The four approaches to language & the brain
Part II's arc: a localizationist baseline and three reactions to it. Read across the row to compare them on each dimension.
The arc in one line
Connectionist localizationist centres → Hierarchical graded levels → Global one general capacity → Process localized shared sub-components. The last three are "holist" — though Luria's process model is a partial return to localization.
| Connectionist (Ch.4) | Hierarchical (Ch.7) | Global / Holist (Ch.8) | Process (Ch.9) | |
|---|---|---|---|---|
| Core idea | Whole language faculties sit in cortical centres joined by connections. | Language & brain are stacked levels; higher levels superimpose on, inhibit & modify lower ones. | One disturbed general capacity underlies all aphasia. | Every function is a process built from many small, localized, shared sub-components. |
| Key figures | Broca, Wernicke, Lichtheim (Geschwind) | Hughlings Jackson, Jakobson, Brown | Pierre Marie, Goldstein | A. R. Luria |
| Where language "lives" | Discrete centres (auditory & motor word-images, concept field) + white-matter tracts. | Distributed across evolutionary/developmental levels of the nervous system. | Not localized as language — a general factor (Marie's "intelligence"; Goldstein's "abstract attitude"). | Localized components, each shared by many functions. |
| How symptoms arise | Lesion a centre or a connection → a specific, predictable syndrome. | Negative (loss of a higher level) + positive (release of intact lower levels); regression mirrors acquisition. | Loss of the general factor; Broca's = Wernicke's + anarthria (Marie); loss of the abstract attitude (Goldstein). | Damage to one sub-component disturbs every function that uses it. |
| Localization stance | Strong localizationism | Holist (graded levels) | Strongest holism | Localizes components, not faculties or connections |
| Strengths | Anatomically grounded; predicts syndromes incl. conduction & repetition patterns. | Ties language to evolution/development; explains automatic-vs-propositional speech & regression. | Captures cross-cutting deficits, the catastrophic reaction, concrete↔abstract behaviour. | Explains why one lesion hits several functions; supports qualitative symptom analysis. |
| Weaknesses | "Diagram-makers"; faculties left unanalyzed; data-rich, theory-poor (Head's "chaos"). | Levels vague & hard to specify; more descriptive than mechanistic. | A single factor can't explain dissociations (anomia vs agrammatism); too undifferentiated. | Localizes components but not their connections; sub-components hard to validate. |
Master aphasia-syndrome table
The classical (connectionist) syndromes. Repetition is the key discriminator: the transcortical syndromes spare it (their lesions fall "off the arc" between the auditory and motor centres); conduction aphasia impairs it most.
| Syndrome | Fluency | Repetition | Comprehension | Naming | Hallmark | Lesion (connectionist) |
|---|---|---|---|---|---|---|
| Broca's | Non-fluent | Impaired | Relatively spared | Impaired | Effortful, telegraphic; agrammatism | Motor word-images (M) — 3rd frontal / Broca's area |
| Wernicke's | Fluent | Impaired | Impaired | Impaired (paraphasic) | Jargon, neologisms; paragrammatism | Auditory word-images (A) — posterior superior temporal |
| Conduction | Fluent | Impaired (worst) | Spared | Mild | Phonemic paraphasias; repetition disproportionately bad | The A–M connection (arcuate fasciculus) |
| Transcortical motor | Non-fluent | Spared | Spared | Impaired | Like Broca's but can repeat; sparse spontaneous speech | Concept→motor connection (above Broca's) |
| Transcortical sensory | Fluent | Spared | Impaired | Impaired | Echolalia; repeats without understanding | Auditory→concept connection |
| Mixed transcortical (isolation) | Non-fluent | Spared | Impaired | Impaired | Only repetition spared (concept field isolated) | Both transcortical connections cut |
| Global | Non-fluent | Impaired | Impaired | Impaired | All modalities lost | A + M (+ connections) — large lesion |
| Anomic | Fluent | Spared | Spared | Impaired | Isolated word-finding deficit | Variable (often temporo-parietal) |
Key contrasts
The high-yield two-way distinctions, gathered in one place. Each links to the chapter that develops it.
Localizationism vs Holism Ch.4 Ch.8
| Localizationism | Discrete functions in discrete places; a lesion removes that function (connectionist diagram-makers). |
| Holism | Function is distributed/general; a lesion produces a graded or general change (Marie, Goldstein, Jackson). |
Agrammatism vs Paragrammatism Ch.15
| Agrammatism | Non-fluent (Broca's); function words & affixes omitted — telegraphic. |
| Paragrammatism | Fluent (Wernicke's); grammatical elements substituted / mis-selected. |
| Grodzinsky | Same locus & basic mis-selection; agrammatism adds a preference for the null element. |
The four acquired dyslexias Ch.14
| Surface | Whole-word route lost → regularization errors (pint→"hint"). |
| Phonological alexia | Non-lexical route lost → can't read non-words; no semantic errors. |
| Deep | Phonological route lost + a semantic deficit → semantic paralexias (close→"shut"). |
| Semantic / "Alzheimer" | Reads irregular words aloud without their meaning. |
Double dissociation: surface (irregular words) ↔ phonological alexia (non-words).
Type vs Token reductionism Ch.1
| Type | Lawful, complete reduction — psychology becomes shorthand for neural states. |
| Token (Fodor) | Each state correlates with some neural state, but with no lawful mapping → psychology is not reducible. |
Access vs Storage deficits Ch.12
| Storage | Knowledge itself is degraded — consistent across trials, frequency-sensitive, no priming benefit. |
| Access | Knowledge intact but retrieval fails — inconsistent across trials, sensitive to priming & rate. |
Verbal vs Literal paraphasia Ch.9
| Verbal | Whole-word substitution; tertiary L parieto-occipital; a first-sound prompt helps. |
| Literal (phonemic) | Sound substitution; secondary L temporal; a prompt does not help. |
Who's who across the book
The names and dates worth attributing in an essay, with their one-line contribution and home chapter.
| Figure | Date | Contribution | Ch. |
|---|---|---|---|
| Broca | 1861 | Motor speech centre in the 3rd frontal convolution; founded localization. | 4 |
| Wernicke | 1874 | Sensory aphasia; auditory word-images; the connectionist model. | 4 |
| Lichtheim | 1885 | The "house" diagram; seven syndromes incl. the transcortical aphasias. | 4 |
| Hughlings Jackson | 1874–8 | Levels of the nervous system; negative/positive symptoms; propositional vs automatic speech. | 7 |
| Jakobson | 1941 | Aphasia as phonological regression mirroring acquisition. | 7 |
| Brown | — | Microgenesis: anterior & posterior level sequences; syndromes as arrests. | 7 |
| Pierre Marie | 1906 | "One true aphasia" = Wernicke's; Broca's = Wernicke's + anarthria. | 8 |
| Dejerine | 1892, 1908 | Marie's opponent in the controversy; alexia with/without agraphia. | 8 |
| Goldstein | 1948 | The "abstract attitude"; the catastrophic reaction. | 8 |
| A. R. Luria | 1947–73 | Process model; the four language processes & their zones. | 9 |
| Geschwind | 1965 | Revived connectionism as disconnection syndromes. | 4 |
| Frege | 1892 | Sense vs reference (the morning/evening star). | 12 |
| Putnam | 1973 | Twin-Earth; the division of linguistic labour. | 12 |
| Rosch | 1975 | Prototypes & the basic-object level (vs classical categories). | 12 |
| Warrington & Shallice | 1979–84 | Category-specific deficits; access vs storage; visual vs verbal semantics (AB/EM). | 12 |
| Marshall & Newcombe | 1973 | Founded the psycholinguistic study of dyslexia; surface vs deep. | 14 |
| Coltheart | 1978–85 | The dual-route model; lexical-decision evidence. | 14 |
| Garrett | 1976–84 | Speech-error model of sentence production (the five levels). | 15 |
| Kean | 1977 | Agrammatism's affected class = phonological clitics. | 15 |
| Grodzinsky | 1984 | Agrammatism & paragrammatism share a locus (Hebrew vowel-tier). | 15 |
Issues running underneath it all
The whole book turns on relating a theory of language to a theory of the brain, and on reductionism, phylogeny, development & pathology — Ch.1.