Biopsychology Exam #2

What are the divisions of the Peripheral Nervous System?

Somatic Nervous System and Autonomic Nervous System

Somatic Nervous System…

• Carries sensory info TO the CNS.

• Carries motor info FROM the CNS.

The Somatic Nervous System is…

Voluntary.

Dorsal (inferior)

Towards the stomach or the bottom of the head

Ventral (inferior)

Toward the stomach or bottom of the head

Anterior (Rosstral)

Towards the nose (front of the head)

Posterior (Caudal)

Towards the tail (back of the head)

Medial

Towards the center or away from the side.

Lateral

Towards the side, away from the midline

Radiologist Convention

Left of the patient is right.

Neurologist Convention

Left of the patient is left.

Unilateral

Found on one side of the body; left-lateralized, right lateralized.

Bilateral

Found on both sides of the body

Ipsilateral

On the same side of the body

Contralateral

One on the opposite side of the boyd

Meninges has how many layers?

3 layers

Outermost layer of Meninges?

Dura Mater

Middle layer of Meninges?

Arachnoid membrane

Innermost layer

Pia Mater

Cerebrospinal fluid (CSE)…

Cushions the brain and provides nutrients.

Blood-brain barrier

Tightly packed cells of blood vessel walls, prevents entry of many molecules

Gray matter

Composed of largely cell bodies (unmyelinated interneurons)

White matter

COmposed of largely myelinated axons and nerve fibers.

Cerebral Commissures

Fiber bundles that conncect the two cerebral hemispheres

Sulci (Sulcus)

Shallow grooves

Gyri (Gyrus)

Elevations between the grooves

Lateral Fissure/Central Sulcus

Major landmarks that divide the lobes.

Frontal Lobe is responsible for…

Movement, decision making, control, planning

Parietal Lobe is responsible for…

Sense of touch, attention control, and visual-spatial

Temporal Lobe

Memory, Language, Emotion

Occipital Lobe

Visual Perception

Sensory System organization - Hierarchical

From lower-order to higher-order information processing

Sensory system organization - Information flow

Bottom to Up

Parallel Processing

Process multiple different dimensions of the same infro through different neural pathways.

Dorsal Stream

“Where?” pathways

Ventral Stream

“What?” pathway

Visual information is shown…

Through two distinct neural pathways.

Damage to receptors

Unable to detect sensory stimuli

Damage to cortex

Basic sensory detection preserved, difficulty with more complex analysis

Vision in the brain

Occipital Lobe

Auditory in the brain

Temporal Lobe

Somatosensory (touch, pain) in the brain

Parietal lobe

Smell (Olfaction) in the brain

Olfactory Complex

Taste (Gustation) in the brain

Gustatory Cortex

Vestibular (balance)

Brain stem/cerebellum

Receptive field

Area of sensory space that can active neuronal responses when the neuron is stimulated.

Size and Distribution of a Receptive field...

Varies

Receptive fields often have…

Excitatory and inhibitory areas.

Lateral Inhibition for detecting stimuli in sensory system

Activated cells that are capable of inhibiting their neighbors

Sensory Systems show adaptation by…

Changing their sensitivity to a stimulus upon constant stimulation

Topographic maps

Sensory system is projected onto the sensory surface of the brain.

Sensory system columns

Perpendicular to brain surface, cells in same column have similar function

Sensation

Ability of the body to detetct external stimuli

Transductions

Receptors converting external stimuli to neuronal activity

Reception and Transduction

Sensory events (physical energy) are converted to neural signals by receptors and are represented by patterns of nerual activity in the brain.

“Patterns” are based on…(how strong is it?)

Stimulus intensity

“Patterns” are based on…(What is it?)

Stimulus modality

“Patterns are based on…(Where is it?)

Stimulus location

Perception

The higher-order process of integrating, recognizing, and interpreting sensation.

Autonomic nervous system

Controls internal involuntary body functions (Heart rate, blood pressure, etc)

Sympathetic

Aroused body

Parasympathetic

Relaxes body