Chapter 1 Flashcards
Describe different anatomical brain structures and structures in the CNS, and identify their roles.
What is the goal of both cognitive neuroscience and neuropsychology?
To understand the relationship between brain and behaviour/cognition
What does cognitive neuroscience focus on?
It relies primarily on neuroimaging techniques in normal individuals
What is the difference between neurological and psychological approaches to neuropsychology?
Neurological approaches things from an anatomical perspective; it looks at brain structures and connections, which we can then use to infer specific functions
Psychological approaches things from a psychological perspective; it looks at psychological phenomena like memory, then asks which brain areas are responsible for completing this task
What does experimental neuropsychology focus on?
It relies on findings from individuals with brain damage
What is the function of clinical neuropsychology?
To assess, diagnose, and treat cognitive deficits
When we look at people like Albert Einstein, how can we explain the differences in brain structure compared to normal individuals?
There were a greater number of sulci and gyri on the surface of Einstein’s brain; from this we can deduce that sulci and gyri can potentially explain greater mental capabilites
What two structures are included in the central nervous system (CNS)?
the brain and spinal cord
What is the function of astroglia?
They provide structural support to the neurons and work in repairing them
What is the function of oligodendroglia?
They insulate and provide speed in transmission in CNS
What is the function of Schwann cells?
They insulate and provide speed in transmission in the PNS
What is the function of microglia?
they are phagocytes; they ingest potentially harmful organisms
What is the function of ependymal cells?
They line the ventricles and produce cerebral spinal fluid (CSF)
What is another very important role of glial cells?
They are essential in maintaining the blood-brain barrier
Describe the directionality of the brain. Use all the appropriate terms.
- rostral = towards the head
- caudal = towards the tail
- superior = top half of brain
- inferior = bottom half of brain
- dorsal = towards the back
- ventral = towards the stomach
- middle brain = medial (close to the midline)
- towards the outside of the brain = lateral (far from the midline)
Describe each of the ways we can slice the brain
- coronal = ear to ear
- horizontal = top half from bottom half
- sagittal = when the left is separated from the right
What are nuclei? Where are they found?
Nuclei are distinct groups of neurons whose cell bodies are located in the same region; they are located in the thalamus
Are motor movements controlled ipsilaterally or contralaterally?
They are controlled contralaterally
In addition to protecting the brain and spinal cord from pathogens, what does CSF also help with?
CSF also serves to supply the metabolic needs of the brain and spinal cord; just like blood does in the PNS
Why would it be more difficult to treat infections found inside the CNS as opposed to the PNS?
Because white blood cells and phagocytes cannot cross the blood-brain barrier, so treatment becomes a bit more complicated (a medication that could cross this barrier would be needed).
What is the primary function of the spinal cord?
The spinal cord receives and transmits most information in the body
What are the ventricles?
CSF filled cavities in the brain
Why is the medulla so important?
1) it is the region of the brain that contains many of the cell bodies of the 12 cranial nerves
2) it is at the medulla that most motor fibres cross contralaterally at the decussation of the pyramids
3) the medulla also contains many vital reflexes such as respiration and heart rate
4) the medulla houses the reticular activating system
What is the function of the reticular activating system?
It is important for overall attention and arousal, and for regulating sleep-wake cycles
What is the cerebellum important for? Where does it receive input from?
In regulating muscle tone and guidance of motor activity (this area of the brain gets affected with alcohol)
- the cerebellum receives input from (1) the spinal cord (proprioception), (2) vestibular nucleus (balance) and (3) the cortex (the cerebellum receives commands from the cortex to voluntarily move)
What is the primary function of the lateral cerebellum?
it is involved in motor control and learning motor skills, certain aspects of cognitive functioning and for timing information
What is the function of the pons?
This brain structure contains the point of synapse for some cranial nerves, and acts as the control centre for certain kinds of eye movements; it also helps with balance and contains the superior olive
- the pons is also the bridge between the cerebellum and the rest of the brain
What is the function of the superior olive?
This area is where auditory information from both ears converge
- this allows for comparison of information from each ear
What is the inferior colliculus responsible for? Where is this located?
The inferior colliculus is responsible for orienting to stimuli in the auditory modality, sound localization and contributes to reflexive movement of the eyes and head in response to a sound
- it is located in the tectum in the midbrain
What is the superior colliculus responsible for? Where is it located?
The superior colliculus is responsible for orienting to stimuli in the visual modality (perceiving stimuli in the periphery and orienting ourselves towards it)
- it is located in the tectum in the midbrain
What does the midbrain contain?
the nuclei of the cells that form some cranial nerves
What is foveation?
guiding an object towards the centre of the visual field
What is the hypothalamus responsible for?
It controls behaviours that regulate homeostasis (ex. eating, drinking, sleeping, temperature)
What does diurnal mean?
Daily
What does damage to the ventromedial hypothalamus lead to?
Excessive eating, causing weight gain
What does dorsal and lateral damage to the hypothalamus lead to?
Interference of water intake
What do the anterior and posterior hypothalamus detect?
Changes in temperature
What does the hypothalamus have a direct relationship to?
the pituitary gland (and therefore, it has a relationship to the hormonal system)
What does the suprachiasmatic nucleus responsible for?
It controls the fluctuations of hormonal release throughout the day due to receiving input from the retina
What is a relay center?
A brain region in which the neurons from one brain area synapse to neurons that go to synapse in other areas of the brain
- the point of a relay center is to reorganize information going in and out of the brain
Where does the information from the optic tract synapse to?
The lateral geniculate nucleus (the LGN)
- the magnocellular layer receives low light info
- the parvocellular layer receives colour info
What are subcortical systems?
Structures and systems located below the cerebral cortex
What is the lateral hypothalamus important for?
Activating the fight or flight response
What is the responsibility of the thalamus?
It is the relay centre for almost all sensory info coming into the cortex, and almost all motor info leaving the cortex
What three structures can be found in the basal ganglia?
- the caudate nucleus
- the putamen
- the globus pallidus
What is the basal ganglia important for?
motor control (damage leads to involuntary movement)
What is the role of the limbic system?
it integrates emotional information between various parts of the nervous system
ex. seeing a threatening animal, we must integrate
(1) information about fear from the hypothalamus
(2) information about identifying the animal from the visual cortex, and
(3) information from other regions about memories of encounters with animals of that size
What is a gyrus?
it is the bumps of the brain, they are a giant sheath of neurons wrapped around other brain structures
What is a sulcus?
A valley between the bumps
Whats is a fissure?
A deep sulcus
How many fissures are there? How do they serve as landmarks of the brain?
there are three fissures:
(1) the central fissure - separates each hemisphere in the anterior - posterior dimension
(2) the sylvian fissure - separates each hemisphere in the dorsal - ventral dimension
(3) the longitudinal fissure - separates the right hemisphere from the left
What does the amygdala serve to do?
It controls the fear response and is thought to play an important role in emotional functioning
What is the role of the hippocampus?
The hippocampus plays an important role in memory (such as the formation of new long-term memories)
What does the cingulate cortex control?
Motor function in relation to selection of actions
What does the cerebral cortex control?
Object recognition, spatial recognition and attention
What role is carried out in front of the central fissure?
motor processing
What role is carried out behind the central fissure?
sensory processing
What is cytoarchitectonics?
The pattern of cellular organization
What is grey matter mostly made up of?
Neural cell bodies
What is white matter mostly made up of?
Axons (this is white due to the myelin of the axons)
Give one example of how microscopic neural changes can lead to large scale outcomes?
Alzheimer’s disease changes the structure of the neuron
Why do motor neurons tend to be longer than other kinds of neurons?
Because the information they carry has to be transmitted over a larger area (distally)
- the morphology of a neuron describes its function
What is the only sense that is processed ipsilaterally?
Olfaction
What are the 4 major subdivisions of the spinal cord?
- cervical
- thoracic
- lumbar
- sacral
What is a fibre pathway/tract/fasciulus?
A large collection of axons (bundles of white matter)
What is reticular matter?
Grey and white matter intermingled
What is the insula important for?
Taste
What is the somatic NS responsible for?
Sensory and motor functioning
What is the autonomic NS responsible for?
This NS controls the body’s internal environment (organs and automatic things like breathing and heart rate)
How many pairs of spinal nerves are there?
31 pairs; each pair corresponds with a region in the body which is affected by the nerve (when there is damage, the deficit tells us where the damage is)
What does the autonomic NS consist of? What is the function of each? Where are they located on the spinal cord?
- the sympathetic NS - specialized in activity (fight vs. flight response) - localized in the thoracic and lumbar regions
- the parasympathetic NS - specialized in inactivity (rest & digest) - localized in the sacral region
What is the postcentral gyrus responsible for?
This is the primary somatosensory cortex (in front of the central sulcus)
What is the precentral gyrus responsible for?
This is the primary motor cortex (behind the central sulcus)
What are ventral nerves responsible for?
These are motor nerves (they are efferent)
What are dorsal nerves responsible for?
These are sensory nerves (they are afferent)
Describe the Bell-Megendie law?
Dorsal nerves are sensory and ventral nerves are motor
Why does sensorimotor reflect happen directly at the spinal cord?
This allows us to react quickly to potentially harmful stimuli
What is something we can measure at the spinal cord?
Emotional responses
- activates action preparedness in response to negative images
What does the tectum help us to do?
Orient ourselves to sound and visual information
- contains the superior and inferior colliculi
What does the tegmentum contain?
Various dopaminergic nuclei and cranial nerves
What kinds of information do the cranial nerves receive?
sensory and motor info (like the spinal cord, except at the level of the head)
- most are part of the somatic PNS (ex. the facial nerve)
- some are part of the CNS (the 5 sensory nerves)
How many cranial nerves are there? Name the cranial nerves related to the 5 special senses:
there are 12 in total
- olfactory (smell)
- optic (vision)
- trigeminal (sensations from skin of face, nose and mouth)
- facial (taste from front 2/3 of tongue and sensations from the head)
- statoacoustic (hearing and equilibrium)
- glossopharyngeal (taste from back 1/3 of tongue and other throat sensations)
- vagus (taste, sensations from neck, thorax and abdomen)
What are the cranial nerves associated with the 5 special senses? What do they do, what is their motor component?
Cranial Nerve I :Olfaction (smell), no motor component
Cranial Nerve II :Optic (vision), no motor component
Cranial Nerve VIII :Statoacoustic (hearing & equilibrium), no motor component
Cranial Nerve VII :Facial nerve (taste from front 2/3 of tongue and sensations from the head), involved in facial expression, crying, salivating, dilation of blood vessels in the head
Cranial Nerve IX :Glossopharyngeal (taste from back 1/3 of tongue, and other throat sensations), involved in swallowing, salivation, dilation of blood vessels in the head
Cranial Nerve X :Vagus Nerve (taste and sensations from the neck, thorax and abdomen), involved in swallowing, control of larynx; parasympathetic nerves to heart and viscera
