Week 4 Flashcards
What is the central nervous system?
Brain and spinal cord
What is the peripheral nervous system?
Connect the brain and spinal cord to the rest of the body
What is the somatic nervous system?
Axons conveying messages from the sense organs to the central nervous system and from the CNS to the muscles.
What is the autonomic nervous system?
Where are its cell bodies?
Control the heart, intestines, and other organs.
Has some cell bodies within the brain or spinal cord and some in clusters along the sides of the spinal cord.
What is dorsal?
Towards the back
What is ventral?
Toward the stomach
What is anterior?
Toward the front end
What is posterior?
Towards the rear end
What is superior?
Above another part
What is inferior?
Below another part
What is lateral?
Toward the side, away from the midline
What is proximal?
Located close (approximate) to the point of origin or attachment
What is distal?
Located more distant from the point of original or attachment
What is ipsilateral?
On the same side of the body
E.g. Two parts on the left or two on the right
What is contralateral?
On the opposite side of the body
E.g. One on the left, one on the right
What is the coronal / frontal plane?
A plane that shows brain structures as seen from the front
What is the sagittal plane?
A plane that shows brain structures as seen form the side
What ist he horizontal / transverse plane?
A plane that shows brain structures as seen from above
What is a lamina?
Row or layer of cell bodies separated from other cell bodies by a layer of axons and dendrites
What is a column?
Set of cells perpendicular to the surface of the cortex, with similar properties
What is a tract?
Set of axons within the CNS, also known as a project. If axons extend from cell bodies in structure A to synapses onto B, we say that the fibres “project” from A onto B.
What is a nerve?
A set of axons in the periphery, either from the CNS to a muscle or gland or from a sensory organ to the CNS
What is a nucleus?
A cluster of neuron cell bodies within the CNS
What is a ganglion?
A cluster of neuron cell bodies, usually outside the CNS (as in the sympathetic nervous system)
What is a gyrus?
A protuberance on the surface of the brain
What is the sulcus?
A fold or groove that separates one gyrus form another
What is a fissure?
A long, deep sulcus
What term means “towards the midline” and what term means its opposite?
Medial
Lateral
Which sense organs and muscles does the spinal cord communicate with?
All except those of the head
What do the entering dorsal roots (axon bundles) do?
Carry sensory information
What do the exiting ventral roots do?
Carry motor information
What are the cell bodies of sensory neurons, which are in clusters of neurons outside the spinal cord, called?
Dorsal root ganglia
What are the two parts of the autonomic nervous system?
Sympathetic and parasympathetic nervous systems
What is the sympathetic nervous system?
What are some of its functions?
A network of nerves that prepare the organs for a burst of vigorous activity.
Consists of chains of ganglia just to the left and right of the spinal cord’s central regions (the thoracic and lumbar regions).
Prepares the organs for fight or flight, such as by increasing breathing and heart rate, and decreasing digestive activity.
What kinds of things have sympathetic input, but not parasympathetic input?
Sweat glands
Adrenal glands
Muscles that constrict blood vessels
Muscles that erect hairs of the skin.
What is the parasympathetic nervous system?
What are some of its functions?
“Rest and digest” system
Facilitates vegetative, nonemergency responses.
Often performs the inverse of the sympathetic nervous system; decreases heart rate, increases digestive activity.
Promotes sexual arousal, including erection in males.
How are parasympathetic ganglia arranged?
Preganglionic axons extend from the spinal cord to parasympathetic ganglia close to each internal organ.
Shorter postglangionic fibres then extend from the parasympathetic ganglia into the organs themselves.
What neurotransmitter does the PNS’s axons release into the organs?
Acetylcholine
What neurotransmitters do the SNS’s axons release?
Norepinephrine, although some like the sweat glands use acetylcholine
How do drugs affect the PNS and SNS?
Different drugs excite or inhibit one system or the other.
E.g. Cold remedies exert most of their effects by blocking parasympathetic activity or increasing sympathetic activity.
Some cold remedies block sinus flow. What effect on the PNS or SNS is this displaying?
Suppressing the PNS
Motor nerves leave from which side of the spinal cord, dorsal or ventral?
Ventral
What are the three major divisions of the brain?
Hindbrain
Midbrain
Forebrain
Where is the hindbrain?
What are its three components?
Posterior part of the brain
Medulla
Pons
Cerebellum
Which parts of the brain constitute the brainsteam?
Hint: This is quite broad
Medulla and pons
Midbrain
Certain central structure of the forebrain
What is the medulla?
Enlarged extension of the spinal cord.
Just as the lower parts of the body connect to the spinal cord via sensory and motor nerves, the head and the organs connect to the medulla and adjacent areas.
What vital reflexes does the medulla control?
Breathing Heart rate Vomiting Salivation Coughing Sneezing
How do opiates affect the medulla?
Opiate receptors are abundant in the medulla and can produce a dangerous decrease in breathing and heart rate.
What and where is the pons?
HINT: Think about the Latin meaning of pons
Means “bridge” in Latin
Axons from each half of the brain cross to the opposite side of the spinal cord so that the left hemisphere controls the muscles of the right side of the body and vice versa.
Anterior and ventral to the medulla.
What and where is the cerebellum?
Large hindbrain structure with many deep folds.
Contributes to the control of movement, balance, shifting attention between auditory and visual stimuli, timing (such as judging difference in speed of rhythm).
What is the roof of the midbrain called?
The tectum
What are the swelling on each side of the tectum?
Superior colliculus
Inferior colliculus
What lies under the tectum?
Tegmentum
What are the substantia nigra?
Midbrain structure that gives rise to a dopamine-containing structure that facilitates readiness of movement.
Which cranial nerves control taste, control of tongue and throat movements?
Facial
Glosspharyngeal
Hypoglossal
Which cranial nerves control eye movement?
Oculomotor
Trochlear
Adbucens
What is the forebrain?
Most prominent part of the mammalian brain, consisting of two cerebral hemipheres.
How do the hemispheres of the forebrain receive information?
Contralaterally; from the opposite side of the body.
What is the outer portion of the forebrain?
Cerebral cortex Latin cerebrum (brain) cortex (shell)
What structure form the limbic system?
Olfactory bulb Hypothalamus Hippocampus Amygdala Cingulate gyrus
What does the hypothalamus control?
Eating
Drinking
Temperate control
Reproductive behaviour
What is the amydala for?
Emotion, especially fear
What is the thalamus?
Pair of structure in the centre of the forebrain.
Derived from Greek word meaning anteroom / inner chamber / bridal bed.
Most sensory information goes first to the thalamus, which processes it and sends output to the cerebral cortex EXCEPT olfactory information, which goes to the olfactory bulbs and then directly to the cerbral cortex.
What is the hypothalamus?
Has widespread connections to the rest of the brain.
Conveys messages to the pituitary gland through nerves and by releasing hormones.
What results from damage to hypothalamic nuclei?
Abnormalities in motivated behaviours such as: Feeding Drinking Temperature regulation Sexual behaviour Fighting Activity level
What is the pituitary gland?
An endocrine (hormone producing) gland attached to the base of the hypothalamus. Synthesizes hormones carried by the blood to organs throughout the body.
What are the three major structures of the basal ganglia?
Caudate nucleus
Putamen
Globus pallidus
What results from damage to the basal ganglia?
Impaire movement, such as in Parkinson’s and Huntington’s.
Beyond movement, what are the basal ganglia for?
Learned skills and habits
Types of learning that develop gradually with extended experience.
What is the nucleus basalis?
On the ventral surface of the forebrain. Receive input from the hypothalamus and basal ganglia and sends axons that release acetylcholine to widespread areas in the cerebral cortex. Important for: Arousal Wakefulness Attention
How do Parkinson’s and Alzheimer’s affect the nucleus basalis?
Impairments of attention and intellect
What is the hippocampus?
Derived from Latin “seahorse” due to shape.
Located at posterior of forebrain.
Critical for:
Certain types of memories, especially memories for individual events
Navigation
Which area is the main source of input to the cerebral cortex?
Thalamus
What are the ventricles?
Four fluid filled cavities in the brain.
Cells called choroid plexus along the walls of the ventricles produce cerebrospinal fluid.
What does cerebrospinal fluid do?
Cushions the brain against mechanical shock.
Provides boyancy to support the weight of the brain.
Provides a reservoir of hormones and nutrition for the brain and spinal cord.
What are the meninges?
Membranes surrounding the brain and spinal cord
What illnesses are the meninges related to?
Meningitis - inflammation of the meninges (membranes surrounding the brain and spinal cord)
Migraine - swollen blood vessels in the meninges
1. What does ventral mean? A. Toward the side B. Toward the front C. Toward the stomach D. Toward the head
C. Toward the stomach
2. If two structures are both on the left side, or both on the right, what is their relationship? A. Medial B. Ventral C. Ipsilateral D. Contralateral
C. Ipsilateral
- What is a sulcus in the brain?
A. A groove that separates one gyrus from another
B. A fluid-filled cavity
C. A set of axons from one brain structure to another
D. A temporary decrease in activity
A. A groove that separates one gyrus from another
- What is the function of the dorsal roots of the spinal cord?
A. They receive sensory input.
B. They control motor output.
C. They convey information from the brain to the spinal cord.
D. They convey information from the spinal cord to the brain.
A. They receive sensory input.
5. What does the parasympathetic nervous system control? A. Fight-or-flight activities B. Vegetative activities C. Social behavior D. Learned habits
B. Vegetative activities
6. Which of these controls breathing, heart rate, and salivation? A. The hippocampus B. The cranial nerves C. The basal ganglia D. The pituitary gland
B. The cranial nerves
7. Which of these is part of the forebrain? A. Hippocampus B. Medulla C. Pons D. Cerebellum
A. Hippocampus
8. Which structure provides most of the direct input to the cerebral cortex? A. Cranial nerves B. Medulla C. Thalamus D. Pineal gland
C. Thalamus
9. What do the ventricles contain? A. Densely packed neuron cell bodies B. Glia C. Cerebrospinal fluid D. Long axons
C. Cerebrospinal fluid
How does the size and composition of the human brain compare to other mammals?
Proportionally larger cerebral cortex, more folding, more neurons per unit of volume.
Cerebellum is largely consistent across species (10-14% of the brain).
What are the laminae?
Six distinct layers of cell bodies, parallel to the surface of the cortex.
Vary in thickness and prominence from one part of the cortex to another, and may be absent from certain areas.
Refer to P. 83 for more info.
How are the cells of the cortex organised?
In “columns” of similarly functioned cells.
E.g. If one cell in a column responds to a horizontal pattern of light in a particular location, then other cells in the column respond to the same pattern in nearby locations.
Where and what is the occipital lobe?
Posterior (caudal) end of the cortex
Main target for visual information
What is the posterior pole of the occipital lobe known as?
Primary visual cortex
What happens when the occipital lobe is damaged?
Blindness
The eyes are responsible for the stimuli, the visual cortex is responsible for the experience
Where is the parietal lobe?
What does it do?
Between the occipital lobe and the central sulcus, a deep groove in the surface of the cortex.
Monitors information about:
Position of eyes, head, and body
Numerical information
What is the postcentral gyrus?
Receives sensations from touch receptors, muscle stretch receptors, and joint receptors.
What is the temporal lobe?
Lateral portion of each hemisphere, near the temples.
Primary cortical target for auditory information.
Contributes to complex aspects of vision, including perception of movement and recognition of faces.
Emotional and motivational behaviours.
What might result from a tumour on the temporal lobe?
Auditory or visual hallucinations
What syndrome may result from damage to the temporal lobe?
Kluver-Bucy syndrom
Causes individuals to put things in their mouths and engage in inappropriate sexual behaviour.
What might result from a tumour on the occipital lobe?
Simple sensations such as flashes of light.
What two cortices comprise the frontal lobe?
Primary motor cortex
Prefrontal cortex
What is the precentral gyrus?
Specialised for control of fine movements, such as moving a finger.
What is the most anterior portion of the front lobe?
Prefrontal cortex
How is the prefrontal cortex of humans and other primates different to other mammals?
Forms a larger portion of the cortex in humans and primates.
Has a huge number of synapses and integrate and enormous amount of information.
Which love of the cerebral cortex includes the primary auditory cortex?
Temporal lobe
Which lobe of the cerebral cortex includes the primary somatosensory cortex?
Parietal lobe
Which lobe of the cerebral cortex includes the primary visual cortex?
Occipital lobe
Which lobe of the cerebral cortex includes the primary motor cortex?
Frontal lobe
Who conducted many of the lobotomies of the 40s and 50s.
Walter Freeman
What are some of the common consequences of lobotomies?
Apathy Inability to plan or take initiative Memory disorders Distractibility Loss of emotional expressions Loss of social inhibitions
What are the three major regions of the frontal cortex and their functions?
Posterior:
Movement
Middle zone:
Memory
Cognitive control
Emotional reactions
Anterior zone:
Making decisions
Evaluating which of several courses of action is likely to achieve the best outcome
How valuable a reward may be to you in context (E.g. A pizza may be less valuable if you have just eaten)
What area of the brain may be damaged if someone has an issue with a delayed-response task, in which they see or hear something, and then have to respond to it after a delay?
Pre-frontal cortex
What is the binding problem?
Also known as the large scale integration problem
The question of how various brain areas produce a perception of a single object
When does binding occur?
When you perceive two sensations happening at the same time and in the same place
E.g. When a ventriloquist say somethings and makes the dummy’s mouth move at the same time, you perceive the sounds as coming from the dummy. As part of this illusion, the visual stimulus alters the response of the autidory cortex.
See pp. 87-88
- What is the main way in which mammalian species vary in their cerebral cortex?
A. The locations of visual and auditory cortex vary among species.
B. Some mammals have a cerebral cortex and some do not.
C. Brains differ in their size and degree of folding.
D. The number of laminae varies from 2 to 12.
C. Brains differ in their size and degree of folding.
- In which of these ways do primates differ from elephants in their cerebral cortex?
A. Primates have more neurons per unit volume.
B. Primates have a larger volume of cerebral cortex.
C. The average size of neurons is greater in primates.
D. The average length of axons is greater in primates.
A. Primates have more neurons per unit volume.
- What is the relationship between columns and laminae in the cerebral cortex?
A. Each column contains one and only one lamina.
B. Each column crosses through one lamina after another.
C. Some parts of the cortex have columns and others have laminae.
D. A column is just another word for a lamina.
B. Each column crosses through one lamina after another.
4. Where is the primary visual cortex? A. Temporal lobe B. Frontal lobe C. Parietal lobe D. Occipital lobe
D. Occipital lobe
5. Where is the primary somatosensory visual cortex? A. Temporal lobe B. Frontal lobe C. Parietal lobe D. Occipital lobe
C. Parietal lobe
6. Where is the primary auditory cortex? A. Temporal lobe B. Frontal lobe C. Parietal lobe D. Occipital lobe
A. Temporal lobe
7. Where is the primary motor cortex? A. Temporal lobe B. Frontal lobe C. Parietal lobe D. Occipital lobe
B. Frontal lobe
- The main functions of the prefrontal cortex include which of the following?
A. Perceiving the location of body parts in space
B. Providing a pool of immature neurons to replace those damaged in other brain areas
C. Controlling reflexes
D. Working memory and weighing the pros and cons of a possible action
D. Working memory and weighing the pros and cons of a possible action
- What is the binding problem?
A. The difficulty of coordinating the left side of the body with the right side
B. The difficulty of synchronizing output from a population of axons
C. The question of how we perceive separate sensations as part of a single object
D. The question of how a bilingual person shifts from one language to another
C. The question of how we perceive separate sensations as part of a single object
