Disconnection syndromes Flashcards
How is described the SWM according to Watts and Strogatz (1998)?
Described as networks presenting
- High local cluster coefficient = Nodes within a small-world network have dense local connections
- Low minimal path length btw pair of nodes= Despite local clustering, the network maintains efficient global communication through a few long-range connections (shortcuts).
How is described the SWM according to Wang et al. (2010)?
SMW with the dvlp of a network being related to a general decrease in short-range with simultaneous increase in long range connections.
Def Nodes
= Peripheral connection point inside the network (or = indicidual units in the network)
(eg: neurons)
Def modules
= Nodes with larger connectivity degree
(allow for localized processing of specific types of infos)
Def hubs
modules that connect to other modules, also other clusters entirely
(eg : aCC, mCC, pCC are hubs)
What happens when hubs are damaged?
The info can still be process but it can”t be moved foward to be actioned (=no action)
Explain what is DMN = Default mode network
It’s the original state of the person, when there is no action (eg : day dremaing, planning).
It’s a resting or task negative network of “stimulus in dependent thought” that realtes to all internal cognitive processes happening in the absence of immediate stimulation that will promote an increase in brain activity
What are the characteristic of the DMN
- It only takes into consideration the 2ndary area
- It excludes the primary area
Which area are the most concerned by DMN?
HPC-AM-OFC-mPFC;vlPFC;PFC;mvPFC-aCC-mCC-pCC-TP-CAU-THA-Cb
What are the general sumptoms of Apraxia?
in case of LBD
- Imitation
- gesticulation used for communication
- tool use
Sequential movements (ADLS)
What model describes the brain’s operation as a combination of local clustering and long-range connections?
Small World Model
This organization enables efficient information transfer while minimizing energy costs.
What are nodes in the context of network architecture in the brain?
Peripheral connection points representing distinct brain regions or functional areas
Nodes act as processing centers for specific cognitive functions.
What are modules in the network architecture of the brain?
Collections of densely interconnected nodes with larger connectivity degree
Modules form specialized functional units enabling efficient local processing.
What is the function of hubs in brain network architecture?
Modules that connect to other modules and clusters, critical for integration of information
Vulnerability to damage can lead to widespread dysfunction.
What are the key regions of the Default Mode Network (DMN)?
medial prefrontal cortex (mPFC), posterior cingulate cortex (pCC), precuneus
These regions participate in functions such as episodic memory retrieval and imagining future events.
During what state is the Default Mode Network (DMN) active?
During rest and task-negative network of ‘stimulus independent thought’
This involves internal cognitive processes in the absence of immediate stimulation.
What deficits are linked to dysfunction in the Default Mode Network (DMN)?
Ideomotor and ideational deficits
Ideomotor deficit relates to translating a mental image into intended motor action, while ideational deficit involves constructing a mental image to follow during motor action.
What is the role of the Frontoparietal Network (FPN)?
Responsible for modulating behavioral responses and creating context for analysis and interpretation
This directly guides decisions and interactions with the environment and others.
What is the primary function of the Frontoparietal Network (FPN)?
Cognitive control and executive function, including movement planning and execution
Dysfunction in this network is linked to motor planning and cognitive deficits.
Fill in the blank: The brain functions as a _______ network, allowing for specialized functions while maintaining global connectivity.
small world
True or False: The Default Mode Network (DMN) includes primary areas such as V1, M1, and S1.
False
Primary areas are excluded from the DMN.
