Biopsychology (

somatic nervous system:

• consists of axons conveying messages from the sense organs to the CNS and from the CNS to the muscles

autonomic nervous system

• controls the heart, intestines, and other organs

→ has some cell bodies within the brain or spinal cord or in clusters along the sides of the spinal cord

What is the Bell-Magendie law?

• entering dorsal roots carry sensory info, and exiting ventral roots carry motor info

What does dorsal mean?

• towards the back

What does ventral mean?

• towards the stomach

What is the spinal cord comprised of?

• grey matter

• white matter

What is Grey matter?

• located in the center of the spinal cord & is densely packed with cell bodies & dendrites

What is White matter?

• composed mostly of myelinated axons that carry info from the grey matter to the brain or other areas of the spinal cord

What does the autonomic nervous system do?

• sends and receives messages to regulate the automatic behaviors of the body (heart rate, blood pressure, respiration, digestion, etc.)

What are the 2 subsystems of the Autonomic Nervous System?

• The sympathetic nervous system

• The parasympathetic nervous system

Sympathetic nervous system

• It is a network of nerves that prepares the organs for rigorous activity:

  • “SPEEDS UP”

  → increases heart rate, blood pressure

  → norepinephrine

Parasympathetic nervous system

• it facilitates vegetative, non-emergency response

  • “BRINGING BACK DOWN”

  → decreases functions increased by the sympathetic nervous system

  → acetylcholine

What are the 3 major divisions of the brain?

• hindbrain

• forebrain

• midbrain

What does the Hindbrain consist of?

• medulla

• pons

• cerebellum

  →is located at the posterior portion of the brain

What is the Brain Stem?

• hindbrain structures + the midbrain + other central structures of the brain

Medulla

• could be regarded as an enlarged extension of the spinal cord

  → vital reflexes such as breathing, heart rate, vomiting, salivation, coughing, and sneezing

Pons

• lies on each side of the medulla

• along with the medulla, contains the reticular formation & raphe system

• works in conjunction to increase the arousal and readiness of other parts of the brain

Cerebellum

• structure located in the hindbrain w/ many deep folds

• helps regulate motor movement, balance, and coordination

• also important for shifting attention between auditory and visual stimuli

What are cranial nerves?

• they allow the medulla to control sensations from the head, muscle movements in the head, and many parasympathetic outputs to the organs

What does the Reticular Formation do?

• descending portion is one of several brain areas that control the motor areas of the spinal cord

• ascending portion sends output to much of the cerebral cortex. selectively increasing arousal and attention

What does the raphe system do?

• sends axons to much of the forebrain, modifying the brain’s readiness to respond to stumli

What does the Midbrain consists of?

• tectum (roof of midbrain)

• superior colliculus & inferior colliculus (processes sensory info)

• tegmentum (contains nuclei for cranial nerves and part of the reticular formation

• substantia nigra: gives rise to the dopamine-containing pathway facilitating readiness for movement

Tectum

• roof of the midbrain

Superior colliculus & Inferior colliculus

• processes sensory info

Tegmentum

• contains nuclei for cranial nerves and part of the reticular formation

Substantia nigra

• gives rise to the dopamine-containing pathway

What does the Forebrain consists of?

• thalamus

• hypothalamus

• cerebral cortex

• hippocampus

• basal ganglia

The forebrian is ….

• the most prominent part of the mammalian brain consists of two cerebral hemispheres

• the cerebral cortex = outer portion

• each side receives sensory info and controls motor movement from the opposite (contralateral) side of the body

Thalamus

• relay station from the sensory organs and the main source of input to the cortex

Hypothalamus

• associated w/ behaviors such as eating drinking, sexual behaviors and other motivated behaviors

• small area near the base of the brain

• conveys messages to the pituitary gland to alter the release of hormones

What do the Thalamus and the Hypothalamus form together in the Forebrain?

• diencephalon

Pituitary Gland

• hormone producing gland found at the base of the hypothalamus

Basal Ganglia

• comprised of the caudate nucleus, the putamen, & the globus pallidus (SET OF AREAS AROUND THE BRAIN THAT LIE ON THE DORSAL SURFACE OF THE FOREBRAIN)

→ associated w/ planning of motor movement and aspects of memory & emotional expression

Nucleus Basalis

• sends axons that release acetylcholine to the cerebral cortex

• key part of the brain’s system for arousal, wakefulness, and attention

• receives input from the hypothalamus and basal ganglia

Hippocampus

• critical for storing certain types of memory, particularly new events (consolidation)

• large structure located between the thalamus and the cerebral cortex

Central canal

• fluid-filled channel in the center of the spinal cord

Ventricles

• Four fluid-filled cavities within the brain containing cerebrospinal fluid

Cerebrospinal fluid (CSF)

• a clear liquid found in the brain and spinal cord

  • provides “cushioning” for the brain

  • reservoir of hormones and nutrition for the brain & spinal cord

  • produced by the choroid plexus that lines the ventricles

Meninges

• are membranes that surround the brain and spinal cord

  • if the meninges get infected, it can cause meningitis

• the brain has no pain receptors but the meninges do

• swollen blood vessels in the meninges are the cause of migraine headaches

cerebral cortex

• most prominent part of the mammalian brain

migration

• movement of the newly formed neurons and glia to their eventual locations

  • some don’t reach their destination until adulthood

  • Occurs via cells following chemical paths

differentation

• the forming of the axona