Ch 4 Neuroanatomy Part II Flashcards
Left hemisphere is dominant for language in what percentage of Right handers
95%
Left hemisphere is dominant for language in what percentage of Left handers
60-70%
Which fissure divides the temporal and frontal lobes?
Sylvian Fissure
Wernicke’s aphasia
disturbance in comprehension (fluent aphasia)
Damage to Broca’s area results in
non fluent aphasia, inability to plan and activate sequence of speech sounds
Repetition of language involves what processes between the Wernicke’s and Broca’s?
phonological representations generated by processing in Wernicke’s area be converted to motor-articulatory sequences and utterances in Broca’s area
What is the name of the pathway that connects the Wernicke’s and Broca’s?
arcuate fasciulus
What is the arcuate fasciulus?
the large subcortical white matter pathway that connects the Wernicke’s and Broca’s areas
What happens if the arcuate fasiculus is damged?
CONDUCTION APHASIA
- disproportionate deficit in repetition, disturbance of spontaneous speech, with relative sparing of comprehension
What are other parts are the Wernicke’s area connected to?
supramarginal and angular gyri of parietal lobe (language comprehension and mapping sounds to meaning)
Which part of the brain is prosody processed?
Right hemisphere
Definition of aprosodia
deficit in comprehending or expressing variations in tone of voice used to express both linguistic and emotional information
Which part of the brain is responsible for expressing emotional prosody in speech
inferior right frontal lobe
Which part of the brain is damaged if someone cannot comprehend emotional prosody
posterior tempoal parietal lesion
Name the deficit of Broca’s aphasia
Impaired speech planning and production
What are the symptoms of Broca’s aphasia?
decreased speech production sparse, halting speech missing function words syntactic deficits right hemiparesis (often)
What is the lesion location of Broca’s aphasia?
third frontal convolution of the inferior frontal gyrus
Name the deficit of Wernicke’s aphasia
Impaired representation of the sound structure of the words
What are the symptoms of Wernicke’s aphasia?
decreased auditory comprehension fluent speech ok paraphasias poor repetition and naming may have right homonymous hemianopia
What is the lesion location of Wernicke’s aphasia?
posterior half of the superior temporal gyrus
Name the deficit of anomic aphasia
impaired storage or access to lexicon
What are the symptoms of anomic aphasia?
decreased single word production
marked for common nouns
repetition and comprehension relative intact
What is the lesion location of anomic aphasia?
inferior parietal lobe or connections within perisylvian language areas
Name the deficit of transcortical motor aphasia
disconnection between conceptual word/sentence representations in perisylvian region and motor speech areas
What are the symptoms of transcortical motor aphasia?
- disturbed spontaneous speech similar to Brocas
- relatively preserved repetition and comprehension
What is the lesion location of transcortical motor aphasia?
deep white matter tracts connecting Broca’s area to parietal and temporal lobe
Name the deficit of transcortical sensory aphasia
disturbed activation of word meanings despite normal recognition of auditorily presented words
What are the symptoms of transcortical sensory aphasia?
Disturbance in word comprehension with relatively inract repetition
What is the lesion location of transcortical sensory aphasia?
White matter tracts connecting parietal and temporal lobe
Name the deficit of conduction aphasia
Disconnection between sound patterns and speech production mechanmisms
What are the symptoms of conduction aphasia?
disturbance of repetition and spontaneous speech, phonemic paraphasia
What is the lesion location of conduction aphasia?
- arcuate fasciculus
- connections between Broca’s and Werrnicke’s area
What is the basal ganglia?
masses of gray matter found deep within the white matter of each cerebral hemisphere.
What are the components of the basal ganglia?
caudate nucleus
putamen
globus pallidus
Functions of the Caudate Nucleus
- controls speed and accuracy of speeded movements
- executive functions (decision making processes related to attention)
- reward and reinforcement
- procedural learning
- inhibition of actions
Functions of Putamen
- regulation of movement
- stored information of previously learned movements
Which two components are included in the striatum?
Caudate nucleus
Putamen
Where is the substantia nigra located?
- midbrain
- has extensive connections to the corpus striatum
Discuss the subcortical loop in the frontal lobe
information is sent from the cortex -> striatum -> globus pallidus –> thalamus –> cortex
Name the loop that explains the frontal-subcortical interaction
Cortico-striatal-pallidal-thalamo-cortical loop
What are the three interconnected systems for attention?
Orientation to stimuli
Alerting
Executive attention
Orientation to stimuli
- tuning of perceptual systems to incoming stimuli so that relevant sensory input can be selected for processing
- dependent on acetylcholine
- involves superior colliculus, pulvinar thalamic nucleus, posterior temporoparietal cortex, frontal eye fields
Alerting
- state of sensitivity to incoming stimuli
- modulated by norepinephrine and depends primarily on ascending sensory inputs from the thalamus
Executive attention
- monitoring and resolving conflicts among thoughts, feelings, behaviors
- dependent on dopamine, anterior cingulate cortex and DLPFC
Working memory anatomic facts
1) distinction between dorsal and ventral systems
2) dorsal components of frontal working memory are preferentially connected to the dorsal visual stream
Which region is activated when doing mental manipulation (e.g. digit sequencing)
Dorsal region
Which region is activated when doing sequential organization and storage (e.g. digit span forward)
Ventral region
