Week 41 - Neurobiological foundations Flashcards
What are the Brodmann’s areas (BA)?
A map of the brain that divides it into 52 areas, first published in 1909.
What does it mean for neurons to be feature specific?
A single neuron knows only whether it is active or not, and reacts only to very specific stimuli.
What is the principle of distributed coding?
Different features of e.g., visual stimuli are encoded in different places, which means that damage to a small area of the brain does not affect the entire neuronal system, but it also gives rise to the binding problem.
What is the binding problem?
The problem of how our brain combines signals from separate neurons to create coherent experience. Binding separate features encoded through separate neurons into objects.
What are oscillations?
Rhythmic patterns of neuronal activity that can occur in different bands (with different frequencies), such as beta, gamma etc.
What happens during a stroke?
During a stroke, blood is prevented from reaching an area of the brain, and consequently the neurons there die which can cause motoric problems and aphasia.
What does it mean to be environmentally dependent?
Patients automatically perform the action associated with the object they see, e.g., if they see a glass of water, they will drink it.
Name as many brain areas as you can that are involved in the planning and execution of motor actions.
Premotor cortex, motor cortex, supplementary motor area, cerebellum, basal ganglia, dorsolateral prefrontal cortex, orbitofrontal cortex and the anterior cingulate cortex.
What is alien hand syndrome?
Patients know that they are doing a specific movement but cannot report on it (they lack a feeling of intentionality).
What is ataxia?
A lack of coordination with motor actions.
What are forward models and which part of the brain creates forward models?
The cerebellum creates forward models that predict the consequences of the motor actions being performed.
What is bradykinesia?
Retardation of movements, e.g., the timing becomes slower.
How does damage to the basal ganglia affect Parkinson’s disease patients differently compared to Huntington’s disease patients?
For Parkinson’s patients it becomes more difficult to initiate movements, whilst for Huntington’s disease patients it becomes harder to inhibit movements.
What does the premotor cortex do?
Together with primary motor cortex it controls complex and coordinated movements, represented in a somatotopic map. On its own the premotor cortex is involved in perception of movements.
What are the tasks of the motor cortex?
Motor programming; final station in the action control of humans and provides muscular activation, executing what has been planned by other cortical systems
What does the supplementary motor area (SMA) do?
Motor planning; medial part of the premotor cortex, important for selection, planning, and sequencing of goal-directed actions; one of most important information sources for the primary motor cortex
How is the cerebellum involved in action?
Forward modeling; receives input from the motor cortex and almost all sensory areas of cerebral cortex; predicts the sensory consequences of concrete movements and controls motor learning.
What are inverse models?
Provide information about which motor commands are required to achieve specific movement effects—like how the hand can be controlled to grasp a coffee cup in a specific location.
What role does the basal ganglia play in regard to motor action?
Dopaminergic modulation; collection of subcortical nuclei that function to produce dopamine (a neurotransmitter) that influences action regulation as well as the acquisition of cognitive + motor skills.
How is the dorsolateral prefrontal cortex (DLPFC) involved in action?
Goal representation; responsible for the activation, implementation, and configuration of executive processes which coordinate our actions and adapt them to changing conditions.
How is the anterior cingulate cortex (ACC) involved in action?
Action monitoring; monitors our actions and their success, and signals the DLPFC when updating of action goals would be beneficial.
How is the Orbitofrontal cortex (OFC) involved in action?
Action evaluation; responsible for computing / making available the expected rewards of our actions; involved in affective processes.
What are affective processes
Processes involved in action planning in orbitofrontal cortex (OFC). The often intuitive and relatively fast decisions are based on the affective consequences of the actions (which will feel best).
What are somatic markers?
Representations of expected affective bodily reactions, allowing relatively fast and often intuitive decisions i.e. the ones that “feel best”
Why is the production of dopamine important in regards to motor actions?
Dopamine production by the basal ganglia is important because it is a very influential neurotransmitter that modulates numerous motor processes, and also directly influences action regulation.
What is Huntington’s disease?
Disorder caused by damage to the striatum, leading to decreased inhibitory control over movements, resulting in involuntary, fast, jerky movements along with gait and postural instability.
What is Parkinson’s disease?
Disorder caused by damage to the substanita nigra, leading to the loss of dopamine-producing neurons, resulting in symptoms like bradykinesia, rigor, rest tremors, and overall difficulty in initiating voluntary movements.
