Telencephalon Foundations

The Telencephalon consists of

• Cortex

• Basal Ganglia

• Lateral ventricles

The cortex consists of

• Frontal lobe

• Parietal lobe

• Temporal lobe

• Occipital lobe

What separates the frontal lobe and parietal lobe from the temporal lobe?

sylvian fissure

what separates the parietal lobe from the occipital lobe?

parieto-occipital lobe

The basal ganglia consists of

• Head of caudate

• Putamen

• Body of caudate

• Nucleus accumbens

• Tail of caudate

• Amygdala

Parkinson’s Disease (PD)

• Degenerative disease of the the ______​

  • Hypokinetic Movement disorder → ______ _______ movement​

• Pathology: Degeneration of _______ neurons in the Basal Ganglia, specifically the ______ _______ of the _______ _______ ​

• Clinical Manifestations → _______ dysfunction​

  • “TRAP” –

• Degenerative disease of the the BG​

  • Hypokinetic Movement disorder → TOO LITTLE movement​

• Pathology: Degeneration of dopaminergic neurons in the Basal Ganglia, specifically the pars compacta of the Substantia Nigra ​

• Clinical Manifestations → Movement dysfunction​

  • “TRAP” – Tremor/Cogwheel Rigidity/Akinesia/Posture

Anatomy of the Ventricles

LATERAL VENTRICLES​​

• _______ (anterior) horn

• ______

• ________ (posterior) horn

• ________ (inferior) horn

THIRD Ventricle​

• _______ _______

FOURTH Ventricle​

• ______ ______

LATERAL VENTRICLES​

• Frontal (anterior) horn​

• Body​

• Occipital (posterior) horn​

• Temporal (Inferior) Horn​

​

THIRD Ventricle​

• Cerebral Aqueduct​

FOURTH Ventricle​

• Central Canal

Lobes of the Cortex: General Function

• Frontal Lobe​

• Parietal Lobe​

• Temporal Lobe​

• Occipital Lobe​

• Frontal Lobe​

  • Movement​

  • Higher order cognition​

  • Decision making and Planning​

• Parietal Lobe​

  • Processing and integration of sensory input​

• Temporal Lobe​

  • Hearing​

  • Learning and Memory​

• Occipital Lobe​

  • Vision

Primary Motor Cortex: AREA ____

• Location:

  • Immediately anterior to ​

• Contains a ​

• _______ Movement Control of the _____ side​

• Source of most neurons in the ____-____ Tract​

• Other areas of the brain are involved in motor planning:​

Primary Motor Cortex: AREA 4

• Location: Pre-Central Gyrus (Frontal Lobe)​

  • Immediately anterior to Central Sulcus​

• Contains a Complex map of the body​

• Voluntary Movement Control of the opposite side​

• Source of most neurons in the Cortico-Spinal Tract​

• Other areas of the brain are involved in motor planning:​

  • Supplementary motor area​

  • Premotor area

Primary Motor Cortex: Function

• Controls _______ Movement​

  • _______ b/c the tract crosses the midline​

  • Skilled, precise _____ of distal limb muscles

  • Control of the lower portion of the _____​

  • More neurons devoted to _____/____ than the rest of the body (trunk, LE’s )​

• Controls _____ and _____ of movement

• Controls Voluntary Movement​

  • Contralateral b/c the tract crosses the midline​

  • Skilled, precise control distal limb muscles, especially the flexors of the hand​

  • Control of the lower portion of the face ​

  • More neurons devoted to hand/face then the rest of the body (trunk, LE’s )​

• Controls force and speed of movement

AREA ____: Pre-Motor AND Supplemental Motor Cortices

• Location: ​

  • Anterior to the Pre-central Gyrus (Frontal Lobe) ​

    • (ANTERIOR to Primary Motor Area)​

  • PRE-MOTOR: _____ portion of AREA ___​

  • SUPPLEMENTAL MOTOR: _____ portion of AREA ___

• Function:

  • Use of ______ and other sensory inputs to generate movement​; relies on ______

    • Orientation of a ______ → especially _____, to a target​

    • Planning ________ and _____ movements​

  • Movement that is more _____ than automatic

  • Orientation of the _____/_____​

AREA 6: Pre-Motor AND Supplemental Motor Cortices

• Location: ​

  • Anterior to the Pre-central Gyrus (Frontal Lobe) ​

    • (ANTERIOR to Primary Motor Area)​

  • PRE-MOTOR: Inferior portion of AREA 6​

  • SUPPLEMENTAL MOTOR: Superior portion of AREA 6

• Function:

  • Use of vision and other sensory inputs to generate movement;​ relies on context

    • Orientation of a limb → especially hand, to a target​

    • Planning Bimanual and sequential movements​

  • Movement that is more planned than automatic

  • Orientation of the eyes/head​

Area 6: Some differences

• Pre-motor

  • NEEDS ______ Input to function​

  • Activates ______ muscles​

  • _____% of the CST arises from here

• Supplemental motor

  • Mental Rehearsal takes place here → ______ sequences live here​

  • Activates ______ muscles​

  • NO _______ _______ arises from here

• Pre-motor

  • NEEDS Sensory Input to function​

  • Activates PROXIMAL muscles​

  • 30% of the CST arises from here

• Supplemental motor

  • Mental Rehearsal takes place here → Learned sequences live here​

  • Activates DISTAL muscles​

  • NO descending pathway arises from here

Frontal Eye Fields: Area _____

• Located anterior to ________ _______ ________

• Involved in _______ _______ _______ (especially _______) and ________ of the pupils​

• Activated by ______ Stimuli​

• Notice the overlap of the frontal eye fields → ____-_____ ______ and ______ _____ ______

• Located anterior to Supplemental Motor Cortex​

• Involved in conjugate eye movement (especially saccades) and constriction of the pupils​

• Activated by visual Stimuli​

• Notice the overlap of the frontal eye fields → Pre-motor cortex and PFC

Primary Sensory Cortex: AREA ___,___,___

• Location: _____ ______ ______​

  • Immediately posterior to _____ _____

• Identifies the ______ of stimuli and discriminates among various _____, _____ and _____ of objects

• Location: Post Central Gyrus (Parietal Lobe)​

  • Immediately posterior to Central Sulcus​

• Identifies the location of stimuli and discriminates among various shapes, sizes and textures of objects

Primary Visual Cortex: AREA ____,____,____

• Location: ______ Lobe​

  • Immediately posterior to ______-_____ Sulcus​

• Receives and interprets all _____ input​

• In general, information from the _____ side of the world goes to the _____ side of the brain​

Primary Visual Cortex: AREA 17, 18, 19

• Location: Occipital Lobe​

  • Immediately posterior to Parieto-occipital Sulcus​

• Receives and interprets all visual input​

• In general, information from the LEFT side of the world goes to the RIGHT side of the brain​

Primary Auditory Cortex: Area 41, 42

• Located in the ______ Lobe​

• Closely associated with _____ Area and _____ Area

• The ______ hemisphere is considered the ______ hemisphere for Language​

  • So, although there is an Auditory Cortex on BOTH sides, the _____ is “more active”​

  • Lesions to the _____ hemisphere produce more severe language disorders

• Located in the Temporal Lobe​

• Closely associated with Wernicke’s Area and Broca’s Area

• The LEFT hemisphere is considered the DOMINANT hemisphere for Language​

  • So, although there is an Auditory Cortex on BOTH sides, the LEFT is “more active”​

  • Lesions to the LEFT hemisphere produce more severe language disorders

Broca’s area: ____,____

• Area of ________

Broca’s area: 44,45

• Area of expression

Wernicke’s area: _____

• Area of _____

  • _____/_____

Wernicke’s area: 22

• Area of reception

  • speech/language

Somatosensory association area: ____,____

• Location: ______ ______ ______; just posterior to _____ ______ cortex​

• Function: Integrates _____ info and gives _______

Somatosensory association area: 5,7

• Location: Superior Parietal Lobule; just posterior to primary sensory cortex​

• Function: Integrates sensory info and gives meaning

Pre-Frontal Cortex (PFC): Areas ___-___

• ______ association area in the Frontal Lobe​

• Involved in _____ ____ mental functions​

• Has ___-______ connections all over the cortex and sub-cortical

Pre-Frontal Cortex (PFC): Areas 9 - 12

• Largest association area in the Frontal Lobe​

• Involved in higher order mental functions​

• Has bi-directional connections all over the cortex and sub-cortical

Blood supply to the brain

• 2 pairs of arteries that carry blood to the brain​

  • _____ Carotid Arteries → _____ Blood Supply​

  • _____ Arteries → Join together to form → ______ Artery → ______ blood supply

• 2 pairs of arteries that carry blood to the brain​

  • Internal Carotid Arteries → Anterior Blood Supply​

  • Vertebral Arteries → Join together to form → Basilar Artery → Posterior blood supply

• Carotid and Vertebrobasilar system → Join to form the ______ of ______​

  • _____ of _____: circulatory _______ that supplies blood to the brain​

• Main Arteries that Supply the Brain​

  • _______,______, and ______ cerebral​

• Internal Carotid → Primary source for ______ and ______ Cerebral​

• Vertebrobasilar → Primary source for ______ Cerebral​

• ______ and ______ Communicating arteries complete the Circle

• Carotid and Vertebrobasilar system → Join to form the Circle of Willis​

  • Circle of Willis: circulatory anastomosis that supplies blood to the brain​​

• Main Arteries that Supply the Brain​

  • Anterior, Middle and Posterior Cerebral​

• Internal Carotid → Primary source for Anterior and Middle Cerebral​

• Vertebrobasilar → Primary source for Posterior Cerebral​

• Anterior and Posterior Communicating arteries complete the Circle

Anterior Cerebral Artery

• Anterior/Medial Surface of the Cortex - ______ and ______ Lobes​

• ______ ______

• Common Characteristics of ACA Occlusion​

  • Contralateral hemiparesis, ____ > ____​

  • Contralateral sensory loss, ____ > ____​

  • _______ ______

  • Problems with _______ _____ (BG)​

• Occlusion of the ACA is rare and makes up only about ___% of all CVA’s

Anterior Cerebral Artery

• Anterior/Medial Surface of the Cortex - Frontal and Parietal Lobes​

• Basal Ganglia​

• Common Characteristics of ACA Occlusion​

  • Contralateral hemiparesis, LE > UE​

  • Contralateral sensory loss, LE > UE​

  • Urinary incontinence​

  • Problems with bimanual tasks (BG)​

• Occlusion of the ACA is rare and makes up only about 2% of all CVA’s

• ______ lobe and Medial/Inferior ______ Lobe​

• Upper ____ and most of _____ ​

• Common Characteristics of PCA Occlusion​

  • Contralateral _________ _______​

  • Prosopagnosia – difficulty…..​

  • _____ deficits​

  • ______​

  • Contralateral _______

• Occipital lobe and Medial/Inferior Temporal Lobe​

• Upper BS and most of Thalamus ​

• Common Characteristics of PCA Occlusion​

  • Contralateral Homonymous hemianopsia​

  • Prosopagnosia – difficulty naming people on site​

  • Memory deficits​

  • Dyslexia​

  • Contralateral hemiplegia

Middle Cerebral Artery

• MCA often branches and forms at least two and up to _____ branches​

• Most common: ______ and _____ Divisions​

• Supplies the cortex, on both sides if the Sylvian fissure, including lateral ______ lobe and parts of the ______ lobe and parts of the _____

• Most common occlusion is MCA due to its ____ and ____

• MCA often branches and forms at least two and up to five branches​

• Most common: Superior and Inferior Divisions​

• Supplies the cortex, on both sides if the Sylvian fissure, including lateral temporal lobe and parts of the parietal lobe and parts of the BG (most of caudate)​

• Most common occlusion is MCA due to its size and location

MCA Occlusion

• Dominant Hemisphere

  • Contra lateral _____ (____ > ____)​

  • Contra lateral _____ loss​

  • ______

• Non-dominant hemisphere

  • Contra lateral ______ (____ > ____)​

  • Contra lateral _____ loss​

  • H________ H______

  • _______ deficits (_____-_____)

• Dominant Hemisphere

  • Contra lateral hemiplegia (UE > LE)​

  • Contra lateral sensory loss​

  • Aphasia

• Non-dominant hemisphere

  • Contra lateral hemiplegia (UE > LE)​

  • Contra lateral sensory loss​

  • Homonymous Hemianopsia​

  • Perceptual deficits (Hemi-neglect)

Vertebrobasilar Artery

• Supplies the ______ portion of the Brain​

• Specifically supplies the _______ and ______

• Occlusions within the system cause a variety of symptoms the most common being “______ ___ ______”​

• Accounts for a very _____ number of CVA

Vertebro-Basilar Artery

• Supplies the Posterior portion of the Brain​

• Specifically supplies the cerebellum and brainstem​

• Occlusions within the system cause a variety of symptoms the most common being “locked in syndrome”​

• Accounts for a very small number of CVA

Cerebellar Arteries

• All CB arteries exit from the ______ ______​

• 3 main arteries:​

  • ______ _______ _______ (SCA)​

  • ______ _______ ______ _____(AICA)​

  • ______ _______ ______ ______ (PICA)

Cerebellar Arteries

• All CB arteries exit from the Basilar Artery​

• 3 main arteries ​

  • Superior Cerebellar Artery (SCA)​

  • Anterior Inferior Cerebellar Artery (AICA)​

  • Posterior Inferior Cerebellar Artery (PICA)