Thalamocortical Pathways and Ascending Arousal System

What type of neurons modulate the responses of other thalamic neurons to input from the cortex?

Thalamic interneurons

What is the term used for the recording obtained with electrodes on the pial surface of the cortex?

Electrocorticogram

What is the EEG recorded from the scalp a measure of?

Dendritic postsynaptic potentials

What is the orientation of the dendrites of cortical neurons in the superficial layers of the cerebral cortex?

Similarly oriented Signup and view all the answers

What kind of potentials can be generated in dendrites?

Propagated potentials Signup and view all the answers

What is the relationship between the cell body and dendrites?

Shifting dipole Signup and view all the answers

What is the primary function of the thalamus in relation to the cerebral cortex?

It processes virtually all information that reaches the cortex. Signup and view all the answers

What happens when the sum of the dendritic activity is negative relative to the cell body?

The neuron is depolarized Signup and view all the answers

Which of the following thalamic nuclei receive input from the basal ganglia and project to the motor cortex?

Ventral anterior and ventral lateral nuclei Signup and view all the answers

What is the consequence of current flow in the shifting dipole?

Wavelike potential fluctuations Signup and view all the answers

What is the primary function of the thalamic reticular nucleus?

It provides inhibitory inputs to other thalamic neurons. Signup and view all the answers

Which neurotransmitter is released by most thalamic neurons?

Glutamate Signup and view all the answers

What is the function of the anterior nuclei of the thalamus?

They receive input from the mammillary bodies and project to the limbic cortex to influence memory and emotion. Signup and view all the answers

What is the function of the medial and lateral geniculate bodies?

They relay auditory and visual impulses to the auditory and visual cortexes, respectively. Signup and view all the answers

Which thalamic nuclei project diffusely to wide areas of the neocortex?

Midline and intralaminar nuclei Signup and view all the answers

What is the function of the ventral posterior lateral and ventral posteromedial nuclei?

They relay sensory information from the body to the postcentral gyrus. Signup and view all the answers

What happens to a neuron when it is positively charged?

It becomes less excitable Signup and view all the answers

What is the main characteristic of epilepsy?

Recurring, unprovoked seizures Signup and view all the answers

What is the term for the time after a seizure until normal neurologic function returns?

Postictal period Signup and view all the answers

What is the main difference between partial and generalized seizures?

Location of seizure origin Signup and view all the answers

What is an example of a simple partial seizure?

Localized jerking movements in one hand Signup and view all the answers

What is the term for abnormal sensations that precede the onset of a partial seizure?

Auras Signup and view all the answers

What is the main characteristic of generalized seizures?

Widespread electrical activity involving both hemispheres Signup and view all the answers

What is the term for seizures that are divided into convulsive and non-convulsive categories?

Generalized seizures Signup and view all the answers

What is a significant difference in brain composition between healthy individuals and those with narcolepsy?

Quantity of hypocretin producing neurons in the hypothalamus Signup and view all the answers

What is the primary cause of daytime sleepiness in obstructive sleep apnea?

Frequent episodes of upper airway obstruction Signup and view all the answers

What is a characteristic of an individual with OSA during sleep?

Progressively louder snoring until apnea Signup and view all the answers

What is the estimated percentage of middle-aged men in the United States affected by OSA?

24% Signup and view all the answers

What is a key factor in the pathophysiology of OSA?

Reduced neuromuscular tone at sleep onset Signup and view all the answers

What is a consequence of OSA on sleep patterns?

Increased time spent in Stage 1 non-rem sleep Signup and view all the answers

What is the typical response of an individual with OSA when an episode of apnea occurs?

Loud snort and gasp Signup and view all the answers

What is the estimated percentage of women in the United States affected by OSA?

9% Signup and view all the answers

What is the characteristic pattern of activity associated with absence seizures?

3/s doublets with a typical spike and wave pattern Signup and view all the answers

What is the primary sleep disorder characterized by a sudden loss of voluntary muscle tone?

Narcolepsy Signup and view all the answers

What is the typical duration of a spike and wave pattern in absence seizures?

10 seconds Signup and view all the answers

What is the prevalence of narcolepsy in Americans?

1 in 1,000 Signup and view all the answers

What is the genetic susceptibility associated with narcolepsy?

Class 2 antigen of the major histocompatibility complex Signup and view all the answers

What is the typical sleep pattern in individuals with narcolepsy?

REM sleep followed by non-REM, slow wave sleep Signup and view all the answers

What is the function of the HLA complexes in the immune system?

Regulation of the immune system Signup and view all the answers

What is the term for the brief episodes of total paralysis that can occur at the beginning or end of sleep in individuals with narcolepsy?

Sleep paralysis Signup and view all the answers