Basal ganglia and limbic system Flashcards
function of the limbic system
learning
memory
emotion
structures involved in the limbic system
parahippocampal gyrus hippocampus fornix mamillary body Hypothalamus cingulate gyrus Amygdala
structures within the basal ganglia
substantia nigra Caudate nucleus putamen internal, external globus pallidus Subthalamic nucleus
role of the medial medullary lamina
a section of white matter that splits the medial and lateral globus pallidus
what does the olfactory tract split into and what are the functions
splits into olfactory striae lateral and medial
lateral fibres to the hippocampus - for memory
medial to the thalamus for smell
what structure is superior to the corpus callosum
cingulate gyrus
largest bundle of association fibres?
superior longitudinl fasiculus
how is the basal ganglia linked to parkinsons
degeneration of dopamine neurons in substantia nigra
what makes up the striatum
caudate nucleus and putamen
function of nucleus accumbens
reward centre of the body
What makes up the lentiform nucleus
Globus pallidus and putamen
Function of basal ganglia
Fine tuning of movements
Initiation and control of movements
What is the nigrostriatal pathway
Link between substantia nigra and and striatum
Function of subthalamic nuclei
Assist basal ganglia in regulation of movements
Function and location of amygdala
In temporal lobe
Involved in response to fear
Location of cingulate gyrus
Superior to corpus callosum
Function of papez circuit
Episodic memory consolidation
Basal ganglia direct pathway
Excitatory
Motor cortex projects excitatory fibres to striatum GLUT
striatum inhibits the internal globus pallidus
When the internal gp is inhibited the thalamus is free to activate the motor cortex
Function of indirect pathway
To stop movement
Indirect pathway of basal ganglia
Motor cortex projects excitatory fibres to the striatum
This then sends inhibitory signals to the external gp
If external gp inhibited , the subthalamic nuclei are free to send excitatory signals to the internal gp
Internal gp can inhibit the thalamus
No excitatory fibres sent to the motor cortex
