16 - 2025 Telencephalon & Cerebral Cortex

What is the primary organization structure of the telencephalon?

The telencephalon consists of two large hemispheres separated by the longitudinal fissure, with outer cerebral cortex and inner subcortical white matter.

How many layers are evident in the neocortex?

The neocortex has six layers evident at some stage of development.

What are pyramidal cells?

Pyramidal cells are the primary efferent neuron of the cortex, characterized by extensive axonal collaterals and an apical dendritic tree.

What is the main neurotransmitter used by cortical interneurons?

Cortical interneurons primarily use GABA as a neurotransmitter.

What characterizes the external granular layer of the neocortex?

The external granular layer is characterized by small to medium-sized cells that contribute to cortical circuits.

What is the function of layer IV in the neocortex?

Layer IV is known as the 'primary receptive layer' and receives afferents from thalamocortical sources.

What is the difference between homotypical and heterotypical cortex?

Homotypical cortex has all six layers clearly definable and roughly equal, while heterotypical cortex has some layers that are not well defined.

What is the key functional area associated with the primary motor cortex?

The primary motor cortex is located in Brodmann's area 4 in the precentral gyrus and is responsible for the control of movement.

Which area is known for language comprehension?

Wernicke area, primarily located in the superior temporal gyrus of the dominant hemisphere.

What are the major symptoms of Broca's aphasia?

Broca's aphasia is characterized by decreased fluency of speech with short phrases and relatively preserved comprehension.

What is the role of the anterior commissure in the brain?

The anterior commissure connects the two hemispheres of the brain and facilitates communication between them.

What is the primary function of the posterior parietal association cortex?

It is involved in the integration of sensory information and attention to spatial aspects of sensation.

What are the signs of a prefrontal lesion?

Signs include disinhibition, abulia, confabulation, perseveration, and diminished ability to generate lists.

What is the anatomical location of the primary somatosensory area?

The primary somatosensory area is located in Brodmann's areas 3, 1, and 2, along the postcentral gyrus.

What are the main types of projection fibers?

The major types include corona radiata and internal capsule, connecting the cortex to subcortical structures.

Compare the dominant and non-dominant hemispheres in terms of function.

The dominant hemisphere typically handles language and analytical tasks, while the non-dominant hemisphere is involved in visual-spatial processing and emotional aspects of language.

What neurotransmitter is primarily associated with excitatory signals in the cerebral cortex?

Glutamate is primarily associated with excitatory signals.

What is the function of the supplementary motor area (SMA)?

The SMA is responsible for planning movements, especially those involving interlimb coordination.

Define agnosia in the context of neuropsychology.

Agnosia is the inability to recognize or interpret familiar objects, despite having intact sensory functions.

What is the primary function of the basal ganglia?

The basal ganglia are primarily involved in the regulation of movement and motor control.

What is neuroplasticity?

Neuroplasticity is the brain's ability to reorganize itself by forming new neural connections in response to learning or injury.

What is the function of the cerebellum?

The cerebellum coordinates voluntary movements, balance, and motor learning.

What are the major types of cerebral white matter fibers?

The major types include association fibers, commissural fibers, and projection fibers.

What is the function of the thalamus?

The thalamus acts as a relay station for sensory information, directing it to the appropriate cortical areas.

What is the significance of the hippocampus?

The hippocampus is crucial for memory formation and spatial navigation.

What role does the amygdala play in the brain?

The amygdala is involved in processing emotions and is particularly important for fear and pleasure responses.

What is the difference between gray matter and white matter in the brain?

Gray matter consists of neuronal cell bodies, while white matter is made up of myelinated axons.

Describe the function of the frontal lobe.

The frontal lobe is responsible for higher cognitive functions, including reasoning, problem-solving, and planning.

What is the difference between gray matter and white matter in the brain?

Gray matter consists of neuronal cell bodies, while white matter is made up of myelinated axons.