Parts of the brain! Flashcards
The brainstem is where the spinal cord enters the ___
Skull
Do brainstem structures perform both sensory and motor funtions?
Yes
The region DORSAL to the fourth ventricle performs ____
Sensory functions
The region VENTRAL to the ventricle performs ___
Motor functions
Many cranial-nerve nuclei convege at the brainstem and send there axons to the muscles of the head.
Yes!
What does the brainstem consist of?
Cranial-nerve nuclei as well as many bundles of fibres from the spinal CORD that pass through the brainstem on their way to the brain. Same goes the other way (from the forebrain to brainstem to spinal cord).
Does the brainstem regulatemany complex functions?
Yep!!
The most distinctive part of the HINDBRAIN is the _____
Cerebellum!
What is the cerebellums function?
For fine, coordinated movements.
Where is the cerebellum located?
It protudes above the core of the brainstem
What does the cerebellum look like?
Its surface is gathered into small folds (folia)
What do the several nuclei do at the base of the cerebellum?
They send connections to other parts of the brain!
What happens if there is damage to the cerrebellum?
Equilibrium problems, postural defects and impairments in motor activity.
What is the role of the HINDBRAIN structures?
Integrating both voluntary and involuntary body movement and contributes to cycles of waking and sleeping
Within the core of the hindbrains mixture of nuclei and fibres lies a network referred to as the ____
Reticular formation
What is the function of the reticular formation?
To control sleeping and waking (to maintain general arousal or consciousness). Otherwise known as the reticular activating system.
What do structures in the midbrain do?
1) Mediate a wide range of visual and auditory-related behaviours.
2) Produce orienting movements, in species-specific behaviours.
3) The perception of pain.
What are the 2 main subdivisions of the Midbrain?
The tectum (dorally located) and the tegmentrum (ventrally located).
The tectum recieves a massive amount of sensory input from the ___ and ____
Eyes and ears
The superior colliculi recieves projections from the ___
Retina of the eye. (they also mediate many visually related behaviours).
The inferior colliculi receives projections from the ___
Ear. They mediate many auditory-related behaviours.
Another class of behaviours mediated by the colliculi is the orientation of movemens related to sensory input such as…
Turning your head to look at the source of sound
The ____ is composed of nuclei related to motor functions
Tegmentrum
The red nucleus controls___
Limb movements
The substantia niagra is connected to the ___brain
Forebrain
What is the role of the substantia niagra?
Important for reward and initiating movements
The periacqeuductal grey matter is made up of cell bodies that surround the acqueduct joining the ___ and ___ ventricles
Third and Fourth
What is the role of the periacqueductal grey matter?
Contains circuits for controlling species-typical behaviours for example sexual behaviour and for modulating responses to pain.
The Diencephalon is located in the ___
Brainstem
The Diencephalon consists of three thalamic structures:
1) Hypothalamus
2) Epithalamus
2) Thalamus
Does the Hypothalamus interact with the pituitary gland?
Yes!
What is the role of the hypothalamus?
Involved in nearly all aspects of motivated behaviour such as feeding, sexual behaviour, sleeping, temperature, emotional regulation, movement AND through its interacts with the pituitary gland- endocrine function (hormonal).
What is the largest structure in the Diencephalon?
The thalamus
How many nuceli does the thalamus have?
20 large nuclei, each which projects to a specific area of the cerebral cortex.
The group of 3 thalamic nuclei that relays information from sensory systems to their appropriate targets
1) Lateral geniculate body (LGB)
2) Medial geniculate body (MGB)
3) Ventrolateral posterior nuclei (VPN)
The LGB recieves…
Visual projections
The MGB recieives…
Auditory projections
The VLP recieves…
Touch, pressure, pain and temperature projections from the body.
The 3 thalamic nuclei areas project to the ___,____ and ___ regions of the cortex
Visual, auditory & somatosensory regions
Some thalamic nuclei relay information from other forebrain and brainstem regions
YES
Some thalamic nuclei relay information BETWEEN cortical areas
Yes, recieive info to and from.
All of the information recieived by the cortex is first relayed through the ___
Thalamus
The forebrain consists of 3 regions..
1) Basal Ganglia
2) Limbic system
3) Neocortex
What is the main role of the basal ganglia ?
Motor coordination
What is the main role of the limbic system?
Emotion and memory
What is the main role of the neocortex?
Sensory, motor and cognitive functions.
What 3 structures make up the basal ganglia?
Globus pallidus, putamen and caudate nucleus
The ganglia have functions related to movement and to___
Simple forms of learning
Where is the basal ganglia located?
They are a collection of nuceli lying mainly underneath the anterior regions of the cortex
Do the basal ganglia also have connections to the midbrain?
Yes! They have reciprocol connections with the substantia niagra in the mid brain tegmentum.
What changes may occur if the Basal Ganglia is damaged?
Damage to different parts of the Basal Gangliacan produce changes in posture, increases or decreases in muscle tone and abnormal movement such as jerks, twitches or tremors.
What 3 dieases of the basal ganglia illustrate its motor functions?
1- Huntingtons diesease:
2- Parkinsons diesease:
3- Tourettes syndrome:
What is Huntingtons diesease?
A genetic disorder where cells of the B.G die progressively and associated with this cell death, many involuntary movemens of the body occur almost continuously.
What is Parkinsons diesease?
Where the projections from the susbtantia niagra to the basal ganglia die. Associated with this cell death the patient becomes rigid and has difficulty moving and maintaining balance. The patient may also display rhythmical tremors of the hands and legs.
What is Tourettes?
Another disorder of the BG, the most common symptom is involuntary motor tics- esp of the face and head and complex movements such as hitting, lunging or jumping. Also involuntary vocalisations.
The 3 disorders of the BG are disorders of ____ movements
CONTROLLING
The basal ganglia plays a huge role in the ___ and ____ of movement patterns, NOT in activiating the muscles
Control AND coordination
Control and coordination of motor movements is 1 function of the BG. What is its second function??
To support stimulus-response (aka HABIT LEARNING).
The basal ganglia are critical in learning the ASSOCIATION between taste and colour.
YES
Many or our ___ are responses to sensory cues
Actions (habit based learning which involves the BG).
The Limbic lobe (limbic system) consists of a number of interrelated structures. What are they called?
Amydala
Hippocampis
Septum
Cingulate cortex
The nuceli that form the Amygdala and septum plays roles in ______ and ____ behaviours.
Emotional and species-specific behaviours
What is the role of the Hippocampus?
Memory and spatial navigation
The limbic lobe terminates in the ____
Amygdala
The hippocampus contains many receptors for the stress hormone_____
Corticosterone
The limbic structuress play roles in emotional and sexual behaviours but ALSO serve other functions in….
Memory, motivation, reward and navigation
What is the primary function of the Neocortex?
To create and respond to perceptions of the world
Is the Neocrotex heavily folded?
Yes! It is folded to allow the human brain to fit comfortably within the fixed volume of the skull.
What are the names of the 4 lobes of the brain?
Frontal lobe, parietal lobe, temporal lobe and occipital lobe.
The most obvious surface feature of the Neocortex is its crinkled tissue which consists of …
Clefts and ridges
A cleft is called a ____ if its extends deeply enough into the brain to indent the ventricles.
Fissure
If the fold is shallower then it is called a cleft or
Sulcus
A ridge is called a…
Gyrus or ‘Gyri’
The cingulate gyrus spans ALL FOUR neocortical lobes
True!
Ridges are ____
GYRI
Clefts are ____
SULCI
Different regions of the cortex have different functions
True
Inputs to the cortex are relayed through the ____
Thalamic nuclei
Different regions of the Neocortex have different functions. For example…
Some regions recieve information from sensory systems, others command movements and others are the sites of the connections between sensory and motor areas.
The Neocortex consists of a number of fields:
Visual, auditory, body senses & motor.
Vision, audtion and body senses are functions of the ____ cortex
Posterior
Parietal, temporal and occipatal lobes are considered largely as…
Sensory.
Motor function is located in the ____cortex
Frontal
Frontal lobes…
Motor function
Parietal lobes…
Body senses
Temporal lobes…
Auditory function
Occipital lobes…
Visual function
The association between a particular lobe of the brain with a particular function is rough but relates to that area of the brain being a ____projection area
Primary
What projection area recieve sensory input or project to spinal motor systems?
Primary projection areas
What projection area interpret sensory input or organise movement?
Secondary projection areas
What projection area modulate information between secondary areas?
Association areas
Does information flow from primary to secondary areas?
YES! And also from secondary areas to primary areas.
Sensory projections from the EYE can be traced to the ___
Occipital lobe
Sensory projections from the EAR can be traced to the ____
Temporal lobe
Sensory projections from the SOMATOSENSORY system can be traced to the ____
Parietal lobe
The OLFACTORY system sends projections to the ___
Ventral and frontal lobe.
The secondary areas are LESS directly connected with the sensory receptors and motor neurons
True. The primary areas are. The secondary areas are more engaged with INTERPRETING sensory input or ORGANISING movements than are primary areas.
Tertiary areas are all of the areas of the cortex that are NOT specialised for sensory or motor function.
True. This area instead MEDIATES complex activities such as language, planning, memory and attention.
The neurons of the neocortex are arranged in ___ layers
6
Are there connections between various regions of the cortex?
Yes!
What connects one lobe of the brain to another and one part of the lobe to another part, and even one hemisphere of the brain to the other?
Axon fibres
Damage to an area of the cortex almost certainly involes damaging 1 or more of its interconnecting pathways.
True.
The various neocortical regions are interconnected by ___ types of axon projections. What are they?
Four.
1) Long connections between one lobe and another
2) Relatively short connections between one part of the lobe and another
3) Interhemisphereic connections betwen 1 hemisphere and the other
4) Connections through the thalamus
What does it mean by the ‘crossed brain?’
That each of the brains symetrical halvess responds mainly to sensory stimulation from the CONTRALATERAL side of the body or sensory world and controls the muscles on the CONTRALATERAL side of the body.
