Ch. 3 20140201
Synaesthesia: crosssensory experience
This chapter is about psychological activities at the genetic and neurochemical levels, and the functions of
various brain regions; on drugs and certain genetics
Genetic Basis of Psychological Science
Genetic factors and environmental factors shape up who we are
“Genetics” refers to the process involved in turning genes on and off; it reveals how environmental
factors affect our genes, thoughts, behaviours and feelings
Genome: an organism’s compete set of DNA, including its genes. It provides detailed instructions for
everything; everything is determined by which genes are turned on or off within the cell.
Genome provides the option, and the environment determines which option is taken
Chromosomes: structures made of genes; Human has 23 pairs of them with half of each pair coming
from each parent
Genes are components of DNA (deoxyribonucleic acid)
DNA: substance that consists of two intertwined stands of molecules. The sequence of molecules
specifies an instruction to manufacture a distinct protein.
Protein: the basic chemicals that make up the structure of cells and direct their activities
Gene: a segment of DNA, is involved in producing a protein that carries out a specific task; the
environment then determines which protein are produced and when are they produced
Gene expression causes cells become specialized; it determines the body’s basic physical makeup and
also specific developments
What Are the Basic Brain Structures and their functions? 108 The nervous system is divided into two units:
Central Nervous System (CNS)
Peripheral Nervous System (PNS)
CNS consists of the spinal cord and brain
PNS consists of all the other nerve cells in the body
PNS transmits a variety of information to the CNS, which organizes and evaluates that information and
directs PNS to perform specific actions or make adjustments
Early in life, overabundant connections form among the brain’s neurons, then life experiences help dry
out some of these connections to strengthen what is left.
The Brain: Understanding its functions
Case: Phineas Gage
The accident has caused major personality changes; his intellectual faculties and animal propensities
have been destroyed. After a decade, his health has declined and he died within a few months.
Conclusion: Gage’s psychological impairments had been severe and that some areas of the brain
have specific functions that could not been taken over by the other parts
Prefrontal cortex: the part that is responsible for personality and selfcontrol; it is concerned with social
The ancient Egyptians believe the heart determines the afterlife; the Greeks and Romans then
recognized the brain for normal mental functioning
Phrenology: the practice of assessing personality traits and mental abilities by measuring bumps on
human skull (Franz Gall)
Karl Lashley: specific brain regions are involved in motor control and sensory experiences; but all other
parts contributed equally to mental abilities.
Broca’s area: left frontal region; it is important of speech and crucial for the production of languages
The Brain: Hindbrain: Spinal cord: a rope of neural tissue that runs inside the hollows of the vertebrate from above
the pelvis to the base of the skull.
coordinates each reflex;
carries signals from the brain to the body parts below
the cord is composed of two distinct tissue: the grey matter: dominated by neurons’ cell bodies, and
the white matter, which consists of mostly of axons (nerve fibre) and the fatty sheaths that surround
Brainstem: the base of the skull;
consists: Medulla Oblongata, the pons, and the midbrain
it houses the nerves that control the most basic functions of survival
many reflexes emerges from here
consists of network of neurons reticular formation which project up into the cerebral cortex (outer
portion of the brain) and affect general alertness. / sleep
Cerebellum: large protuberance connected to the back of the brain stem
important for motor function (muscle activities)
damage of the bottom causes head tilt, balance problems, and a loss of smooth compensation of eye
position for head movements
damage to the ridge would affect your walking
damage to the bulging lobes would cause a loss of limb coordination
important for motor learning; maybe empathy Forebrain: above the brain stem; consists of two cerebral hemispheres; left and right; The outside is the
cerebral cortex; below are the subcortical regions, some of them belong to the limbic system, the
border that separates the evolutionary older and newer parts they include:
Hypothalamus: the brain’s master regulatory structure that is vital for temperature regulation. Emotion,
sexual behaviour, and motivation. It receives inputs from everywhere and projects influence back to
everywhere. E.g. body temperature, blood pressure, glucose levels, thirst, hunger and basic drives.
Thalamus: the gateway to the cortex; it receives most incoming sensory information before it reaches
the cortex except the sense of smell. It shuts the gate on incoming sensation while the brain rests
Hippocampus: a brain structure important for the formation of new memory; it creates
interconnections within the cerebral cortex with each new experience; might be responsible for how we
remember arrangements of both places and space
Amygdala: a brain structure that serves a vital role in our learning to associate things with emotional
responses and in processing emotional information; connect memories of things to the emotions
engendered by those things. It is in front of the hippocampus. It has a special role in our responding to
stimuli elicit fear and evaluating a facial expression.
The Basal Ganglia: a system of subcortical structures that are important for the initiation of planned
movement. Damage of it can impair the learning of movements and of habits. One structure called the
nucleus accumbens is important for experiencing pleasures and rewards; it activates dopamine
neurons. The Cerebral Cortex: Complex Mental Activity
The outer layer of brain tissue, which forms the convoluted and twisted surface of the brain.
The site of all thoughts, detailed perceptions, and consciousness; the source of culture and
It has four lobes: frontal, parietal, temporal and Occipital (lobe)
Corpus Callosum: the massive bridge of millions of axon, connect the hemisphere and allows
information to flow between them
Occipital Lobes: regions of the cerebral cortex, at the back of the brain; important for vision; visual
images of colours, forms and motions.
Parietal Lobes: regions of the cerebral cortex, in front/on top of the occipital lobes and behind the
frontal lobes, important of the sense of touch and the spatial layout of an environment; with opposite
direction of the transmission of information. The information is represented along the primary
Temporal lobes: the lower region of the cerebral cortex, important for processing auditory information
and for memory. It is where the fusiform face area is which becomes active when people look at faces.
Frontal lobes: the region at the front of the cerebral cortex concerned with planning and movement. It
consists of premotor cortex (neurons that project to the spinal cord to move the body’s muscles) and
the primary motor cortex. The rest consists of the prefrontal cortex: a region of the frontal lobes,
prominent in humans, important for attention working memory, decision making appropriate social
behaviour and personality, which occupies 30% percent of the brain.
Lobotomy: damaging the prefrontal cortex to treat mental patients, it leaves patients emotionally flat
and easier to manage. But this also leaves them disconnected from their social surroundings.
How are Neural Messages Integrated into Communication Systems?
PNS: transmit a variety of information to the CNS and responds to messages from the CNS to perform
specific behaviours or make body adjustments
The PNS: consists of the Somatic System & the Autonomic System
Somatic nervous system: a major component of the peripheral nervous system that transmits sensory
signals to the CNS via nerves and back to the muscles, joints and skin to initiate, modulate and inhibit
movements; specialized receptors.
Autonomic nervous system: regulates the body’s internal en