PSY 426- Behavioral Neuroscience

chapter 3-exam 1 notes

anatomical directions

dorsal- back of spinal cord, top of brain

ventral-front of spinal cord, bottom of brain

anterior-front of spinal cord, front of brain

posterior-back of spinal cord, back of brain

other anatomical directions

superior-above another structure

inferior-below another structure

lateral-toward the side/away from center

medial- toward middle/away from sides

what is contained in the Central Nervous System (CNS)

• brain

• spinal cord

what is contained in the Peripheral Nervous System (PNS)

• connects brain and spinal cord to the rest of body

  • Somatic Nervous system

  • Autonomic Nervous system

dorsal root v.s. ventral root in spinal cord

dorsal— carries SENSORY (afferent) information to CNS

ventral—carries MOTOR (efferent) information to muscles and glands

Somatic Nervous System

primarily involved in Voluntary movement, although some somatic motor responses are reflexive; responsible for communication btw central nervous system and the body

• carries sensory info. from body to CNS

• carries motor commands from CNS to skeletal muscles

Autonomic Nervous System

sends and receives messages from different parts of the heart, intestines, and other organs.

• has two parts;

  • 1. Sympathetic nervous system

  • 2. parasympathetic nervous system

Sympathetic nervous system; “Fight or Flight”

prepares organs for fight or flight

• causes increased breathing

• increased HR

• decreased digestive activity

• sweat glands & adrenal muscles constrict blood vessels.

• axons release norepinephrine, those sweat glands use acetylchlorine

Parasympathetic nervous system; “Rest and Digest”

facilitates vegetative nonemergency response and conserves energy

• rest&digest; decreased HR, increased digestion

• parasympathetic axons extend from spinal cord to parasympathetic ganglia close to each internal organ

• these axons release acetylcholine onto the organs

spinal cord

communicates all sensory organs & muscles except those in the head

• has diff. segments; each segment sends sensory info to brain and receives motor commands from brain

gray matter v.s. white matter

gray matter: processes information. located at center of spinal cord is densely packed with cell bodies and dendrites.

white matter: facilitates communication btw diff. parts of the nervous system. myelinated axons go through spinal cord to other parts or spinal cord and brain

what are the 3 major parts of the brain?

1. Hindbrain

2. Midbrain

3. Forebrain

parts of the Hindbrain.

• medulla

• pons

• cerebellum

parts of the Midbrain.

• tectum

• superior & inferior colliculus; important for sensory processing

• tegmentum

• substantia nigra; gives rise to dopamine—containing pathway facilitating readiness for movement

parts of the Forebrain.

• Cerebral Cortex (outer portion of the forebrain)

• Thalamus and Basal Ganglia (under cerebral cortex)

• Limbic system

function of medulla

located above spinal cord.

• controls VITAL reflexes(breathing, HR, sneezing, vomiting, etc.)

• damage to this area is life-threatening, b/c opiates shut off medulla activity

function of pons

• contain nuclei for several cranial nerves

• responsible for information relay, cranial nerves, and unconscious control

functions of the cerebellum.

associated with motor and coordination, as well as attention shifting & between auditory/visual stimuli and rhythm recgonition

what is the thalamus?

-a pair of structures in the center of the fporebrain.

• sensory info. goes first to the thalamus, which then processes it and sends output to the cerebral cortex.

hypothalamus

• small area near base of the brain, ventral to the thalamus.

• contains a # of distinct nuclei, which are associated with motivation & emotion

  • feeding, drinking, sexual behaviors, etc.

hippocampus

critical for certain types of memories, especially about individual events

3 main structures of the Basal Ganglia.

1. caudate nucleus

2. putamen

3. globus pallidus

Integrates motivational and emotional behavior to increase the vigor of selected actions.

• critical in movements, skills, habits, & other learning

the ventricles

central canal—tube surrounding a fluid canal, persists into adulthood

ventricles—fluid-filled cavities in the brain

lateral ventricle—ventricles in each hemisphere

third ventricle—in posterior part of brain

fourth ventricle—center of medulla

what are menengies?

membranes surrounding the brain and spinal cord; from here, fluid goes to the subarachnoid space

corpus collosum

neurons in each hemisphere communicate with neurons in the corresponding part of the hemisphere through 2 bundles of axons that make up the corpus callosum

anterior commissure

communicates wth neurons and connects structures such as the amygdala ad temporal lobe with the rest of the 2 cerebral hemispheres

occipital lobe

primary visual cortex or striate cortex

parietal lobe

primary somatosensory cortex

• receives sensations from touch receptors, muscle stretch receptors, & joint receptors

• includes 4 bands of cells parallel to central sulcus

temporal lobe

primary auditory cortex

-left lobe: understanding spoken language

-right lobe: understanding non-verbal information

• contributes to complex aspects of vision, perception of movement, and recognition of faces

frontal lobe

• primary cortex and prefrontal cortex, pre-central gyrus

  • specialized control of fine movements, such as moving 1 finger at a time

prefrontal cortex

• important for decision-making & planning movements

• working memory—ability to remember recent events

• delayed-response task—people hear//see something and respond after a delay

ablation v.s. lesions

ablation—removal of a brain area

lesions—damage to a brain region; used to study structures hard to study with ablation

transcranial magnetic stimulation (TMS)

• allows researchers to do behavior\al studies with some areas active and some inactive.

• applies magnatic stimulation to a portion of the scalp

• produces vital lesions that outlasts the stimulation itself

Electroencephalography (EEG)

Electrodes measure electrical activity in the =brain at any moment of the population of the cells under the electrode

measures activity in response to a stimulus

Positron-emission tomography (PET)

provides high-resolution image activity in a living brain by recording the emission of radioactivity from injected chemicals

Functional Magnetic Resonance imaging (fMRI)

Blood Oxygenation Level-Dependent (BOLD) signal

• highly sensitive magnets detect the difference between oxygenated and deoxygenated blood

Computerized Axial Tomography (CAT/CT)

used to identify tumors and abnormalities

Injected dye into the blood allows increased contrast in the image and passes X-rays through the head