Neuroanatomy and Neurophysiology: Key Concepts for Medical Students

What could loss of only pain and temperature from one half of the face be due to?

A lesion of the lateral medulla.

Which fibers are responsible for fast pain?

A delta.

What do otic ganglion fibers release?

Ach mediated by muscarinic receptors.

What tumor is indicated by a patient presenting with loss of hearing on the right and nystagmus?

Cerebellar pontine angle tumor.

Which deep sensibility modality is excluded?

Pinprick.

What do preganglionic sympathetic fibers release?

Ach mediated by nicotinic receptors.

What may result from a lesion of the medial lemniscus?

Loss of vibration senses.

What is positioned between the medial geniculate body and the superior brachium?

Pulvinar.

Which fibers are most myelinated?

A alpha.

Which cranial nerves arise from the pons?

5, 6, 7, 8.

Does the posterior pituitary receive antidiuretic and oxytocin hormones from the hypothalamus?

True.

Where are fibers carrying conscious and unconscious proprioception from the upper limbs found?

Fasciculus cutaneous.

What causes hyperpolarization during an action potential?

Potassium ion efflux.

Which fibers carry slow pain information?

C fibers.

Where does the deep sensibility pathway decussate?

Medulla.

What is the main inhibitory neurotransmitter of the cerebrum?

GABA.

Is synaptic potential the temporal and spatial summation of excitatory and inhibitory postsynaptic potentials?

True.

Which thalamic nucleus lesion decreases rigidity and tremors (Parkinson’s)

Ventral anterior and ventral lateral

What is the connection between the inferior brachium and the inferior colliculus?

Medial geniculate body.

Which thalamic nucleus receives fibers from the trigeminal lemniscus?

VPM.

Where are first order neurons mediating proprioception from the face located?

Mesencephalic nucleus.

Where are the second order neurons for the pathway for pain and temperature from the face located?

Nucleus of spinal tract of trigeminal.

What do preganglionic parasympathetic fibers release?

Ach mediated by nicotinic receptors.

What may result from a lesion of the superior parietal lobule? Non dominant side

Neglect syndrome.

What may result from a lesion of the superior parietal lobule? dominant side left (left angular gyrus)

gertsman syndrome

Acaculia, agraphia, right left disorientation, finger agnosia

Which thalamic nucleus does the lateral spinothalamic tract synapse in?

MPL

Where is the gustatory cortex located?

Insula.

Where are the cell bodies of the postganglionic sympathetic fibers that supply peripheral blood vessels?

Paravertebral.

Where are the cell bodies of the dorsal spine cerebellum tract located?

Ipsilateral Clarke's column / nucleus dorsalis.

Where is Broca's area usually found?

Left inferior frontal gyrus.

What does central hyperalgesia refer to?

A decrease in the activation threshold of the nucleus proprius.

What would a patient with a peripheral nerve injury suffer from?

Hyporeflexia.

What does the facial nerve supply?

Facial expressions.

Where is the lower limb representation of the motor cortex located?

Anterior portion of the paracentral lobule.

What do greater splanchnic nerve fibers release?

Ach mediated by nicotinic receptors.

Which function is not a function of the hypothalamus?

Visual reflex.

What would a patient with peripheral nerve injury present with?

Hyporeflexia.

What results from a lesion of the lateral spinothalamic tract at T10?

Contralateral loss of pain and temperature from T10 down.

Lesion of fasciculus gracious in the cervical cord could result in loss of the following modalities except ?

propricoeption of upper limbs

Which functional system does the stria medullaris thalami belong to?

Epithalamus.

What may prosopagnosia be a symptom of?

A lesion of the fusiform gyrus /occipitotemporal gyri

What do cardiac plexus fibers from the inferior cervical ganglion release?

Ach. and NE which increase HR

Where are the cell bodies of the postganglionic sympathetic fibers that supply abdominal viscera located?

Prevertebral.

What could a hemisection of the spinal cord affecting the dorsal columns at C7 result in?

Loss of vibration and spastic paralysis on the right from C7 down, loss of pain on the left from T1 down.

Which thalamic nucleus receives fibers originating from the dentate nucleus?

Ventral anterior and ventral lateral.

What symptom combinations indicate a spinal cord hemisection?

Ipsilateral vibration. Dissociated sensory loss

What is responsible for the falling phase of an action potential?

Potassium ions leaving.

What results from a lesion of the ventral white commissure of the eighth cervical segment of the spinal cord?

Bilateral loss of P&T at T2.

A patient presents with loss of hearing on the right and nystagmus, imaging reveals a tumor?

Vestibular stroma can VIII vestibulocochlear