AP Psych

Central Nervous System (CNS)

comprised of brain and spinal chord

Peripheral Nervous System (PNS)

comprises all nerves in the body (excluding those in brain and spinal chord)

can be subdivided into somatic and autonomic nervous systems

Central Nervous System (CNS)

comprised of brain and spinal chord

Peripheral Nervous System (PNS)

comprises all nerves in the body (excluding those in brain and spinal chord)

can be subdivided into somatic and autonomic nervous systems

Somatic nervous systems

responsible for voluntary movement of large skeletal muscles

Autonomic nervous system

control nonskeletal or smooth muscles (like heart and digestive track)

can be divided into sympathetic and parasympathetic nervous systems

Sympathetic nervous system

Associated with processes that burn energy. Heightened state of psychological arousal (e.g. fight-or-flight response)

Reactions of sympathetic nervous system

• increased heart reate

• increased respiration rate

• decrease in digestion

• decrease in salivation

• blood transfer to skeletal muscles

Parasympathetic nervous system

complementary system responsible for conserving energy

Reactions of parasympathetic nervous system

• digestion continues

• decreased heart rate

• decreased breathing rate

(body returns to homeostasis)

Hindbrain

Oldest part of the brain to develop (evolutionary terms)

components of the hindbrain

• cerebellum

• medulla oblongata

• reticular activating system (RAS)

• pons

Cerebellum

controls muscle tone and balance

Medulla oblongata

Control involuntary actions; basic life functions (e.g. breathing, heart rate, digestion, swallowing)

Reticular activating system (RAS)

controls arousal (a.k.a. reticular formation)

Arousal

wakefulness and alertness

Pons

(latin for bridge) way station, passes neural information from one brain region to another

Components of midbrain

• Colliculus (superior and inferior colliculi)

• tectum

• tegmentum

Midbrain

the topmost part of the brainstem, the connection central between the brain and the spinal cord

Superior colliculi

(a.k.a. optic tectum) control head, neck, and eye movements

Midbrain functions

involved in several functions, including motor control (particularly eye movements) and processing of vision and hearing

Inferior colliculi

main part of the midbrain's auditory pathway. Help with sound localization, startle responses, and discriminating pitch and rhythm

Tegmentum

region in the brainstem that controls movement coordination, sensory processing, and alertness (arousal)

Forebrain

brain structure responsible for higher-order mental processes such as memory and decision-making

Components of forebrain

• limbic system

• cerebral cortex

Limbic system

emotional center of brain

Components of limbic system

• Thalamus

• Hippocampus

• Amygdala

• Hypothalamus

Cerebral cortex

involved in higher cognitive functions (thinking, planning, language use, fine motor control)

Sensory cortex

Area of cerebral cortex that receives sensory input

Motor cortex

Area of cerebral cortex that sends out motor information

Corpus callosum

band of connective nerve fibers that join left and right cerebral hemispheres

Left hemisphere

typically specialized for language processing

Broca’s area

in charge of speaking ability

Expressive aphasia

loss of the ability to speak

Wernicke’s area

in charge of comprehending speech

Receptive aphasia

inability to comprehend speech

Right hemisphere

processes visual and spatial information

where right visual field is processed

left, more verbal side of brain

where left visual field is processed

right, more visual side of brain

Contralateral processing

ability of (non-split) brains to use both hemispheres and integrate information between them via corpus callosum

Components of cortex

• 4 lobes:

• frontal lobe

• parietal lobe

• temporal lobe

• occipital lobe

• association areas

Frontal lobe

responsible for higher-level thought and reasoning (e.g. accessing working memory, attention, problem solving, planning, performing movement)

Parietal lobe

handles somatosensory information & home of somatosensory cortex (receives info about temp, pressure, texture, and pain)

Temporal lobe

handles auditory input (critical for processing speech and appreciating music)

Occipital lobe

processes visual input (this input crosses optic chasm)

Optic chiasm

part of the brain where the optic nerves from each eye cross over

Association areas

responsible for associating information in the sensory and motor cortices

Dysfunctions due to damage to association areas

• apraxia

• agnosia

• alexia

• agraphia

Apraxia

inability to organize movement

agnosia

difficulty processing sensory input

Alexia

inability to read

Agraphia

inability to write

Nerves

bundles of neurons, basic unit of nervous system. Cells with clearly defined soma

Soma

nucleated cell body

Dendrites

receivers of input from other neurons (through receptors on surface) that branch out from soma

Axon

long, tubelike structure that responds to input from dendrites and some