Crick.

Language is Lateralized in the Cortex

Even simple language tasks, although highly lateralized, activate a network of widely distributed left hemisphere cortical areas. (Miller; Human Frontal Lobes, 72)

Language disabilities such as stuttering are more common in the minority of people whose language areas are more equally split between hemispheres, perhaps indicating difficulties in coordination. (Ratey; User's Guide to Brain, 275)

Stuttering may be due to competition for dominance between left and right hemispheres. Neither side can decide which is in control, so that both try to produce words. (Carter; Mapping the Mind, 155)

Asymmetries of prosody and emotion. (Miller; Human Frontal Lobes, 74)

Language involves a simultaneous generation of several components -- a discourse plan that creates the overall shape of the language units to be spoken; a sentence plan that formulates the individual sentences and pronounces them sequentially; and a search through the verbal lexicon for the appropriate words to place in order within the sentence. (Andreasen, Creating Brain, 64)

Cerebellum is also involved in language and other cognitive functions. (Kandel; Principles of Neural Science, 322)

Listening to or recalling music lyrics involves language centers, including Broca's and Wernicke's areas, as well as other language centers in the temporal and frontal lobes. (Levitin; Your Brain on Music, 84)

Conjoining of nonverbal and verbal activated representations pertaining to concrete entities depends on a mediator mechanism in left anterior temporal cortices. The mechanism promotes the reconstruction of a word form given the concept, or, conversely, the reconstruction of the concept of an object given the word form. (Domasio; Convergence Zone, 66)

Language is fundamental to the development of sophisticated memories. (Ratey; User's Guide to Brain, 207)

Recognition vocabulary of educated English speakers contains about 100,000 words. (Baars, Essential Sources, 576)

Oral language

Spoken language involves the permutations of ~40 phonems by the human vocal track.

Spoken language involves Fixed Action Patterns (FAPs) in the Broca’s area, basal ganglia, cerebellum, and spinal cord.

Listening to spoken language involves FAPs in the auditory cortex, Wernicke area, parietal cortex, and frontal cortex.

While our brains are actively producing spoken language, we are often watching the face and body language of people listening to us, sometimes deciding to make changes in the in the discourse plan as we see them wince or laugh or smile. (Andreasen, Creating Brain, 64)

Production and Perception of Speech

The production and perception of human speech are intimately related. (Philip Lieberman; Human Language, 60)

Speech perception appears to involve knowledge of the articulatory maneuvers that can generate the sounds of speech, as well as the constraints imposed by human speech-producing anatomy and physiology. (Philip Lieberman; Human Language, 60)

The sound pattern of a word is the primary key to accessing the semantic and syntactic information that constitutes the meaning of a word. (Philip Lieberman; Human Language, 62)

The phonetic quality of the segmental sounds of speech is largely determined by their formant frequency patterns. (Philip Lieberman; Human Language, 42)

The motor command sequences that underlie the production of human speech are arguably the most complex that ordinary people attain. (Philip Lieberman; Human Language, 44)

The melody or prosody of speech has a central linguistic function -- segmenting the flow of speech into sentence-like units and highlighting words or phrases by means of "prominence" or "stress." (Philip Lieberman; Human Language, 58)

Research Study — Sensory-Motor Cortex Speech Map

Semantic Memory in Language

The domain of semantic memory consists of stored information about the features and attributes that define concepts and processes that allow us to efficiently retrieve, act upon and produce this information in the service of thought and language. (Semantic Working Memory System)

Left Prefrontal Cortex (LPC) plays a crucial role in retrieving lexical and semantic information. (Semantic Working Memory System)

Verbal Working Memory

Verbal working memory can be regarded as the neural computational space in which the meaning of a sentence is derived, taking account of syntactic, semantic, contextual, and pragmatic information. (Philip Lieberman; Human Language, 62)

The neural substrate that supports verbal working memory is a distributed system involving Wernicke's area, Broca's area, other cortical areas, and subcortical structures. (Philip Lieberman; Human Language, 77)

The brain's dictionary appears to be instantiated by means of a distributed network in which neuroanatomical structures that play a part in the immediate perception of objects and animals as we view them, or the gestures associated with tools as we use them, are activated. (Philip Lieberman; Human Language, 81)

Written language

Writing was born only 5400 years ago in the Fertile Crescent, and the alphabet itself is only 3800 years old. (Dehaene; Reading in the Brain, 4)

Reading a language involves FAPs for visual symbols in the visual cortex, parietal cortex, and temporal cortex.

Manual writing involves FAPs in the premotor and motor cortex basal ganglia, cerebellum, and spinal cord.

Written words enter occipital pole in the form of visual patterns, and are then sent to the angular gyrus to make contact with the visual images of words, then propagated to Wernicke's area, the seat of auditory images for words, then on the Broca's area, where articulation patterns are retrieved, and finally to the motor cortex, which controls muscles. (Dehaene; Reading in the Brain, 64)

The brain's “letterbox area” plays a crucial role in the fast identification of the letter string and its transmission to the higher areas that compute pronunciation and meaning. (Dehaene; Reading in the Brain, 62)

All the brain's regions operate simultaneously and in tandem, and their messages constantly crisscross each other. All the connections are bidirectional. (Dehaene; Reading in the Brain, 64)

Developmental neuroimaging studies in normal and dyslexic children show that, with reading acquisition, a specific brain site in left occipito-temporal cortex, which has been termed “visual word form area” (VWFA), starts to respond to orthographic stimuli in the learned script. (Cortical Networks for Vision and Language)

Reading

Reading uses a primate brain naturally selected for life in African savanna. (Dehaene; Reading in the Brain, 4)

Nothing in our evolution could have prepared us to absorb language through vision. (Dehaene; Reading in the Brain, 4)

Brain imaging demonstrates that the adult brain contains fixed circuitry exquisitely attuned to reading. (Dehaene; Reading in the Brain, 4)

Orthographic memories of word spellings are probably stored in the form of hierarchical trees of letters, graphemes, syllables, and morphemes. (Dehaene; Reading in the Brain, 41)

We also maintain a separate "phonological lexicon," a mental dictionary of the pronunciation of words. (Dehaene; Reading in the Brain, 41)

We also have a grammatical store that specifies words as a noun, that its plural is regular, etc. (Dehaene; Reading in the Brain, 41)

Each word is associated with dozens of semantic features that specify its meaning. (Dehaene; Reading in the Brain, 41)

Any reader easily retrieves a single meaning of at least 50,000 candidate words, in the space of a few tenths of a second, based on nothing more than a few strokes of light on the retina. (Dehaene; Reading in the Brain, 42)

Studies of human reading suggests that the reader's brain behaves much like a mental Senate. The recognition of a word requires multiple cerebral systems to agree on an ambiguous interpretation of the visual input. The time that it takes to read a word depends primarily on the conflicts and conditions that it sets into motion in the cortical architecture. (Dehaene; Reading in the Brain, 49)

Broca and Wernicke areas

Asymmetry of the cerebral hemispheres (Damasio; Descartes' Error, 66)

Language centers of the brain - (diagram) (Llinás; I of the Vortex, 152)

Language comprehension, Wernicke area. Speech syntax, Broca area. (LeDoux; Emotional Brain, 77)

For speech, each hemisphere is concerned with different aspects. Wernicke's area in the left hemisphere recognizes distinctive parts of speech, and an area in the right auditory cortex recognize prosody, the metric structure of speech. (Gazzaniga; Human, 28)

A component of Wernicke's area is larger in the left hemisphere than the right. Microscopic architecture of Wernicke's area is different from the corresponding part of the right hemisphere -- many columns are wider, and the spaces between them are greater, and this lateralized change in architecture is unique to humans. (Gazzaniga; Human, 28)

Split-brain research has demonstrated that the left hemisphere has marked limitations in perceptual functions and the right hemisphere has prominent limitations in cognitive functions. (Gazzaniga; Human, 31)

Imaging studies support the classic view of two left hemisphere regions being particularly important in the representation, maintenance, and production of phonological codes (FAPs) for language: the posterior portion of the left superior temporal gyrus, or Wernicke's area, and the dorsolateral portion of the left inferior frontal gyrus, or Broca's area. (Parasuraman, Attentive Brain; Fischler; Attention and Language, 387)

Wernicke's area is associated with the ideas aspect of speech. The aphasia is characterized by a failure to understand speech -- either written or spoken. (Eccles; Evolution of Brain, 81)

Broca area aphasia -- inability to speak fluently, although can understand spoken language. (Eccles; Evolution of Brain, 81)

In about 5% of cases, the lateralization of speech is reversed, Wernicke and Broca areas being on the right side. (Eccles; Evolution of Brain, 81)

Language in humans is mediated by the Broca and Wernicke areas, usually on the left side of the brain. The Broca area mediates spoken language; Wernicke’s area mediates the understanding of words and grammar. People with stroke damage to these language areas continue to experience consciousness.

Broca's area was active in tasks requiring discrimination of consonant sequences but not of vowels. 388)

Lesions encompassing more than areas 44 and 45 are necessary to produce the full syndrome of nonfluent aphasia. (Miller; Human Frontal Lobes, 71)

Even simple language tasks, although highly lateralized, activate a network of widely distributed left hemisphere cortical areas. (Miller; Human Frontal Lobes, 72)

Asymmetries of prosody and emotion. (Miller; Human Frontal Lobes, 74)

Research study — Sequential Processing within Broca’s Area — probes withinBroca’s area revealed distinct neuronal activity for lexical, grammatical, and phonological processing.

Link to Diagram— Friendly Conversation — hypothetical sketch diagram of cognitive and emotional functional activity in friendly conversation.

Research study — Cortical Networks for Vision and Language — functional magnetic resonance imaging, showed that even when literacy was acquired in adulthood, both childhood and adult education can profoundly refine cortical organization.

Basal ganglia circuitry in learning language vocalizations FAPs

The following research article relates to how the basal ganglia and associated circuits might be related to auditory and neuronal assemblies and thereby program FAPs for language vocalization. Because experimental neuronal studies on humans is usually not ethical, studies of homologous structures in animals can provide much insight.

Research study — Vocal Mirroring in Neurons — neurons respond in a temporally precise fashion to auditory presentation of certain note sequences in a songbird's repertoire and to similar note sequences in other birds' songs.

Language as a FAP

Vocalization of language uses fixed action patterns (FAPs) to produce the muscular movements of throat and breath that produce the vocalization. FAPs are also employed for the muscular finger movements that produce written language.

Language itself is a FAP. Broca's area is responsible for the generation of motor aspects of language. (Llinás; I of the Vortex, 151)

Studies have linked language production with complex motor skills, indicating that the two functions share neural networks. (Ratey; User's Guide to Brain, 272)

Brain uses its motor components to move our lips and tongue and palate so that the speech is well articulated, as our auditory system listens to what is being said and prepares the other components to make modifications. (Andreasen, Creating Brain, 64)

Learning a new language can be considered as the learning of FAPs to speak the words and idiom of the language. Neural networks with their synaptic connections must be ingrained and structured to quickly categorize audible sounds and to provide muscles with a hierarchy of FAPs to vocalize thoughts.

Semantic areas Widespread, Distributed Network

Nodes in the language network are widely distributed throughout the brain (diagram) (Andreasen, Creating Brain, 65)

Neural systems that represent the meaning of words have proved particularly challenging to isolate anatomically, which has led some researchers to conclude that semantic knowledge is by its nature diffusely represented, probably by a sort of distributed processing system. (Fischler; Attention and Language, 389)

Cell assemblies representing knowledge may be part of a distributed network. (Fischler; Attention and Language, 389)

This widespread functionality for semantics contrasts to the more specific functionality of the Broca area for vocal articulation and the Wernicke area for the construction and disassembly of sentences in terms of grammar and words.

Word meaning is often associated with sensory images, which are presumably more posterior. (Baars, Essential Sources, 323)

Humor is what happens when an assumption is epistemically committed to in a mental space and then discovered to have been a mistake. (Hurley, Dennett, Adams; Inside Jokes, 121)

Humans Innately Equipped with Natural Language Areas

Human species seems to be endowed with natural language. (LeDoux; Emotional Brain, 106)

Natural language only exists in the human brain. (LeDoux; Emotional Brain, 301)

Noam Chomsky; natural language is unique to humans; a universal grammar encoded in the human genome; certain psychological capacities are innate. (LeDoux; Synaptic Self, 83)

Noam Chomsky in 1980s claimed that a genetically determined capacity of language specifies a class of humanly accessible grammar. (Changeux; Neuronal Man, 180)

Phonemes Characterizing a Native Language learned in Childhood Years

Acquisition of phonemes that characterize a certain language; learned within a particular period of time; learn a particular language, but only at the expense of the ability to learn other languages. (Llinás; I of the Vortex, 194)

Brain images of language words

PET images, seeing words, hearing words, speaking words, generating words - (illustrations) (Calvin; Neil's Brain, 52)

Brain Self-Organizing and Language

Brain is a self-organizing system that can create novel linkages on a millisecond timescale. (Andreasen; Creating Brain, 64) [Gestalts]

When you hear a sentence, you have to make a mental model for what that string of sounds represents. A full understanding of an utterance may well involve many right-brain functions. (Calvin; Neil's Brain, 73)

While the left brain may be more involved with the building blocks of language, the right brain is quite helpful in interpreting it all. (Calvin; Neil's Brain, 74)

Link to — Consciousness Subject Outline