Basic Mechanisms Underlying Seizures and Epilepsy

Epilepsy is
1. the the sequence of events that turns a normal neuronal network into a hyperexcitable
  network.
2. a disorder of the central nervous system characterized by recurrent seizures unprovoked by an acute systemic or neurologic insult.
3. synonymous with a single seizure.
4. characterized by recurrent provoked seizures.
The hippocampus consists of three major regions: subiculum, hippocampus proper (Ammon’s horn) and dentate gyrus. Which of the following is correct.
1. The hippocampus has a six layered cortex.
2. The dentate gyrus has a six layered cortex.
3. The subiculum is the transition zone from the three to the six layered cortex.
4. The hippocampus is part of the parietal lobe.
The cortex has two general classes of neurons; principal neurons and interneurons. Choose the correct statement from the following.
1. Interneurons generally project to neurons located in distant areas of the brain.
2. Principal neurons are generally considered to be local-circuit cells which influence the activity of nearby neurons.
3. Most principal neurons form inhibitory synapses on principal cells or other inhibitory neurons while most interneurons form excitatory synapses on post-synaptic neurons.
4. Recurrent inhibition can occur when a principal neuron forms synapses on an inhibitory neuron, which in turn forms synapses back on the principal cells to achieve a negative feedback loop.
A hyperexcitable state conducive to triggering a seizure can result from
1. Increased excitatory neurotransmission.
2. Decreased inhibitory neurotransmission.
3. Alteration in voltage-gated ion channels
4. All of above.
Which of the following glutamate receptors is blocked by the Mg++ ions in the resting state, but becomes permeable to Ca++ under conditions of local membrane depolarization?
1. AMPA channel
2. NMDA channel
3. Kainate channel
4. Metabotropic glutamate receptor
Barbiturates and benzodiazepines suppress seizure activity through the mechanism of
1. Blocking NMDA receptor
2. Blocking AMPA receptor
3. Blocking GABA-A receptor
4. Facilitating GABA-A receptor
The EEG waveforms are divided into four major frequency bands. The theta frequency ranges from
1. 0-4 Hz
2. 5-7 Hz
3. 8-13 Hz
4. 40 Hz
Electroencephalogram (EEG) is a recording of the electrical activity of the cerebral cortex. Considering the electrical activity of a single pyramidal neuron, the term "SINK" refers to
1. the inward current at the synapse resulting from positively charged ions rushing into the cell trigggered by an incoming excitatory signal.
2. outward current across the cell membrane at sites distant from the synapse.
3. a dipole outside the dendrite.
4. the synchronous activation of the pyramidal neurons.
Which of the following changes can be observed on the EEG with eye opening or mental alerting activities.
1. Amplitude increase
2. Frequency increase
3. Amplitude decrease
4. Frequency decrease
Which of the following statement about Kindling is correct?
1. Kindling requires daily, subconvulsive stimulation.
2. The changes in excitability seen with kindling are short lived.
3. Kindling requires daily, supramaximal convulsive stimulation.
4. Kindling is an excellent model for absence seizures.

Basic Mechanisms Underlying Seizures and Epilepsy

Quiz