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notes/courses/LING-UA-1/15-neurolinguistics.md

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+---
+title: Neurolinguistics
+date: 2025-06-17
+---
+
+# Neurolinguistics
+
+## What is Newrolinguistics?
+
+### Human brain - crash course
+- two hemispheres
+  - each into four lobes
+    - Frontal lobe (Executive functions such as attention, planning, decission making)
+    - Temporal lobe (Language, auditory processing)
+    - Parietal lobe (Spatial cognition, sensory information)
+    - Occipital lobe (Vision)
+
+The role of lobes may be similar across hemispheres, there are also hemispheric differences, called **lateralization.**
+- Split-brain patients providesome evidence for this.
+
+## Aphasia and the origin of neurolinguistics
+
+### How to study language before neuroimaging
+Study impaired language, as different types of **apahsias**. Aphasia arises from brain damage of some sort, common causes include:
+- Stroke
+- Traumatic brain injuries
+- Neurodegenerative diseases
+- Resective surgery (to treat epilepsy)
+
+Rationale is known as the **deficit-lesion method**.
+- Logic: If the individual cannot do X behavior, then the execution of X must depend on the lesioned area.
+- Questions: Moral questions, conclusion
+
+### Broca's aphasia
+Paul Broca and the patient "Tan" (1861)
+- Broca's area
+
+Characteristics of Broca's aphasia:
+- Slow, laborious, non-fluent speech with few if any grammatical morphemes.
+- Comprehension relatively intact, but writing is limited.
+
+### Fluent (Wernicke's) aphasia
+Carl Wernicke's subsequent discovery (1874)
+
+Characteristics of Fluent (Wernicke's) aphasia:
+- Fluent but disordered speech and writing.
+- Frequent substitutions of real words with nonsense words.
+- impaired understanding of speech and writing.
+
+### How much can we learn from aphasias
+Get an idea of where and how language is organized in the brain by comparing behavior and lesson sites. Many disadvantages of relying on apasia studies:
+- Inter-individual variability, no patients are identical, and difficult to replicable.
+- Lot of reorganization can happen during recovery.
+- Moral concerns.
+
+## Modern neuroimaging techniques
+
+### Overview of modern neuroimaging techniques
+To investigate what the brain does, whare it does it, and when it does it.
+- Structural imagining (measuring the structure of the brain)
+- Functional imagining (measuring an aspect of brain function)
+  - Non-invasive techniques (PET, fMRI, EEG, MEG etc.)
+  - Invasive techniques (electrocorticography, single cell recordings)
+
+### Hemodynamic techniques (PET & fMRI)
+Measure blood, a dependent measure of neural activity
+- PET: Positron Emission Tomography
+- fMRI: Functional Magnetic Resonance Imagining
+
+Increase in neuronal activity -> Increase in metabolic demand for glucose and oxygen -> Increase in cerebral blood flow to the activated region
+
+Measures the work of the brain after it has happened.
+Hemodynamic techniques have excellent spatial resolution but bad temporal resolution.
+
+### Electrophysiological techniques (EEG & MEG)
+Measure actual electrical activity of neurons
+- EEG: Electroencephalography
+- MEG: Magnetoencephalography
+
+Neurons use electricity to communicate with each other -> Neuronal networks fire in synchrony -> the correlates of this combined electrical activity can be measured
+
+Measures the work of the brain as it is happening
+Electrophysiology conditions
+
+## Some classic and modern findings
+
+### Case studies
+- Using modern neurolinguistics
+
+#### Phonemes in the brain
+Phillips et al. (2000): Does auditory cortex have access to phonemic categories? And when is phonemic category information accessed? 
+
+Major Obstacle: To prove that any results are due to crossing a phoneme boundary rather than just differeces in the acoustics?
+
+Approach:
+Examine the **Auditory Mismatch Field** elicited in auditory cortex at ~180ms post stimulus onset by deviant stimuli in an **oddball paradigm**.
+
+Conclusion: Auditory cortex has access to phonemes, not just acoustic features, and they are recognized quickly.
+
+#### Semantics and syntax in the brain
+Finding evidence for high-level processes? (higher than phonemes)
+
+So called **violation studies** use EEG has investigated brain responses to when languages goes awry.
+
+N400: Semantic anomalies. (negativity 400 ms after the stimulus onset)
+P600: Syntactic anomalies. (positivity 600 ms after the stimulus onset)
+
+Progression from smaller unit to larger unit in terms of time.
+
+#### Putting two words together
+Combining two lexical items involves at least three processes
+- Syntactic composition
+- Logico-semantic composition (properties combine to to form set of entities)
+- Conceptual composition (features combine)
+
+What aspects of composition is the brain sentitive to?
+
+Bemis & Pylkäanen(2011)
+
+- two words vs. one word
+  - Consonant string vs. psuedoword
+- Task (picture matching)
+- Composition  vs. List
+  - To account for the visual presence of two words
+  - Task varied for composition and list stimuli to avoid composition
+
+Significant results, difference from two-word composition and one-word composition.
+
+Reflect conceptual composition!
+

notes/courses/LING-UA-1/index.json

@@ -44,6 +44,12 @@
     {
         "slug": "14-psycholinguistics",
         "title": "14 - Psycholinguistics",
-        "date": "2025-06-13"
+        "date": "2025-06-16"
+    }
+    ,
+    {
+        "slug": "15-neurolinguistics",
+        "title": "15 - Neurolinguistics",
+        "date": "2025-06-17"
     }
 ]