Neuroscience Week 5: Brainstem Flashcards
The Reticular Formation It consists of centers that
7 listed
- Integrate cranial nerve reflexes
- Help conduct and modulate SLOW pain
- Influence voluntary movements
- Regulate autonomic nuclei
- Associate with diffuse modulating systems
- Integrate sleep and respiration
- ACTIVATE the cerebral cortex
Which sensory systems provide input to the reticular formation?
Almost all of them
Reticular Formation inputs
Ascending reticular activating system
Locus Coeruleus
the major source of noradrenergic innervation to all cortical regions
Raphe Nuclei
diffuse serotonergic innervation and involved in alertness and wakefulness
Basal forebrain
- Cholinergic innervation, originate in the nucleus of Meynert of the basal forebrain
- thought to degenerate in Alzheimer’s Disease
Ventral Tegumental Area
- Dopaminergic innervation of the cerebral cortex
- arises from Ventral tegmental area and projects to aspects of the limbic system
- such as the cingulate gyrus and prefrontal cortex
- awareness, alertness, motivation
Widespread projection systems in the nervous system
Orexin system
- many functions but promote wakefulness and reward pathways
- enhance dopamine signaling that can trigger incentive or reward
- can modulate ARAS and therefore modulate wakefulness and alertness
Histaminergic Neurons
- The tubomammilary nucleus of the hypothalamus can also control cortical activity and promote alertness
- can remember by thinking of benadryl which makes you drowsy if you take it
Recap of Aras
numerous roles
Importance of ARAS
Bilateral inactivation of the pontomesencephalic reticular formation, thalamus and the cerebral cortex results in?
Coma
Brainstem Reticular Formation consists of centers that
7 Listed
ARAS Originates
midbrain and upper pons
ARAS is responsible for?
- arousal
- attention
If cortex presses down on the brainstem can cause
- Coma if ARAS is being pressed on
- Particularly with Uncal Herniation
Blood supply to the brainstem
Identify region and blood supply
Identify region and blood supply
Identify region and blood supply
Identify region and blood supply
Identify blood supply
Identify brainstem anatomy
Identify region, contents, anatomy and blood supply
Cervicomedullary junction
Trigeminal spinal pathway
- 1st neuron trigeminal ganglion in upper pons
- 2nd order is trigeminal caudal nucleus in caudal medulla and spinal cord
- decussates
- ventroposteriolateral thalamus
- Sensory cortices
Trigeminal Pathway
Identify region, contents, anatomy and blood supply
Caudal (lower) Medulla
Identify region, anatomy, blood supply and describe medial medullary syndrome
Identify region, contents, anatomy and blood supply
Rostral (upper) Medulla
Identify region, anatomy, blood supply and describe Lateral medullary syndrome
Identify region, contents, anatomy and blood supply
Caudal to mid Pons
Identify region, anatomy, blood supply and describe medial pontine syndrome
Identify region, anatomy, blood supply and describe Lateral pontine syndrome
Identify region, contents, anatomy and blood supply
Full Basilar Stroke AKA
Locked-in syndrome
Identify region, anatomy, blood supply and describe Locked-in Syndrome
Identify region, contents, anatomy and blood supply
Caudal midbrain
Identify region, contents, anatomy and blood supply
Rostral Midbrain
Identify region, anatomy, blood supply and describe Weber’s Syndrome
Identify Syndromes associated with various arteries
Identify arteries associated with various syndromes
Identify arteries and associated syndromes
Map of cranial nerve nuclei
Red nucleus lesion in the midbrain
Tremor and ataxia because you cannot finetune your movements
Cerebral peduncle lesion in the midbrain will cause
UMN lesion in the face and lower extremities
MLF lesion in the midbrain will cause
horizontal gaze palsy
Benedikt Syndrome identify where the lesion is and effects
Benedikt Syndrome structures affected
Red nucleus
CN 3
Medial lemniscus
Weber Syndrome identify lesion location and effects
Describe Pseudobulbar palsy
Parinaud syndrome identify lesion location and effects
Identify structures and which segment
Pons vestibular nuclei lesion effects
4 listed
- nausea
- vomiting
- nystagmus
- vertigo
Pons CN VII Tract lesion
- facial droop
- loss of corneal reflex
Pons Medial Lemniscus Lesion
- loss of proprioception
- loss of vibration
Pons Corticospinal tract Lesion
contralateral Hemiparesis