Test 1 Study Guide Part 5 Flashcards
Central sulcus separates:
Parietal and frontal lobe
Precentral Gyrus:
Motor control (upper motor neurons) Which the frontal lobe is in charge of
Postcentral Gyrus:
Sensory (somatosensory) in the temporal lobe which is in charge of somatosensory
Name all voltage gated Na+ channel blockers (which effect Action potentials):
Lidocaine
Cocaine
Saxitoxin
Tetrodotoxin
Broca’s area:
Broca area is the motor speech area
Broca and motor have the same number of letters, since it is motor it is in the frontal cortex
- Frontal lobe
- Left side
Wernicke’s area:
Sensory interpretive area,
this spans temporal and parietal lobes, which all have a sensory emphasis. Also found in the left hemisphere
In terms of sensory and motor neural emphasis is on which regions:
Face and hands
Mirror neurons:
- Origin:
- Regions they are interconnected with:
- Possible implication of their failure:
- Origin:
Nerves of the parietal and frontal cortex - Regions they are interconnected with:
insula - Possible implication of their failure:
Lack of empathy (and learning?) in autism spectral disorder
EEC readings: Alpha: Beta: Theta: Delta:
Alpha: Associated with relaxed awake adults, eyes closed. Parietal -> occipital
Beta: Frontal lobe. Associated with visual stimuli and mental activity
Theta: common in sleeping adults or awoken children
Emitted from Temporal and occipital lobes. If seen in awake adults it is indicative of emotional stress and a severe nervous breakdown
Delta: Cerebral cortex as a whole, common during adult sleep and for awake infants. Delta waves in an awake adult indicate brain damage (dumb, delta, disorder, damage)
Neurotransmitters which promote wakefulness:
Histamine
Neurotransmitters which promote sleep:
GABA and adenosine
What wave pattern is indicative of REM sleep?
Theta waves
How long is a sleep cycle?
90 Minutes
Which phase of sleep do you normally wake from?
REM (Phase 1)
What is slow wave sleep?
Phase 3 and 4 sleep, characteristic of delta waves
Order the following three in terms of neural activity during the phases:
- REM
- Non-REM
- Waking
- REM
- Waking
- Non-REM
What is characteristic of REM sleep?
Dreams Theta waves Rapid eye movement Higher brain metabolism then waking Limbic system is activated (evolved in emotion) a part of it the amygdala helps to mediate anxiety and fear
What is characteristic of Non-REM sleep?
Lower metabolism
Slow wave sleep: delta in three and four phase
regular heart rate
Memory consolidation
Basal Nuclei/Ganglia:
- Gray or white matter:
- Predominant function:
- Most predominant structure:
Gray (a nuclei is composed of somas, which are not myelinated)
Motor function
Corpus striatum
Corpus Striatum:
- Is composed of several masses of nuclei named:
Caudate nucleus (upper mass) Putamen (Lower mass = lentiform nucleus) Globus Pallidus (Lower mass = lentiform nucleus) Latin for pale globe
Motor circuit:
1: Motor cortex sends excitatory impulses (glutamate is the neurotransmitter) to the basal ganglia (nuclei) predominantly the Putamen
2: The Putamen (and friends in basal nuclei) send inhibitory impulses to other basal nuclei (utilizing the neurotransmitter GABA)
3: The Globus pallidus and the substantia nigra send inhibitory axons to the thalamus (using our friend GABA yet again)
4: The thalamus sends excitatory neurons back to the motor cortex
What is the function of the motor circuit?
It allows intended movements to occur while inhibiting unintended movements
It sends inhibitory stimuli out of the basal ganglia to inhibit other regions.
The globulus pallidus is noteworthy for what action in the motor circuit?
extensive GABA based inhibitory action
the substantia nigra are related to Parkinson’s how?
The substantia negris sends dopaminergic neurons to the corpus striatum. Degeneration of these neurons results in parkinson’s disease.
Contralateral:
The opposite side of the body.
Decussation:
The action of nerve fibers crossing over each other
What causes epilepsy:
How do you treat epilepsy:
Uncontrolled electrical activity crossing from one side of the brain to the other.
Cutting the Corpus collusum (split brain procedure)
Cerebral laterization:
Refers to superior ability of one half of the brain to perform a task.
Where do the nerves crossover before they reach the brain?
The medulla oblongata (where both sensory and motor tracts cross)
Aphasia
A speech or language disorder
Broca’s Aphasia:
- Speech effect (why it is an aphasia):
- Motor effect:
Damage to the lower left side of the frontal cortex. Results in difficulty forming words but no difficulty understanding them. You can make sentences but words are hard to come up with and communication is slow.
It is on the left side so weakness will be seen on the right side of the face (contralateralism caused by decussation)
What does damage to wernicke’s area result in?
A loss of language comprehension. This area is found in the temporal lobe, which is associated with speech. You cannot make coherent sentences.
What would be the pathway for the interpretation of a communication based stimuli?
Temporal and occipital lobe will give information to Wernicke’s area. Wernicke’s area will integrate this information, and interpret it (written or spoken word). It will then send this information to Broca’s area, which decides how to respond (it does integrate with other areas), and sends this information to the motor cortex (precentral gyrus included) which sends those sweet words to your lips or lets your arm form those letters.
Limbic System:
- Function:
- Location:
- Nuclei included within:
- Function:
Emotion, sex, feeding, and goal driven behavior (it provides drivers which influence the rest of the brain), there is a satiety center which tells you - Location:
Around the brain stem in a circle - Nuclei included within:
Amygdala, Hippocampus (memory and emotion and drives), cingulate gyrus and septal nuclei
Longitudinal fisure:
Separates the two halves of the brain.
Alzheimer’s disease:
- Where is the affect localized:
- What is caused by the effect or the result of the effect (whether it is a cause or symptom is poorly understood)
- What is the protein which results in intracellular tangles
In the hippocampus (alzheimer’s and memory) and the cerebral cortex (other impairments, struggle in integration and general mental confusion)
Two types of plaques/tangles. One intracellular (a tangle) one extracellular (an amyloid beta plaque)
Abnormal protein Tau
Amygdala:
- How does the amygdala interrelate with memory and emotion
Amygdala results in an increased emotionally related ability to remember something
Stress can increase the ability to store memories but decrease the ability to recall these memories
Note:
Stress + emotions = Stronger memory + poor retrieval of memories (childhood abuse)
How can you help lower the chances that you will get alzheimer’s disease?
Eat antioxidant rich foods, exercise, puzzle solving
The hypothalamus is part of the limbic system, or at least integrates with it. What does it seem to do?
It seems to evaluate physiological needs (sex drive, hunger drive, ‘i’m thirsty’, etc.)
Of course these drives need to be attached to EMOTION (The lymbic system, amygdala, etc.)
Hypothalamus:
- Is feeding and satiety centers separate?
You bet your sweet booty. Stimulate the feeding center and you munch munch munch. Stimulate the satiety center and you don’t want to munch. Inhibit the satiety center and you likely want to munch. Could this be used to promote weight loss or gain?
What is the effect of stress on the hippocampus:
The hippocampus has cortisol receptors, and stress can literally cause it to waste away (atrophy).
There is also evidence of reduced neurogenesis from the stem cells here! (which reside in the subgranular zone?)
Orbitofrontal cortex:
- Local:
- Function:
- Connected to:
Note: this is a section of the of prefrontal cortex.
Note this complexes with everything in the prefrontal cortex.
- Local:
It is orbital (near the eye), and in the frontal cortex…
- Function:
Consciously experience pleasure and reward
- Connected to:
Cingulate gyrus, amygdala (may be connected to the nucleus accumbens)
What is the prefrontal cortex for?
It is involved in higher brain function. Memory planning, judgement, and interpersonal skills.
Lateral prefrontal/precentral cortex area:
Involved in cognitive function, motivation and sexual desire
Phineas Gage:
Damaged his prefrontal orbital area. Lost his ability to regulate social interactions. He was no longer socially inhibited, swore and cussed and was rather rude.
Diencephalon becomes:
Thalamus, epithalamus, hypothalamus, and the posterior pituitary gland
Which sense does not move through the thalamus:
What is the thalamus’s primary job?
The sense of smell is the only sense not processed on its way to the cerebral cortex by thalamus
Processing senses on the way to the cerebral cortex. it is the principle and final relay point to the cerebral cortex
Reticular activating system:
- Involves:
The thalamus is involved in promoting wakefulness (histamine). When your alarm goes off this helps you wake up (because auditory input relays through here)
Without the thalamus you will often enter a comma
Epithalamus:
- Dorsal region of the diencephalon
- Has a choroid plexus over the third ventricle
- Is where the pineal gland is located which is involved in melatonin (circadian rhythms)
Post traumatic stress disorder and memory:
PTSD can cause atrophy of the hippocampus
