functies van (sub)structuren Flashcards
basal Ganglia
The basal ganglia comprise a group of structures that regulate the initiation of movements, balance, eye movements, and posture. They are strongly connected to other motor areas in the brain and link the thalamus with the motor cortex. The basal ganglia are also involved in cognitive and emotional behaviors and play an important role in reward and reinforcement, addictive behaviors and habit formation.
brain stem
The brain stem consists of a group of structures that lie deep within the brain, including the pons, medulla oblongata, and midbrain. It plays an important role in maintaining homeostasis by controlling autonomic functions such as breathing, heart rate, and blood pressure. While the brain stem can organize motor movements such as reflexes, it coordinates with the motor cortex and associated areas to contribute to fine movements of limbs and the face.
the pons
The pons is the region in the brain most closely associated with breathing and with circuits that generate respiratory rhythms. It forms a bridge between the cerebrum and cerebellum and is involved in motor control, posture, and balance. It is also involved in sensory analysis and is the site at which auditory information enters the brain.
cerebellum
The cerebellum monitors and regulates motor behavior, particularly automatic movements. Some recent studies have associated the cerebellum with cognitive functions, such as learning and attention. Although the cerebellum accounts for roughly 10% of total brain weight, it contains more neurons than the rest of the brain combined. The cerebellum is also one of the few mammalian brain structures where adult neurogenesis (the development of new neurons) has been confirmed.
corpus Callosum
The corpus callosum consists of a large bundle of fibers connecting the right and left hemispheres of the brain. Each hemisphere controls movement in the opposite (contralateral) side of the body and can also specialize in performing specific cognitive and perceptual functions. The corpus callosum allows information to move between hemispheres and is therefore a very important integrative structure.
the frontal lobe
The frontal lobes are part of the cerebral cortex and are the largest of the brain’s structures. They are the main site of so–called ‘higher’ cognitive functions. The frontal lobes contain a number of important substructures, including the prefrontal cortex, orbitofrontal cortex, motor and premotor cortices, and Broca’s area. These substructures are involved in attention and thought, voluntary movement, decision–making, and language.
Broca’s Area
Broca’s area is a functionally defined structure in the left frontal lobe of about 97% of humans (including a large majority of left–handers). Broca’s area is involved mainly in the production of spoken and written language and also in language processing and comprehension. It takes its name from the French scientist whose work with language–impaired patients led him to conclude that we speak with our left–brain.
prefrontal cortex
The prefrontal cortex is thought to play an important role in “higher” brain functions. It is a critical part of the executive system, which refers to planning, reasoning, and judgment. It is also involved in personality and emotion by contributing to the assessment and control of appropriate social behaviors.
premotor cortex
The premotor cortex consists of a narrow region between the prefrontal and motor cortices. It is involved in preparing and executing limb movements and uses information from other cortical regions to select appropriate movements. The premotor cortex is also important for learning (imitation) and social cognition (empathy) – mirror neurons in the premotor cortex area of the macaque brain fire when the animal observes an action in others.
primary motor cortex
The primary motor cortex (also known as M1) is critical to initiating motor movements. Areas of the motor cortex correspond precisely to specific body parts. For example, leg movements map to the part of the motor cortex closest to the midline. Not all body parts are equally represented by surface area or cell density – representations of the arm hand motor area occupy the most space in the motor cortex (unsurprising given their importance to human behavior). Similarly, representations in the motor cortex can become relatively large or small with practice/training.
limbic system
The limbic system is a group of brain structures including the amygdala, hippocampus, and hypothalamus that are involved in processing and regulating emotions, memory, and sexual arousal. The limbic system is an important element of the body’s response to stress and is highly connected to the endocrine and autonomic nervous systems. The limbic system is also responsible for processing the body’s response to odors.
amygdala
The amygdala is a complex structure adjacent to the hippocampus. The amygdala is involved in processing emotions, and fear–learning. It links areas of the cortex that process “higher” cognitive information with hypothalamic and brainstem systems that control “lower” metabolic responses (e.g. touch, pain sensitivity, and respiration). This allows the amygdala to coordinate physiological responses based on cognitive information – the most well–known example being the fight–or–flight response.
The amygdala has three functionally distinct parts – 1) the medial group of subnuclei has many connections with the olfactory bulb and olfactory cortex, 2) the basolateral group has extensive connections with the cerebral cortex, particularly the orbital and medial prefrontal cortex, and 3) the central and anterior group of nuclei has many connections with the brainstem hypothalamus, and sensory structures.
cingulate cortex
An important part of the limbic system, the cingulate gyrus helps regulate emotions and pain. The cingulate gyrus is thought to directly drive the body’s conscious response to unpleasant experiences. In addition, it is involved in fear and the prediction (and avoidance) of negative consequences and can help orient the body away from negative stimuli. Learning to avoid negative consequences is an important feature of memory.
dentate gyrus
The hippocampal formation has three regions, which are highly interconnected: the dentate gyrus, CA3, and CA1. It is one of the very few regions in the brain where adult neurogenesis (development of new neurons) has been confirmed. The dentate gyrus may play an important role in translating complex neural codes from cortical areas into simper code that can be used by the hippocampus to form new memories.
entorhinal cortex
The entorhinal cortex plays a major role in memory formation. Two major connections from the entorhinal area (lateral and medial) provide the main input to the hippocampus and are important to pre–processing memorable information. The lateral input stream is thought to convey spatial information to the hippocampus, while the medial input stream conveys nonspatial information. The stream of information from the entorhinal cortex, through the dentate gyrus, to the hippocampus is called the perforant path.
