13. Deincepheleon + cerebrum

Deincephaleon

• Between BS and cerebrum

• 4 components

  • thalamus

  • subthalamus

  • epithalamus

  • hypothalamus

Thalamus

• 2 paired oval shape masses

  • conencted by interthalamic adhesion

    • gray mater adhesion

• superior

• recives major part of sensory input

  • projections to cerebral cortex (CC) (excetpt smell)

  • helps filter sensory info

• Auditory impulses

  • medial geniculate nucleus

    • take info from inner ear then bring them to primary auditory area of CC

• visual impulses

  • Latral geneculate nucleus

    • Gather info from retenia from eye then takes it to primary visual area of CC

Subthalamus

• Inferior to thalamus

• Has both as/decending NT (nerve tratcs)

  • mostly white mater

• subthalamic nuclei

  • lots of gray mater

  • central motor function

Epithalamus

• Posterior + superior to thalamus

• made up of 2 parts

  1. Habenula

     • superior

     • Motivational control of behvaior

       • intergrative role linked to behvaiors that involve rewards

         • (may be linked to addiction)

     • Regulates emotional state, decision making, integrating sensory info, cognitive, emotional info

     • encodes for rewarding adverse aspects to stimuli

       • influence behavior

     • dysfunction in this region

       • linked to:

         • addiction

         • schizophernia

  2. PIneal Gland

     • inferior

     • pine cone shaped

     • size of pea

     • biological clock

       • linked to timing + growth to development

         • Ex: onset of puberty

       • May secrete chemicals

         • cuase signal cascades of events

           • bring of physiological change during puberty

           • also changes later in life like menopause

       • secretes melatonin

         • promotes sleepiness

         • linked to sleep

         • when your asleep melatonin produced

           • helps keep you asleep

         • melatonin in light sensitive

           • when you see light melatonin drops

           • 
             

Hypothalmaus

• anterior

• inferior (most in deincephelon)

• connects to pituitary gland (master gland)

• connection betwen nervous/endocrine system

• infundibulum

  • stalk inside HT (hypothalamus)

  • connects to PG (pituitary gland)

    • sercretes hormonoes to do many body functions

      • Ex:

        • metabolism

        • reproduction

        • stress response

        • urine production

  • makde of white matter + connective tissue

  • links between nervous/endocrine systems

• Back to HT

  • has many clusters of nuclei

    • central bodyily functions

  • more than 12 different nucliei

    • important for homeostasis

  • in some of nuclei involved in

    • autonomic control on

      • heart rate

      • BP

      • respiration

      • digestion

      • hunger

      • thrist

      • body temp

      • moods

      • emotion

      • sex drive

• one are of HT affected can cause another region to be affected

• plays role in visceral + emotional resposnse to odors

• Preoptic area

  • involved in thermoregulation

  • close to optic chisam

Cerebrum

• Largest region

• involved in concious processes

• intellectual function

• higher level

  • planning

  • reasoing

  • organizing thoughts

  • accessing/storing memory

  • interpreting sensory info

  • alicting motor responses

Cerebral cortex

• Part of cerebrum

• outer layer

• gray matter

subparts:

1. gyri (gyrus ← Singular)

   • characteristic folds on cerebral cortex

2. sulci (sulcus ← singular)

   • shallow groves

3. Fissures

   • deeper groves

Central sulcus

• Part of cerebral cortex

• runs middle of brain

• separates lobes

  • frontal

  • parietal

Precentral Gyrus

• Anterior to central sulcus

• part of cerebral cortex

• locattion of primary motor cortex

  • gray matter

  • initiates majority of motor responses in body

Postcentral Gyrus

• Primary somatiosensory cortex (located here)

• part of cerebral cortex

• most of sensory info interpreited here

  • not include

    • vision

    • hearing

    • smell

Deep clusters of nuclei

• gray matter

• basal nuclei

  • involved in motor functions

Cerebral medulla

• In between of deep clusters of nuclei and cerebral cortex

• white matter

• all mylinated axons pahways connect different gray matter regions within cerebrum

• And they connect to other regions of the brain

Longitudinal Fissure

• separates left/right cerebrum

Frontal lobe

function

• motor function

• agression + mood

Parital lobe

• Sensory info site

• not smell, taste, vision, hearing

Ex:

• touch

• pressure

• moniters blood pH

Pareitoccipital sulcus

• separates parital and occipital lobe

Occipital lobe

• Perception of visual input

  • location of the visual cortex

Lateral fissue (lateral cerebral sulcus)

• separates frontal + temporal lobe

Temporal lobe

• Involved in sense of smell or olfactory sense

• auditory interpretation

• forming + accesing memories

Deep inside cerebrum

• 5th lobe

  • insula

    • plays role in

      • homeostasis

      • selfawareness

      • emotion

      • associated with sense : taste

Cerebral medulla

• NT’s connect the cortex to other areas of cortes or other parts of the CNS

  • white matter

3 main types of fibers/tracts found in cerebrum:

1. association tract

   • connect areas of CC within some hemisphere

2. Commisural tracts

   • connect the cerebral hemispheres

     • corpus callosum

3. Projection tracts

   • run between cerebrum + other parts of brain + SC

   • Bundles of these makes

     • internal capsule