SLHS 300 FINALLLLL

Brain

Controls thought, sesory perception, emotion, movement and bodily functions (breathing, hormones, heart rate, etc)

Spinal Cord

relays information between the brain and the body (like a highway for information)

Cerebrum

Largest part of the brain

Composed of left and right hemisphere

Responsible for integration of complex sensory and neural functions: touch, vision, hearing, language, reasoning, learning

Initiation and coordination of voluntary activity in the body

Cerebellum

“Little Brain”

Important for motor coordination and prediction

Right hemisphere controls

the left side of the body (contralateral control)

Left hemisphere controls

the right side of the body (contralateral control)

Left Hemisphere functions

Language, verbal memory, symbolic thought, analytical reasoning

Right hemisphere functions

Non-verbal sounds, emotional thought, spatial ability, contect perception, number sequencing

Left Hemisphere function (LANGUAGE)

Speech, word-finding, grammar

Right Hemisphere function (language)

Discourse (coherence, informatively, topicality), metaphors, jokes, prosody

WADA Test

Used to determine which hemisphere is dominant for language

Looks at language and memory function on each side of the brain (one side at a time)

Administration of a drug (sodium amytal) in carotid artery makes one side of the brain inactive

Anterior

Towards the front

Posterior

Towards the back

Inferior

Towards the bottom

Superior

Towards the top

Lateral

Towards the side

Medial

Towards the middle

Sagital

A plane that divides the brain into left and right sections.

Transverse

A plane that divides the brain into upper and lower sections.

coronal

A plane that divides the brain into anterior and posterior sections.

Cerebral Cortex

The outermost layer of the brain, responsible for higher brain functions such as thought, perception, language, memory, attention and motor control

Neurons

Nerve cells in the brain that send and receive messages

Dendrite (cell fingers)

Receives messages from other neurons (where information comes in)

Cell Body (Soma)

Houses the neurons DNA and processes the signal from the dendrites

Axon

Transmits messages to other neurons

Gray matter

Outer surface layer of the brain

Consists mainly of neural cell bodies and dendrites

White matter

Found in deeper tissues of cortex (sub-cortex)

Connects different regions of grey matter

Composed mainly of axons going to the cortex or away from the cortex

Corpus callosum

Bundle of nerve fibers that connects the two hemispheres

Allows the integration of sensory input and functional responses from both sides of the body

Gyrus (Gyri)

The ridges on the cerebral surface of the brain

Sulcus (sulci)

The grooves on the surface of the brain

Sylvian (lateral) Fissure

Grove separating the parietal and frontal lobe FROM the temporal

Central Sulcus

Groove separating the parietal and frontal love

Frontal Lobe

Complex cognitive processes such as planning, reasoning, and problem-solving (executive functions), plan and perform movements (motor control)

Parietal

Receive and process sensory information

Occipital

Process visual information

Temporal

Speech, auditory processing, language comprehension, emotional responses and memory

Brodmanns Area

Mapped out all the different structures of the brain based on anatomical features and cell type associated with specific functions, including sensory and motor control (cytoarchitectonics)

Localization Theory

Specific parts of the brain control different mental function

Holism Theory

Different mental functions are not localized in specific parts of the brain, rather the brain works as a whole and every part of the brain is involved with every cognitive function (need all of the brain, all the time to do anything)

Auditory Cortex

Located in Heschl’s gyrus (frontal lobe), responsible for early processing of sound in both the left and right hemispheres

Broca's area:

Located in the inferior frontal gyrus; responsible for language production, but has other hypothesized roles as well (i.e working memory)

Wernicke's area:

Located in the posterior superior temporal gyrus; responsible for language comprehension but also production

Middle Temporal Gyrus (MTG)

responsible for word meaning

Sylvian parietal temporal (SPT) area:

Responsible for sensory (auditory) motor integration 

Angular Gyrus

Responsible for converting visual stimuli into linguistic stimuli and vice versa 

Motor cortex

Controls speech organ

Electroencephalography (EEG)

Measures when brain activity occurs by recording electrical activity of the brain using sensors placed on the scalp

EEG — N400 Component

A brain response associated with semantic processing and language comprehension

Occurs ~ 400 ms —> when expectations are violated, there is a big N400 response

EEG characteristics

Low spatial resolutions (no localization)

Sensitive to the strength of the signal

Sensitive to muscle movement (eyes, jaws, etc0

Relatively cheap

non-invasive

Intracranial EEG (iEEG)

Follows the same principles as EEG, but electrodes are placed DIRECTLY on the scalp

Higher temporal and spacial resolution than EEG

Very invasive

Magnetic Resonance Imaging (MRI)

Shows structural anatomy of the brain by imaging the gray/white matter and cerebrospinal fluid (CSF)

Uses the magnetic properties of each tissue type to identify tissue in the brain

What do MRIs show us

Used to study of diagnose brain damage, atrophy, neurodegenerative diseases, tumors, identify abnormalities, and relative size of brain structures in different populations 

Functional MRI (fMRI)

A type of MRI that measures brain activity by detecting changes in blood flow (BOLD) —> determines which parts of the brain are active most (indirectly measures neural activity)

High spatial resolution but lower temporal resolution

Magnetic Resonance Imaging (MRI) characteristics

Has high spacial resolution 

Provides clear measures of brain characteristics and pathologies

Very expensive to build the infrastructure and operate 

Sensitive to changes in the magnetic field 

Sensitive to movement

Can be overwhelming for patients

2 structures are important for making connections in the brain

Corpus callosum, arcuate fasciculus

Traumatic Brain Injury (TBI)

Result from the brain hitting the skull or an object piercing the skull and entering the brain tissue

Stroke

A disruption in blood supply resulting in relatively focal death of brain cells

(ischemic stroke — blockage/clot)

(hemorrhagic stroke — bleeding from inside)

Ischemic stroke

Blockage/clot

Hemorrhagic Stroke

Bleeding from the inside

Aphasia

An ACQUIRED language disorder that affects a person's ability to communicate

Left Hemisphere

Which side of the brain is correlated to Aphasia

Broca Aphasia

A type of non-fluent aphasia characterized by difficulty in speech production, while comprehension remains relatively intact

Impaired comprehension for some complex sentences and grammatical structures

Word finding difficulty

Wernickes Aphasia

A type of fluent aphasia where individuals have difficulty understanding language, leading to the production of nonsensical speech while their ability to speak in a fluent manner remains intact

Global Aphasia

non-fluent, impaired comprehension, impaired repetition of words/phrases

Transcortical Motor Aphasia

Nonfluent, relatively good comprehension , good repetition of words/phrases

Conduction Aphasia

Fluent, good comprehension, impaired repetition of words/phrases

Anomic Aphasia

Fluent, good comprehension, good repetition of words/phrases

Transcortical Sensory Aphasia

fluent, impaired comprehension, good repetition of words/phrases

Berko-Gleason Experiment

An experiment demonstrating children's understanding of grammatical morphology through nonsense words, revealing their ability to apply grammatical rules (proof that learning through imitation is false)

Critical Period from Language Acquisition

Humans have a predisposition for language acquisition that begins to dissipate around the age of puberty and falls of grammatically at the onset of adulthood

Statistical Learning

-the use of statistical regularities in language (co-occurrence of phonemes, morphemes and word boundaries) to acquire language

What are the two stages of language development?

prelinguistic and linguistic

Prelinguistic stage

What can kids do before they can talk?
Recognize sounds
Discriminate speech sounds
Segment speech
Identify patterns in their native language
Turn adults into mush!

Linguistic stage: babbling

may be the fist stage of language acquisition

Noises drawn from set of possible human sounds

~6 months infants are able to better control the vocal tract and begin to produce a large variety of sounds

Linguistic: Single-word stage

• ~12 months – babies have begun to segment the continuous speech stream pick out some words, and use them

• Holophrastic sentences: one word to express a whole sentence/message 

  • Examples

    • “Up” → pick me up

    • “Uh-oh” → after an accidence 

    • “Dog” → naming

Linguistic: Two-word stage

• ~2 year old – children start to put words together 

  • Examples

    • Mommy sock

    • Doggy floor

    • Push truck 

Linguistic: Telegraphic Stage

• First utterances longer than 2 words are all missing function words:

  • What that?

  • He play little car

  • Andrew want that

  • No sit there

Consistent morphological order

1. Present progressive (-ing)

2. Prepositions in/on

3. ^^

4. Plurals -s

5. Irregular past tense (e.g said, ran

6. Possessive ‘s

7. Copula, uncontractible (am, is, are, was, were)

8. Articles (a, an, the)

9. Regular past tense -ed

10. 3rd person singular present -s

11. 3rd person singular present, irregular (does, says, has)

12. Auxiliary, uncontractible (am, is, are, was, were)

13. Copula, contractible (‘m, ‘s, ‘re)

14. Auxiliary, contractibel (‘m, ‘s, ‘re)

Mean Length of Utterance (MLU)

• Length is counted in morphemes, not words

  • Examples (how many morphemes?):

    • Doggy eat cookie (3)

    • Doggy eating cookie (4)

    • MLU = 3.5

Browns Stages of Language Development

uses MLU and age to determine whether a child is developing language typically