Neocortex
The neocortex (also called the neopallium, isocortex, or the six-layered cortex), is a set of layers of the mammalian cerebral cortex involved in higher-order brain functions such as sensory perception, cognition, generation of motor commands,[1] spatial reasoning and language.
The neocortex is the largest part of the cerebral cortex and is responsible for higher-order brain functions such as sensory perception, cognition, and motor control. It is characterized by six layers:
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Layer I (Molecular layer): Contains few neurons, mainly dendrites from deeper layers and axons from other cortical regions. It plays a role in integrating sensory information.
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Layer II (External granular layer): Contains small pyramidal neurons and is involved in cortical communication.
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Layer III (External pyramidal layer): Contains medium-sized pyramidal neurons that send projections to other cortical regions and subcortical areas.
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Layer IV (Internal granular layer): Receives sensory input from the thalamus. This layer plays a key role in sensory processing.
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Layer V (Internal pyramidal layer): Contains large pyramidal neurons that send outputs to subcortical structures like the brainstem and spinal cord.
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Layer VI (Multiform layer): Sends feedback projections to the thalamus, influencing sensory processing.
Projections:
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The neocortex has long-range projections to other cortical regions and subcortical structures. These projections are involved in higher cognitive functions, including memory, learning, and decision-making.
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The neocortex also receives input from the thalamus, which relays sensory and motor signals.
Functions:
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The neocortex is responsible for complex sensory processing, motor control, conscious thought, decision-making, language, and problem-solving. Different regions of the neocortex are specialized for tasks such as visual processing (occipital lobe), auditory processing (temporal lobe), and motor control (frontal lobe).
Allocortex
The allocortex is an older part of the cortex that has fewer layers (typically three or four) and is primarily involved in emotion, memory, and instinctive behaviors. The allocortex includes regions such as the hippocampus, olfactory cortex, and parts of the limbic system.
Allocortex
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The neocortex is responsible for higher cognitive functions, sensory processing, and motor control, with six distinct layers facilitating complex neural interactions and projections.
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The allocortex is involved in primal functions like memory, emotion, and motivation, with fewer layers and connections to limbic structures that regulate behavior and autonomic responses. Both cortical regions work together to enable the brain to perform a vast array of cognitive and emotional tasks.