UNIT 2 AP PSYCH - Biological Basis of Behaviour

Hemispheres

• Halves of brain

• Right is left and left is right

• They always coordinate with each other

• The corpus callosum communicates

Corpus callosum

• Bundle of nerves that communicate between the two hemispheres

LEFT and RIGHT hemisphere

LEFT

• language, speech, handwriting, rhythm

• Analytical side of the brain

• control the right side of the body

RIGHT

• widespread perception, visuals, patterns, facial recognition

• processing and creativity

• Controls the left side of the body

Lobes

Areas of the cerebral cortex with a SPECIFIC FUNCTION

Frontal Lobes

Reasoning, motor skills, cognition, expressive language

Prefrontal Cortex

complex cognitive behaviour, personality, decision-making, social behaviour

Motor Cortex

Receives information from various from various lobes of the brain and carries out body movement

Broca’s Area

Speech production and language comprehension (speech muscle movements)

Parietal Lobes

• Process sensory signals

  • Touch, pressure, sensitivity, pain

Somatosensory cortex

• Receives and processes sensory information from the whole body

Occipital Lobes

• Contains visual centers of the brain

Visual Association Cortex

Recognizes lines, angles, shapes, shadows, and movement

Temporal lobe

Neurons that help with sensible learning and meaningful speech

Wernicke’s area

• Responsible for speech comprehension

  • Plans movements for Broca’s

Brainstem

• Most primitive part of the brain

  • base connected to spinal cord

• Controls message flow from brain —> body

• Breathing, swallowing, ❤ rate, blood pressure, conciousness, sleepiness

Pons

Bridges MEDULLA and CEREBELLUM, breathing and sleep cycle control

The Reticular Formation

• Integrated Nervous system

• Nerve network carrying messages from brainstem

  • pain intensity and body part regulation

  • filters unnecessary stimulus

Cerebellum

• Little brain

• posture, balance, coordination of voluntary movements

• Allows muscles to act together and produce fluid movement

Thalamus

• Processes and transmits movement and sensory information

• Relay station to the cerebral cortex

• Receives all sensory input

Limbic system

• Emotions

• Hunger and sex drive

• Episodic memory formation

Hypothalamus

• Connects with other regions

• Hunger, thirst, emotions, body temp, circadian rhythms

  • Controls pituitary by secreting hormones

Hippocampus

Formation, organization, and storage of certain memories, connects certain sensations and emotions to memory

Amygdala

• “Fear center” of the brain

• processes emotion and survival responses '

• Activated during potentially harmful situations

• Aggression and fear

Neuroscience

• Study of the brain, brain science

• Works together with other disciplines

• Looks at the brain and models the brain using multiple tools

Brain Autopsy

• Examination of the brain tissue after death

• Currently the only way to diagnose specific degenerative disorders

  • Remaining family members can often be cured after autopsy

Lesioning Studies

• Humans with brain lesions can help us understand what specific parts of the brain do

  • Can also be done on LAB RATS

Prefrontal Lobotomy

• Removes part of the brain (prefrontal cortex) to change and control behaviour

• Unattaches cortex from the rest of the brain

Hemispherectomy

• Removes half of the brain to control seizures

Deep brain stimulations

• A newer way to change and assess psychological issues

• Less invasive

• Electrodes placed on specific parts of the brain to stimulate it

Transcranial Magnetic Stimulation (TMS)

• Uses magnetic want to alter brain’s electric fields

  • Helps change moods and cures depression

Brain Scanning

• Provides information about brain structure and anatomy

X-Rays

• Shows hard structures

  • Bones and cartilage

  • Helps find fractures

  • NOT a complete evaluation

Electroencephalograph

• Measures brain activity through electrical wave pulses

  • Electrodes placed on scalp

  • Electric output forms waves that indicate sleep, seizures, etc.

  • Used in laboratories usually to measure experimental patient brain activities

  • Records patterns on the brain’s SURFACE

    • What areas are active when

Computer tomography

• 2D x-ray photos that are identified from all kinds of angles to put together a 3D photograph of the organ, tissue, or area

  • Clots, Muscles, Etc.

  • Large scale brain features

  • Used in ERs to quickly identify issues

Functioning MRS (MRI)

• Detects changes in blood oxygenation which responds

  • More oxygens more activity

  • Activity and high resolution images

Positron Emission Tomography

• Glucose is on energy source, decay emits positrons

• Measures brain activity

• Positron picked up by the detectors

Neuroplasticity

• Brain can be damage resistant

• The ability to structure and function of cells in the brain as a trauma response

• This lessens as you age

Functional Plasticity

• Brain moves functions from a damaged part of the brain to undamaged

Structural plasticity

• Brain physically changes structure when learning new things

Split Brain

• Corpus callosum in insufficient in communication between right and left hemispheres of the brain

The Nervous System

• Body’s communication network that consists of all nerve cells

  • The body’s electrical wiring

• Allows organisms to sense, organize, and react to environmental information

Central Nervous system

• Coordinates the actions and interactions of the BRAIN and SPINAL CORD

  • Body’s main control center

  • Largest part of the nervous system

  • Spinal chord is an informational highway connecting the PNS to the brain

Peripheral nervous system

• includes the sensory nerves outside the brain and spinal chord that connect the central nervous system (CNS) to the rest of the body

  • PNS connects the CNS to organs, limbs, and skin

Motor Pathway

• Part of the PNS

• Signals from brain to muscles/glands

Sensory pathway

• part of the PNS

• signals from sensory receptors to the brain

Somatic nervous system

• part of a motor pathway

  • The nerves that transmit signals from your brain to skeletal muscles to allow voluntary movement

  • responsible for carrying sensory and motor information to and from the CNS

Sensory neurons (afferent neurons)

• Carry information from nerves to the CNS

• These sensory neurons allow us to take in sensory information and send it to the brain and spinal cord

Motor neurons (efferent neurons)

• Carry information from brain and spinal cord to muscle fibers throughout the body

• These motor neurons allow us to ttake physical action in response to stimuli in the environment

Interneurons

• Neurons within the brain and the spinal cord that communicate internally and intervene between sensory inputs and motor outputs

Reflex Arc

• Takes place ONLY IN THE SPINAL CORD (reflexes don’t move to the brain, stay only in the spinal cord)

• signals sent from sensory organ to the spinal cord which processes information instead of passing onto the brain

Autonomic nervous system

• regulated involuntary and unconscious actions

  • breathing, blood pumping through veins, digestion, heartbeat, work of internal organs

  • Done UNCONSCIOUSLY

Sympathetic nervous system

• Part of your autonomic nervous system

• Emergency response system if something alarms, alerts, or enrages you

  • Fight, fight, or freeze response

  • Accelerates your heartbeat, raises your blood pressure, slows your digestion, cools you with perspiration, makes you alert and ready for action

parasympathetic nervous system

• functions to cal the person

  • rest and digest

• reduces body arousal, energy, decreases blood sugar, increases blood flow to the digestive organs, decreased heart rate

Neurons

• A specialized cell in the nervous system that receives and sends messages with electrochemical signals

1. Chemicals stimulate the neuron

2. The neuron creates electricity

3. The neuron releases chemicals

Glial cells

• Cells that provide physical support for neurons to grow

  • make up around 90% of he brain (50;1)

• surround and transfer nutrients to neurons, clean up neuron remains, and provide insulation

Dendrites (antenna)

• part of the neuron

  • Branch like extension that receives electrical messages from other cells

Soma (life support)

• cell body of the neuron responsible for maintaining the cell and keeping the neuron, including the nucleus, functional

Axon (talker)

• fibers that extend from the cell body to the terminal endings, help carry messages to other cells

Myelin sheath

• fatty substance produced by glial cells that wrap around axons to protect the nerve fiber from damage

• insulates the cell and speeds up neural messaging

Axon terminals

• tips at the end of the axon

  • send signals to other neurons

  • AKA terminal buttons OR synaptic knobs

synapse

• gap between the terminal button and the next neuron

• where axons connect

Synaptic vesicles

• store neurotransmitting chemicals that are released at the synapse

synaptic cleft or gap

• Under a MILLIONTH of an inch wide

recept sites

• receive signals

  • the “lock” that neurotransmitting molecules fit into