Cerebral cortex

Primates

Monkeys, apes and humans; have a larger cerebral cortex with more folding and neurons.

Coritcal topography

Wilder enfield; the practice of mapping out the functions of different brain areas

• topographic map of body parts corresponding with brain areas.

• Also looked at the homunculus’

• Sensory homunculus (behind central sulcus) within the postcentral gyrus

  • Motor homunculus (infront of central sulcus containing the precentral gyrus)

Brodmann’s Map

Identified 52 areas based on cytoaritectonic trends.

Gyrus

A bump or portrusion

Cortical layers

6 stacked layers that have unique combinations of cell types.

Cortical columns

White matter tracts deep in the cortex

Corpus callosum

Axons running along the middle of the brain, involved in inter-hemispheric transfer of information.

4 Sulcus/Fissures

Central sulcus, lateral (sylvian) fissure, longitudinal fissure, Pareto-occipital sulcus, cingulate sulcus.

Occipital lobe

A lobe at the posterior end of the cortex separated from the parietal lobr with the Pareto-occipital sulcus and the main target for visual information.

Primary visual cortex

The primary visual cortex is located in the occipital lobe of the brain and is responsible for processing visual information received from the eyes. It plays a crucial role in visual perception and interpretation.

Cuneus

Represents the lower visual field, the foceal region is overrepresented.

Lingual gyrus

Represents the upper visual field.

Calcarine sulcus

Separates the cuneus and lingual gyrus.

Parietal lobe

Lies between occipital lobe and central sulcus; processes sensory information

Post central gyrus/primary somatosensory cortex

Recieves sensations from touch receptors, muscle and joint receptors.

• Located on parietal lobe between central sulcus and postcentral sulcus

• integrates internal states and external information/goals.

• 4 bands of cells receives simultaneous info from different parts of the body.

Numerical cognition

Ability to do math/represent numbers.

Apraxia

Left inferior parietal lobe damage; affects movements.

Neglect

Damage to right inferior parietal lobe.

Temporal lobe

the lateral portion of each hemisphere near the temples, divided by the lateral (sylvan) fissure, primary cortical target for auditory information.

• left temporal lobe essential for speech

Hluver-Bucy syndrome

A set of behaviours caused by damage to temporal lobe: inappropriate sexual behaviours, overeating and excessive other mouth movements.

Temporoparietal junction

The area where the parietal lobe and temporal lobe meet; relieves input from vision, hearing and body senses.

Superior temporal lobe

Containing the primary and secondary auditory cortex, and Wernicke’s area (language comprehension).

Inferior temporal lobe

visual object recognition and agnosia and prosopagnosia.

Medial temporal lobe

emotional processing (amygdala), memory (hippocampus).

Frontal lobe

a section of the cerebral cortex that extends from the central sulcus to the anterior limit of the brain; contains the prefrontal cortex, premotor cortex, primary motor cortex and supplementary motor area.

Prefrontal cortex

the most anterior portion of the frontal lobe; contains default network, dominate activity when you don't need to concentrate; mostly works with executive functioning, control, emotions.

Primary motor cortex/precentral gyrus

in front of the somatosensory cortex with 3 major regions; posterior (movement), middle zone (cognitive control emotional reactions and memories) and anterior zone (making decisions and evaluating what actions should be chosen).

Premotor cortex

Located anterior to the primary motor cortex, involved in planning and organizing movement and actions.

Supplementary motor area

Located on the midline surface of the hemisphere anterior to the primary motor cortex leg representation, contributes to the control of movement.

Prefrontal lobotomy

surgery that consists of damaging the prefrontal cortex or cutting its connections to the rest of the cortex; caused apathy, lack of initiative. distractibility, lack of emotional expression.

Limbic lobe

2 gyri surrounding corpus callosum. separated fromt he outer lobes by the cingulate sulcus, incolved in emotion and containing the anterior cingulate cortex, posterior cingulate cortex, and parrahipocampla gyrus.

Anterior cingulate cortex (ACC)

emotion and pain related motor movements, cognitive control and detecting errors, anticipating rewards.

Posterior cingulate cortex (PCC)

Monitoring eye movements, spatial orientation, memory.

Parahippocampal gyrus

Memory

Binding problem

aka the large-scale integration problem, questions how various brain areas produce a perception of a single object.

• Binding requires identifying the location of an object and perceiving all aspects of a stimulus as being simultaneous. We bind 2 stimulus from same location at same time as a single experience.

Cholinergic system

Few areas that mainly release Acetylcholine:

• Neurons release ACH in the basal forebrain project to the cortex and limbic system

• Neurons releasing ACH from the pons and midbrain project to the amygdala, thalamus, brainstem and cerebellum.

  • Laterodorsal Tegmental Nucleus (LDT)

  • Perdunculopontine Nucleus (PPN)

Dopaminergic system

Few areas that mainly release dopamine; consisting of the mesocortical, mesolimbic and nigrostratal system.

Mesocortical system

Dopminergic neurons that project from the VTA to cerebral cortex

Mesolimbic system

Dopaminergic neurons projecting from the VTA to limbic structures and the basal ganglia (ex. nucleus accumbens)

Nigrostratal system

Neurons that release dopamine from the substantial nigra and project to basal ganglia.

Noradrenergic system

Areas that mainly release norepinephrine from locus coereleus to project to various parts of the brain.

Senotonergic system

Neurons that release seratonin from the raphe nuclei of the brainsytem and project to most of the brian.