• Subcallosal gyrus
• Cingulate gyrus + Isthmus (of cingulate)
• Hippocampus/parahippocampal gyrus
• Olfactory cortex
• uncus
• amygdala

• Visceral brain
• emotion, motivation, learning, memory

• Frontal cortex/thalamus
• emotion, motivation for survival behaviors
• Prefrontal lobe and hippocampus
• memory and learning
• Amygdala
• agression, mating, stress-mediated responses, memory, feeding, drinking
• Cingulate gyrus
• anxiety and altered behavior
• panic, compulsions, (OCG behaviors)
• Hypothalamus, reticular formation
• ANS; motor aspects of emotion
• fear, flight, sex

Damage to Limbic System:

Etiologies

• Traumatic brain injury
• Dementias/degenerative diseases

Damage to Limbic System:

Symptoms

• uninhibited behavior
• altered sexual behavior
• excessive fear, agression
• altered learning/memory
• altered eating behaviors

• bilateral amygdala damage
• indiscriminate eating, fearlessness, reduced agression, hypersexuality

Reticular formation

General Info

• Network of neurons in brainstem
• Widespread influence
• influences 25,000-30,000 brainstem neurons

Reticular formation:

Afferent connections

• Sensory spinal tracts
• cranial nerves
• cerebellum
• thalamus
• Limbic system

Reticular formation:

Efferent connections

• Somatic and autonomic nuclei; wide-spread CNS regions/structions
• Influence all nervous system functions

Reticular formation:

General functions

• Cortical arousal
• sensori-motor elaboration
• visceral integrated activity

Reticular formation:

Cortical Arousal

• Reticular activating system
• Component of reticular formation
• responsible for cortical arousal and consciousness
• responds to intensity/novelty of stimuli
• insensitive to modality
• lesions to midbrain or midbrain-thalamic junction
• altered levels of conciousness
• drowsiness, stupor, coma

Reticular formation:

Regulation of sensory functions

• Project to sensory processing structures
• accentuate/attenuate stimuli
• general sensory (pain, touch, temperature)
• special sensory (auditory, visual, olfactory)
• pain monitoring/control system

Reticular formation:

Integrated motor functions - List

• Cardiovascular activity
• Respiration
• Swallowing
• Vomiting, coughing

Reticular formation:

Integrated motor functions - Cardiovascular activity

• Regulation of heartbeat, vasomotor function
• Connected to autonomic nervous system

Reticular formation:

Integrated motor functions - Respiration

• Autonomic brainstem respiratory center
• Regulation of respiratory cycle
• Inhalation/exhalation timing based on physical activity and body needs
• Pontine center: duration of inhalation
• Medullary center: respiratory rhythm
• Cortical "take over" for voluntary respiration

Reticular formation:

Integrated motor functions - Swallowing

• Integrating functions of cranial nerves
• Trigeminal, facial, glossopharyngeal, vagus, hypoglossal
• Integrate CN functions with respiratory center
• Regulates reflexive movements in pharyngeal phase of swallow

Reticular formation:

Integrated motor functions - Vomiting, coughing

• Regulate function of required nerves

Reticular formation:

Integrated motor functions - Others

• Autonomic functions
• hypothalamus, thalamus, limbic system
• Biologic rhythms
• hypothalamus, pineal gland
• Self-awareness
• Superior colliculus
• Integrate visual, auditory, somatic stimuli -> 3D image of body in midbrain
• Thalamus = consciousness

• Internal carotid arteries
• from aorta up side of neck
• branches supply anterior, medial and lateral surfaces/structures

• Vertebral arteries
• from aorta up through vertebral column and along brain stem
• fuse to form basilar artery, branch to supply cerebellum, interior and posterior surfaces/structures

• 3 Cerebral arteries
• Anterior
• middle
• posterior
• 2 communicating arteries
• anterior
• posterior

• ACA
• Extends anteriorly
• Feeds mediate surface of R/L hemispheres

• MCA
• Courses laterally through Sylvian Fissure
• Feeds lateral surface of R/L hemispheres

• PCA
• vertebral -> basilar -> posterior cerebral artery
• vertebral arteries (L/R)
• Converge near base of pons
• basilar artery
• branches feed brain stem and cerebellum
• divides into R/L PCA at upper pons
• Posterior Cerebral Artery
• Feeds occipital lobe and inferior temporal lobe

• short, narrow segments that complete the circle of arteries (Circle of Willis)

• ACommA x 1
• Connects R/L ACA

• PCommA x2
• Connect MCA posteriorly to PCA

• Cerebro-Vascular Accident (CVA)
• Transient Ischemic Attack (TIA)

• CVA
• interruption of blood flow to the brian that results in damage to brain tissues

• TIA
• "mini stroke"
• Temporary (transient) arterial blockage

• Ischemic
• Hemorrhagic

• Inadequate blood flow to the brain
• Thrombus: blood clot develops in brain
• Embolus: blood clos develops elsewhere and travels to brain

• blood spills out of vessels
• Intracerebral hemorrhage
• subarachnoid hemorrhage (SAH)
• subdural hemorrhage (SDH)

• Aneurysm
• weakened area of blood vessel

1. MCA
2. ACA

1. Anterior cerebral artery
2. Middle cerebral artery
3. Posterior cerebral artery
4. Posterior cerebral artery
5. Middle cerebral artery
6. anterior cerebral artery

1. Left middle cerebral artery
2. Posterior communicating artery
3. basilar artery
4. internal carotid artery
5. vertrbral artery
6. right common carotid artery
7. external carotid artery
8. anterior communicating artery
9. left anterior cerebral artery

1. Anterior cerebral artery
2. anterior communicating artery
3. Internal carotid artery
4. Superior cereballar artery
5. Basilar artery
6. anterior-inferior cerebellar artery
7. anterior spinal artery
8. vertebral artery
9. Pontine artery
10. Posterior cerebral artery
11. Posterior communicating artery
12. striate artery
13. middle cerebral artery