Chapter 3 Flashcards
Main functional pathways.
Define the relationship between the serotonergic, noradrenergic and cholinergic systems in relation to the ARAS.
Locus Coeruleus (Noradrenaline) and the Dorsal Raphe Nuclei (Serotonine) project both to the nucleus basalis of Meynert (acetylcholine). Serotonine inhibits, whole Nordadrenaline activates. In this way they mediate the cholinergic system.
Describe the frontocerebellar circuit, referring to its anatomy and function.
the frontocerebellar circuit runs from the prefrontal cortex, via the anterior cingulate to the cerebellum. It is involved in executive functions and responsible for maximizing processing speed. Moreover, it plays a role in episodic memory (importance of executive functions!).
The basal forebrain consists of …
medial septal nuclei (septum), nucleus basalis of Meynert (NBM), diagonal band and substantia innominata (containing the NBM)
In which neurodegernative diseases is the basal forebrain affected?
Alzheimer’s disease, Parkinson’s disease, Down’s syndrome, Korsakoff’s syndrome and Pick’s disease.
Describe the frontostriatal circuit, referring to its anatomy and function.
Several bundles connect motor areas with the striatum:
(1) two connect primary motor cortex and the DLPFC with the lateral and medial putamen.
(2) the premotor area is connected with the dorsal posterior putamen.
(3) the supplementary motor area and the VLPFC are connected with the ventral anterior caudate nucleus.
(4) the DLPFC shows a functional relationship with the dorsal posterior caudate nucleus.
Innervated by the dopaminergic system (origin: substantia nigra). Involved in maintenance of executive functions, episodic memory and motor-related activities (e.g. balance + initiation of activity).
Describe the frontohippocampal circuit, referring to its anatomy and function.
Strong connections from hippocampus, via the entorhinal cortex into the prefrontal cortex.
Contributes to attention, executive functions and memory (e.g. episodic and working memory).
Describe the nigrostriatal circuit, referring to its anatomy and function.
Originates in substantia nigra, connects with striatum, extends bidirectionally. From SN to anterior regions, including PFC and laterally to hippocampus.
Highly involved in facilitating smooth movement. Lesion can lead to (pseudo-)parkinsonism symptoms.
Describe the hippoparietal circuit, referring to its anatomy and function.
Strong connections from hippocampus to thalamus, parahippocampal cortex and superior as well as lateral parietal cortex.
Vital for integration of sensors inputs, facilitation of executive functions (e.g. working memory) and visuospatial functions.
Describe the superior longitudinal fasciculus, referring to its anatomy and function.
SLF connects all lobes (frontal, tempora, parietal and occipital).
Responsible for gait and motor related functions, as imagination of gait (or foot movement), inhibitory motion control and preparation of voluntary movement. Also plays a role in working memory, visuospatial attention and selective attention.
Describe the uncinate fasciculus, referring to its anatomy and function.
UF connects orbitofrontal cortex, DLPFC, subgenual anterior cingulate cortex and the anterior and inferior lateral temporal lobes.
Responsible for gait and motor functions, such as spatial navigation, as well as head and trunk stabilization. Also involved in language, executive functions, learning and memory.
Describe the cingulum, referring to its anatomy and function.
Longest pathway: connects uncus and parahippocampal gyrus to the subrostral frontal areas.
Short pathways: connect medial frontral gyrus, posterior parietal lobe, cuneus, lingual and fusiform gyrus.
Involved in gait and motor functions, e.g. imagery of walking, head direction and coordination of complex foot movements.
