Cerebral Cortex Flashcards
What are the three types of fibers?
Projection Fibers, Callosal/commisural fibers, and association fibers
Layers of the Neocortex
6
Layer 1 of Neocortex
Plexiform Layer
Has very few cell bodies
Layer 2 of Neocortex
External Granule Layer
Made of Granule and Pyramidal Cells
- One of two layers giving rise to association fibers
Layer 3 of Neocortex
External Pyramidal Layer
Made of smaller Pyramidal Cells
- One of two layers giving rise to association fibers
Layer 4 of Neocortex
Internal Granule Layer
Interneurons
Main input zone
Layer 5 of Neocortex
Internal Pyramidal Layer
Predominantly larger pyramidal cells
Main output zone
Layer 6 of Neocortex
Multiform Layer
made of multiple cell types
Axons here project to subcortical targets
Homotypical Cortex
All 6 layers are clearly represented in most of cortex
Heterotypic Granular Cortex
Layers vary in thickness
Layer 4 is especially thick while layer 5 is especially thin
Primary Somatosensory Cortex is like this
Hereotypic Agranular Cortex
Layers vary in thickness
Layer 5 is especially thick while layer 4 is especially thin
Primary Motor Cortex is like this
Functional Categories of Cerebral Cortex
Motor
Primary Sensory
Association Areas
What areas of Cortex are the Motor Area
Primary motor cortex, SMA, and Premotor cortex
Primary Motor Cortex
Precentral and anterior paracentral gyri of frontal lobe
- Sends motor output to contralateral side of body
Primary Somatosensory Cortex
Postcentral and posterior paracentral gyri of parietal lobe
Receives sensory input from contralateral side of body
Primary Auditory Cortex
Transverse temporal gyri located deep in lateral sulcus
Receives auditory input from both ears
Primary Visual Cortex
Upper and Lower banks of calcarine sulcus in medial occipital lobe
Receives visual input from contralateral field
Unimodal Association Areas
Areas that are adjacent and related to primary areas
Multimodal Association Areas
Large areas of cortex which receive information from several different sensory modalities and create a broader more complete understanding of outselves and environment
Lateralization
Different parts of brain or hemispheres are responsible for different functions
Right: Helps explain context
Left: Understanding fine detail
Where is attention located
Frontal and Parietal association areas
Attention Capture
Automatic or reflexive orienting to a stimulus
Selective Attention
Goal directed focus of attention with ability to ignore irrelevant stimuli
Sustained Attention
Ability to maintain vigilance over time
Divided Attention
Ability to preform 2 or more tasks at same time or process 2+ sources of info at the same time
Alternating Attention/Task Switching
Rapidly switching between different skills, tasks, or cognitive sets
Where is receptive and expressive language localized in cortex?
Frontal and temporal association areas
Structure for repeating a heard word
Primary auditory cortex hears word –> Wernickes Area for understanding of speech –> to Brocas area for formulation of speech motor plan –> Primary Motor cortex for speech production
Structure for Speaking Written word
Primary visual cortex sees word –> To inferior parietal lobe –> Wernickes Area for comprehension –> To Brocas for motor plan –> Primary Motor cortex for speech production
