Post on 22-Dec-2015
transcript
Introduction to the Course
Linguistics 411 – Neurolinguistics
Introduction and Course Outline
Basic Brain Anatomy
What this course is about
Linguistic neuroscience• A physical science of language• Unlike ordinary linguistics
o Most ordinary linguistics focuses on things people say – “texts”
• Linguistic neuroscience focuses on the system responsible for texts
The linguistic system of a person A system in the person’s brain
The linguistic system as an object of scientific investigation
It is represented in the brain
• The brain is a physical object Is it observable?
• Indirect observation Aphasiology
• Study of impaired linguistic systems
Study of unimpaired linguistic systems
• Direct observation Functional brain imaging Intra-operative mapping
The start of the investigation
We have to be realistic We have to start with observable phenomena First observation:
• People talk with one another
• They must have some means of doing so
• Call it the linguistic system The linguistic system must have a location
• It is mainly in the cerebral cortex
• Known from aphasiology
Next steps in the investigation
The cerebral cortex is a network
• Very large
• Dynamic Changes take place in connection strengths
The linguistic system is part of the cortex
• Therefore it is a large dynamic network
• Not necessarily all in one part of the cortex In fact, we know it is not We know from aphasiology that it
• Occupies several different cortical regions
• These regions are interconnected
Linguistic neuroscience
Linguistic neuroscience has a direct relationship not only to cognitive science but also to neuroscience• Therefore, to biology
Unlike ordinary linguistics But linguistic neuroscience provides a
bridge from neuroscience to other linguistic pursuits
Quote from Norman Geschwind
I gather … that the status of linguistic theories continues to be a difficult problem. … I would wish, cautiously, to make the suggestion, that perhaps a further touchstone may be added: to what extent does the theory tie in with other, non-linguistic information, for example, the anatomical aspects of language? In the end such bridges link a theory to the broader body of scientific knowledge. (1964)
The need to be realistic
Operational plausibility
• The linguistic system has to be able to operate Developmental plausibility
• The linguistic system has to be able to be built within the brain of a small child
Neurological plausibility
• A theory of the structure of the linguistic system must have a plausible relationship to what is known about the brain from neuroscience
Information Card..
LastName, FirstName email address
Major(s) Class
Previous linguistics courses Previous neuroscience courses Previous cognitive science courses
Languages
Why this course?
The nervous system
Central nervous system
• Spinal cord
• Brain Peripheral nervous system
• Motor and sensory neurons connected to the spinal cord
The brain
Medulla oblongata – Myelencephalon Pons and Cerebellum – Metencephalon Midbrain – Mesencephalon Thalamus and hypothalamus – Diencephalon Cerebral hemispheres – Telencephalon
• Cerebral cortex
• Basal ganglia
• Basal forebrain nuclei
• Amygdaloid nucleus More..
The brain
Medulla oblongata – Myelencephalon Pons and Cerebellum – Metencephalon Midbrain – Mesencephalon Thalamus and hypothalamus – Diencephalon Cerebral hemispheres – Telencephalon
Brain Stem
Alternative partition: Brain stem Cerebellum Thalamus & hypothalamus Cerebral hemispheres
The brain
Medulla oblongata – Myelencephalon Pons and Cerebellum – Metencephalon Midbrain – Mesencephalon Thalamus and hypothalamus – Diencephalon Cerebral hemispheres – Telencephalon
• Cerebral cortex
• Basal ganglia
• Basal forebrain nuclei
• Amygdaloid nucleus
Thalamus and Cortex
We will concentrate on the cortex But the thalamus is also very important
• Relatively neglected
• Too bad! I wish I knew more about it
Metaphor:• The cortex is the orchestra
A very large orchestra • About 30 million members
• The thalamus is the conductor
Also very important: the Basal Ganglia
Major landmarks and the four lobes
Central Sulcus
Sylvian fissure
FrontalLobe
ParietalLobe
TemporalLobe
OccipitalLobe
Primary motor and somatosensory areas
Central Sulcus
Sylvian fissure
Primary Motor Area
Primary Somato-sensory Area
Some terms..
Fissures and sulci
• Singular: sulcus – Plural: sulci
• The major sulci are usually called fissures Interhemispheric fissure Sylvian fissure Sometimes the term Rolandic
fissure is used for the central sulcus Gyri
• Singular: gyrus – Plural: gyri
Alternatives terms for some fissures
Interhemispheric fissure
• Also known as Longitudinal fissure Sylvian fissure
• Also known as Lateral sulcus Central sulcus
• Also known as Rolandic fissure
Primary Areas
Primary Somato-sensory Area
Primary Motor Area
Primary AuditoryArea
PrimaryVisual Area
Divisions of Primary Motor and Somatic Areas
Primary Somato-sensory Area
Primary Motor Area
Primary AuditoryArea
PrimaryVisual Area
Mouth
HandFingers
Arm
Trunk
Leg
Higher level motor areas
Primary Somato-sensory Area
Actions performedby hand
Primary AuditoryArea
PrimaryVisual Area
Mouth
HandFingers
Arm
Trunk
Leg
Actions per-Formed by leg
Actions performedby mouth
Two basic language areas
Primary Somato-sensory Area
Primary Motor Area
Primary AuditoryArea
PrimaryVisual Area
Mouth
HandFingers
Arm
Trunk
Leg
PhonologicalRecognition
PhonologicalProduction
Where is the linguistic system?
Not in one place, but in several interconnected areas
Language involves operations in multiple cortical modalities Each of them may also have
non-linguistic functions The hypothesis of a “language
organ” is implausible