Biology, Behavior, and Mind

• Recent biological discoveries of the mind

  • According to biology, the body is made up of cells -> nerve cells - that conduct electricity and communicate with the brain by sending messages across a gap that separates them.

  • There are multiple brain systems that all serve specific functions

  • Humans use info processed in these diffs brain systems to make the experience of sights/sounds/meanings/memories/pain/passion

  • Our ADAPTIVE  brain is wired by our experiences

• We are BIOPHYSICAL systems -> body systems -> individual -> communities, and families

Neural Communication

• Neuron: a nerve cell consisting of the cell body and branching fibers

• Dendrites: neurons bushy, branching extensions that receive messages and conduct impulses toward the cell body

• Axon: neuron extension that passes messages through its branches to the other neurons or muscles or glands

• Myelin Sheath:  fatty tissue layer segmentally encasing the axons of some neurons - > enables greater transmission speed as neutral impulses hop from one node to the other

  • Laid down until 25y/o ->> if degenerates it can lead to multiple sclerosis

• Action Potential: a neutral impulse - a brief electrical charge that travels down an axon

• Resting Potential- positive-outside/ negative-inside state of an axon

• Refractory period - a resting pause, a period of inactivity after a neuron has fried

• Neuron signals can be like an accelerator or brake

• Threshold: The level of stimulation required to trigger an action

• All-or-none response: a neurons reaction of either finning

How Neurons Communicate

• Synapse: the junction between the axon tip of the sending neuron and the dendrite/cell of the body receiving neuron -> Sir Charles Shemington (1857-1952)  noticed a neutral impulse interruption in the transmission

  • The gap at this junction is called the synaptic gap/synaptic cleft A.K.A the  meeting point between neurons

• Neurotransmitters: chemical messengers that cross the synaptic gaps -> when released by sending neuro they travel across the synapse and bind receptor sites on the receiving neuron -> influence whether that neuron will generate a neural impulse

• Reuptake: neurotransmitter reabsorption by the missing neuron (reabsorbs excess neurotransmitters

How Neurotransmitters Influence Us

• Particular brain Pathways may only use one or two neurotransmitters or particular neutrons.  this may affect specific behaviors and emotions.

• Neurotransmitter systems do not operate in isolation they interact effects Berry with receptions they stimulate

  • ACH is released to muscle cell receptors therefore muscle contracts

  • ACH  transmission locked there for muscle cannot move

• Endorphins:  morphine within natural opiate-like neutrons.  link to pain control and pleasure this explains runner's high pain-killing effects of acupuncture indifference to pain and severely injured people

How Drugs & Other Chemicals After Neurotransmission

• When flooded with opiate drugs the brain may stop producing natural opiates when the drug is withdrawn the brand may not produce other opiates.

• Agonist:  a molecule that by binding to receptor site stimulates a response this response may be similar to a new row transmission to bind to its receptors and mimic its effects

  • Some opiate drugs are agonists  and produced temporary highs by amplifying normal sensations of  arousal or pleasure

The Nervous System

• nervous system:  the body's electrochemical communication Network consisting of all the nerve cells of the peripheral and central nervous system.

• central nervous system:  the brain and spinal cord bodies decision-makers

• peripheral nervous system:  the sensory and movement neurons that connect the central nervous system to the rest of the body this is also responsible for Gathering info for transmitting CNS decisions to other body parts

• Nerves:  bundled axons that form neutral electrical cables connecting the CNS with muscles or glands sense organs.

• Sensory neurons:  neurons that carry incoming info from the sensory receptors to the brain and spinal cord for processing;

• Motor neurons:  neurons that carry outgoing information from the brain or spinal cord to the muscles and glands

• Our nervous system has a few million Sensory neurons or motor neurons and billions of meterneurons

The Peripheral Nervous System

• Somatic nervous system:  the division of the PNS that controls the body skeletal muscles

• Automatic nervous system:  part of the PNS that controls the glands and muscles of the internal organs sympathetic division arouses parasympathetic division columns

• Sympathetic Nervous System:  division of the ANS that arouses the body and mobilizes its energy in stressful situations

• Parasympathetic nervous system:  division of the ANS that columns the body and conserves its energy

The Endocrine System

• Endocrine system:  the body's slow chemical communication system it holds a set of glands that secrete hormones into the bloodstream

• Hormones:  chemical Messengers that are manufactured by the endocrine glands that travel through the bloodstream and affect other tissues

  • Some are chemically identical to neurotransmitters but take longer to reach the designated tissue and tend to last longer than the effects of neutral messages

• Adrenal glands:  pair of endocrine glands that sit above the kidneys and secrete epinephrine/norepinephrine This helps arouse the body in times of stress.

• Pituitary glands: Endocrine system most influential gland under the influence of the hypothalamus controls growth and other endocrine glands

• Feedback system of the brain->  pituitary-> are there glands-> hormones-> body and brain

The Tools of Discovery: Having our Head Examined

• Lesion:  tissue destruction brain lesions are naturally / experimental he caused destruction of brain tissue

• Electroencephalogram: An amplified recording of the waves of electrical activity sweeping across the brain's surface this is measured by electrodes placed on the scalp

• CT scan:  series of X-ray photographs taken from different angles and combined by a computer for composite representation of a slice of the brain structure also known as a CAT SCAN

• PET scan:  visual display of brain activity that detects where a radioactive form of glucose closed while the brain performs a given task

• MRI:  Techni using magnetic fields  and radio waves to produce computer-generated images of soft tissue to show the brain's Anatomy

• fMRI:  technique for revealing blood flow and therefore brain activity by comparing successful MRI scans this also shows brain function and the Brain structure

Older Brain Structures

• The cerebral cortex made up of neurons and glial cells is divided into the right and left hemispheres and into four lobes.

• The frontal lobe is primarily responsible for thinking, planning, memory, and judgment.

• The parietal lobe is primarily responsible for bodily sensations and touch.

• The temporal lobe is primarily responsible for hearing and language.

• The occipital lobe is primarily responsible for vision.

• The motor cortex controls voluntary movements.

• The sensory cortex receives and processes bodily sensations.

• The left cerebral hemisphere is primarily responsible for language and speech in most people

• The right hemisphere specializes in spatial and perceptual skills, visualization, and the recognition of patterns, faces, and melodies.

Genes: Our Code for Life

• Behavior genetics: the study of the relative power and limits of genetic and environmental influences on Behavior

• Environment:  every external influence from creating natural nutrition to the people and things around us

• Chromosomes:  thread-like structures made of DNA molecules entertaining the genes

• DNA: A complex molecule containing the genetic info making up chromosomes

• Genes:  the biochemical units of Heritage see that makeup chromosomes segments of DNA are capable of synthesizing proteins

• Genome:  the complete instructions for making an organism consisting of all the genetic material in that organism’s chromosomes

Twin and Adoption Studies

• Identical Twins: Twins who develop from a single fertilized egg that splits into two creating two genetically identical organisms they have to be the same sex

• Fraternal Twins:  twins develop from separate fertilized eggs and are  genetically no closer Ben Brothers/sisters but share a fetal environment same or different sex

• Adoptees are more similar to their biological parents than their adoptive ones their environment and shared by families children's has virtually no discernible impact on their personalities

The New Frontier Molecular Genetics

• Molecular Genetics: The subfield of biology that studies the molecular structure and functions of genes

  • a goal of molecular Behavior genetics is to find some of the many genes that orchestrate traits such as body weight sexual orientation and extraverts

Heritability

• Heritability:  the proportion of variation among individuals that we can attribute to Gene's heritability of a trait may vary depending on the range of populations and environment study

  • If the heritability of a trait is for example 50% it means genetic influence explains 50% of The observed variation among people we can never say how much of an individual's personality/intelligence is inherited

• Gene-Environment Interaction

• Genes and environment - nature & nurture  work together genes are self-regulatory

• Interaction is the interplay that occurs when the effects of 1 Factor such as environment depends on another Factor such as heredity

• Epigenetics is the study of environmental influences in gene expression that occur without a DNA change

Splitting the Brain

• Corpus callosum:  the large band of neural  fibers connecting the two brain hemispheres and carrying messages between them

• Split-brain:  a condition resulting from surgery that isolates the brain 2 hemispheres by cutting the fibers connecting them

Right Left Differences in the Intact Brain

• The left side of the brain signed and spoken language are the same

• all the left hemisphere is adept at making quick and internal interpretations of language the right hemisphere

  • excels in making inferences - more quickly left recognizes Solutions

  • helps modulate our speech to make meaning clear

  • helps us orchestrate our sense of self

The Biology of Consciousness

• Consciousness:  our awareness of ourselves and our environment this helps in the long-term interests and promotes our Survival by anticipating how we seem to others and helping us read their emotions

Cognitive Neuroscience

• Cognitive neuroscience:  the interdisciplinary study of the brain activity linked with cognition which means thinking perception memory and language

• how synchronized activity produces awareness is a mystery and based on artificial activation patterns scientists can ‘read’ your mind

Dual Processing the Two-Track Mind

• dual processing:  the principle that information is often simultaneously processed on separate conscious and unconscious tracks

• The dual processing system of vision

  • visual perception track:  enables us to think about the world recognize things and plan future actions

  • visual action track guides are moment-to-moment movements

• Harlow Face Illusion:  conflicts with the Dual processing system of vision because the unconscious mind knows the truth of the illusion

• in everyday life, we mostly function like it an automatic pointed short camera with  manual also known as the conscious override

Functions of the Cortex

• Motor cortex: Area of the rear of the frontal lobe that controls voluntary movement

  • The stimulation caused movement only where the motor cortex was located

  • The stimulation parts of the motor cortex in the left/right hemisphere caused movement of the opposite side of the body

Sensory Functions

• Somatosensory cortex:  area at the front of the parietal lobes that registers and processes body tumors and movement sensation

  • The more sensitive the body's region the larger the somatosensory cortex devoted to it

• Visual cortex:  located in occipital lobes processes visual information

• Auditory cortex:  located and temporal lobes process auditory units

Association Areas

• Association areas:  areas of the cortex that are not involved in primary motor or sensory functions

  • Prefrontal cortex:  located in the forward part of frontal lobes please enable judgment planning processing at new memories

• frontal lobe damage can alter personality and remove a person's in divisions moral compass may seem unrestrained

The Brains Plasticity

• Plasticity; the brain’s ability to change Especially during childhood by reorganizing after damage or by building new Pathways based on experiences

• Facts related to brain damage

  • severed neurons I'd like cut skin cannot regenerate

  • cell membrane function seemed pretty assigned to specific areas

  • some of the brain's neural tissue can reorganize in response to damage