The Brain Flashcards
What is a tract ?
A fibre pathway passing through the CNS carrying a specific modality.
What is the function of the brainstem ?
- Its a pathway for fibre tracts between higher and lower centres
- Involved in controlling basic body functions such as breathing and heart rate
What reflex is the superior colliculi involved with ?
Visual reflex
What reflex is the inferior colliculi involved with ?
Auditory reflex
Which fissure separates the temporal and frontal/parietal lobes ?
Lateral fissure
Which sulcus separates the frontal and parietal lobes ?
Central sulcus
Which sulcus separates the occipital and parietal lobes ?
Parieto-occipital sulcus
Where does the cerebellum get information from ?
- Vestibular nuclei
- Proprioceptors in limbs
- Cerebrum
What makes up the Diencephalon ?
- Thalamus
- Hypothalamus
- Pineal gland
- Pituitary gland
What is the main function of the Thalamus ?
It is a sensory relay centre
What structure separates the Thalamus and Hypothalamus ?
The hypothalamic sulcus
What is the basal ganglia ?
Collection of neuronal cell bodies buried in the white matter of the brain
What is hemispatial neglect ?
A deficit in attention and awareness to one side of the field of vision. Cause by damage to one hemisphere of the brain.
What causes right-left agnosia (confusion) ?
A lesion to the dominant parietal lobe
What is Aphasia ?
It affects the production or comprehension of speech and the ability to read or write.
What happens when a person has Broca’s Aphasia ?
They are able to understand speech but cannot or struggle to speak.
What happens when a person has Wernicke’s Aphasia ?
The can’t speak but struggle to understand what someone else says. They may not make sense.
What do commisural fibres connect ?
They connect corresponding areas of the two hemispheres e.g. the Corpus Callosum
What do association fibres connect ?
Different areas of the same hemisphere
What do projection fibres connect ?
The cortex and subcortical regions
What makes up the basal ganglia ?
- Caudate Nucleus
- Putamen
- Globus Pallidus
- Substantia Nigra
What are the input regions of the basal ganglia ?
The Caudate Nucleus and the Putamen
What are the output regions of the basal ganglia ?
The Globus Pallidus and Substantia Nigra
Where does the Globus Pallidus project to ?
Thalamus
What is the role of the Basal Ganglia ?
To help initiate and regulate movement
Definition of Cognition
The integration of sensory information to make sense of a situation
What role does the hippocampus have in memory ?
Memory formation
What role does the amygdala have in memory ?
Puts an emotive feeling on a memory
What role does the thalamus have in memory ?
It finds the memory
What role does the cortex have in memory ?
It stores the memory
What makes up the limbic system ?
Amygdala
Hypothalamus
Cingulate gyrus
Hippocampus
What determines the significance of an event ?
Frontal cortex and the limbic system
What is sensory memory ?
Memory of what happened seconds ago e.g. visual memory (< 1s) and auditory memory (< 4s).
What is short-term memory ?
Compromises daily tasks, your working memory. Last seconds to hours.
What is you immediate long-term memory ?
What you did last weekend, hours to weeks ago. its associated with changes in the chemical activity within synapses.
What is your long term memory ?
Where you lived as a child, who your friends were. Associated with structural changes in synapses.
What is short term memory dependent on ?
Reverberating circuits
What happens when a short term memory is deemed significant ?
Leaves the reverberating circuit and is stored in long-term memory.
Definition of Amnesia
Memory loss
What is Anterograde Amnesia ?
Can’t form new memories
What is Retrograde Amnesia ?
Can’t remember newer old memories
What is explicit long-term memory ?
Abstract memory from events. It involves the hippocampus.
What is procedural long-term memory ?
Through repetition its acquired slowly. Doesn’t involve the hippocampus, it is mainly based in the cerebellum.
What is the name of the circuit that occurs in the limbic system ?
Papez circuit
Describe the Papez circuit
Cortex - Thalamus - Cingulate gyrus - Hippocampus - Mamillary body - Cortex or Thalamus
Which neurones are needed for REM sleep ?
Cholinergic
What do people with Alzheimers not have a lot of ?
REM sleep - little memory consolidation occurs