Chapter 3 Psychology

Neuroscience

Neuroscience

• study of the brain and nervous system

How scientists study the nervous system

• examine autopsy tissue

• test behavior of patients with brain damage

• record electrical brain activity (EEG or ERP)

• animal studies

• neuroimaging techniques that show visual images in awake humans

Chronic Traumatic Encephalopathy

• associated with a constellation of neurocognitive symptoms, personality change memory loss, progressive dementia, mood swings, confusion, tremors, speech and gait abnormalities, depression

Neuron

a nerve cell

Sensory

• gathers sensory information

Motor

• communicates information to the muscles

Interneuron

• carries information between neurons in the brain and spinal cord

Glia

cells that help support nerurons

Astrocytes

• makes blood brain barrier

• influences communication between neurons

• helps heal brain damage

Oligodendroglia

• provides myelin to speed up transmission of neurons

Microglia

• cleans up dead cells

• prevents infection in the brain

resting potential

• when a neuron is at rest and it is negatively charged inside (intracellular) opposed to outside (extracellular)

Action Potential

• neuron fires pores in the neuron/ion channels open to let charged ions move in and out of neuron

• neuron becomes more positive inside relative to outside

• shift in electrical charge triggers axon terminals to release neurotransmitters

All or None Principal

• a neuron is either stimulated enough to start an action potential or it is not

• immediately after a neuron has fired it cannot fire again (refractory period)

Nodes of Ranvier

• regions of bare axons between areas wrapped in myeline

• action potentials travel down myelinated axons by jumping node to node

Communication Between Neurons

• action potential triggers release of neurotransmitters into the synapse(space between neurons)

• chemical neurotransmitters taken up by the neurotransmitter receptors in a neighboring neuron

Neurotransmitter Receptors

Postsynaptic Receptors

• electrical events in postsynaptic neurons that occur when a neurotransmitter binds to one of its receptors

• when receptor is activated positive or negative ions can flow through the receptor into the neuron

Excitatory Postsynaptic Potentials (EPSPs)

• depolarize the neuron and increase the likelihood of an action potential

Inhibitory Postsynaptic Potentials (IPSPs)

• hyperpolarize the neuron and decrease the likelihood of an action potential

stem cells

• divides and produces different types of neurons depending on their environment

Neuroplasticity

• brains ability to make new neural connections or to reorganize in response to injury or changes in the environment

Types of Neurons

Afferent Neurons

• carry signals from the PNS to the CNS

Efferent Neurons

• carry signals from the CNS to the PNS

• muscles and glands

Interneurons

• relay cells between different neuron types

Hindbrain

• pons

  • important for sleep

• reticular formation

  • regulates sleep/wake

• cerebellum

  • motor coordination

• medulla

  • heartbeat, breathing etc

Midbrain/forebrain

• thalamus

  • relay sensory information

• hypothalamus

  • motivation/drive

• hippocampus

• substantia nigra

  • nucleus dopamine send axons to forebrain

  • parkisons disease if damaged

• pituitary gland

  • hormones

Neocortex

• sensory cortex

  • registers sensory neurons

• motor

  • registers motor neurons

• association cortex

  • complex functions

limbic system

• amygdala

  • fear

• hippocampus

  • learning and memory

Cerebral cortex

• frontal lobe

  • intellectual thinking

• prefrontal cortex

  • memory, morality, mood, planning

• parietal lobe

  • sensory integration

• occipital lobe

  • vision

• temporal lobe

  • recognizing faces

Parallel processing

• communication between brain lobes performing tasks simultaneously (air traffic controllers)

Brocas area (frontal lobe)

• speech production

Wernickes area (temporal lobe)

• language comprehension

Corpus Callosum

• connects the 2 brain hemispheres

homologous traits

• traits similar between species tracing back to common ancestor

Analogous traits

• characteristics evolving independently in different species

Convergent evolution

• development of similar physical traits in different species not sharing common ancestor