Biopsychology (Free Access) | Ace your Psychology Exams!

Practice MCQs

The Nervous system (Read: Behave: The Biology of Humans at Our Best and Worst)

Sensory nervous – carry input messages from sense organs to brain and spinal cord
(Study Tip: senses to brain)
Motor neurons – carry output impulses from brain and spinal cord to the body’s muscles and organs
(Study Tip: motor as in running which requires muscle. Therefore, takes messages from brain to muscles through the spinal cord)
Interneurons – perform connective or associative functions within the nervous system
- most in number
(Study Tip: Inter =in-between)
Glial cells do not send or receive nerve impulses but hold the neurons and their surroundings areas together.
(Study Tip: G for Glial, G for gluing. Holding neurons together)

The Nervous System is divided into two major parts
- Peripheral Nervous System – all neural structure that lie outside the brain and spinal cord
- Further divided into two parts
  - Somatic nervous system
  - Autonomic nervous system
- Somatic nervous system – transmits messages from brain & spinal cord to and from voluntary controlled muscles.
- Autonomic nervous system – Responsible for controlling body’s internal, involuntary (smooth) muscles and glands.
  - Further divided into two categories:
    - Sympathetic nervous system
    - Parasympathetic nervous system
Sympathetic nervous system- works on the arousal function and acts as a total unit.
- Responsible for ‘fight or flight’ response.
- The response is seen with the following behaviour:
  - Increased sweating,
  - pupil dilation,
  - heartbeat increase,
  - breathing increases,
  - lump digestion
Parasympathetic division affects specific organ(s) at a time. In opposition to the sympathetic division it slows down body processes to maintain equilibrium.
- The responses are opposite to the ‘flight or fight response’.
(Study Tip: Periphery meaning everything away from brain and spinal cord)
(Study Tip: two parts, Somatic meaning body and related to voluntary body parts;
Autonomic meaning automatic, therefore, involuntary parts. Further subdivided into Sympathetic and parasympathetic)
(Study Tip: Sympathetic is sympathetic to body and responds to stimuli by fight or flight. Parasympathetic is opposite and slows everything down similar to a slight crude form called paralysis; Remembering anyone will bring the meaning of the other to mind)

Body and Brain are in constant flux to attain Homeostasis i.e. state of internal balance
The Central Nervous System – contains the brain and spinal cord.
- It connect most parts of the Peripheral Nervous System with the brain.
Spinal cord – is 16 to 18 inch long and 1 inch in diameter.
- It is protected by the vertebrae
- Spinal reflexes are stimulus response sequences that can be triggered without the involvement of the brain. This reduces reaction time and helps in emergency situations.
  - 31 pairs of spinal nerves
  - Arranged from top to bottom:
    - Cervical (8)
    - Thoracic (12)
    - Lumbar (5)
    - Sacral (5)
    - Coccygeal (1)
(Study Tip: CT (as in ct scan)-VSCo (as in instagram camera)
3 meninges protect it as well (arranged innermost-outermost)
- Pia
- Arachorid
- Dura
(Study Tip: PADding)

Structure of the Brain (HIND-MID-FORE)

The Hindbrain – lowest and the primitive part of the brain;

Consists of the areas of the brain stem and the cerebellum
Brain stem – supports vital life functions. Consists of the medulla and pons.
Medulla is responsible for:
- Heart rate and perspiration
- Crossover point for sensory and motor nerves from and to right and left sides of the brain
Pons
- Above the medulla and is responsible for
  - Carrying nerve impulses between the higher and lower levels of nervous system
  - Sleep and respiration
Cerebellum
- Looks like a mini brain
- Wrinkled cortex of gray matter and is responsible for
  - coordinating muscular movement,
  - learning and memory
- Alcohol consumption diminishes coordination
- Trivia: Cats have a highly functional cerebellum
(Study Tip: Hind brain = MPC-bellum)
The Midbrain
- Located above the hindbrain
- Consists of the reticular formation, tectum, the cerebral aqueduct, tegmentum, and the cerebral peduncles.
- Contains clusters of sensory and motor neurons
- Responsible for:
  - Visual and auditory relay centres → forebrain
  - eye movements
- Reticular formation
  - Finger shaped, deep within forebrain
  - Acts as a sentry, alerting higher centres and allowing or blocking incoming messages
  - Responsible for: Consciousness, sleep and attention
(Study Tip: mid brain has only reticular formation that important)
The Forebrain
- The most advanced portion from an evolutionary standpoint
- Consists of the Cerebrum
  - All parts such as Thalamus, Hypothalamus, Limbic System, Cerebral cortex, are located in the Cerebrum
- Cerebrum
  - Wraps around the brain stem
  - Two large hemispheres (left and right)
- Thalamus
  - Located above the midbrain
  - Part of the cerebral spheres
  - Switchboard function: sends sensory nerve impulse to appropriate areas
  - Visual, auditory and body senses (balance and equilibrium)
  - Schizophrenia patients have an abnormally functioning thalamus that relays information to parts that do not need that information.
- Hypothalamus
  - Located at the base of the brain,
    - below Thalamus
  - Responsible for:
    - Motivation & emotion,
    - temperature regulation,
    - sleeping,
    - eating,
    - drinking and aggression
    - Regulates endocrine and pituitary gland
  - James Olds found that hypothalamus has pleasure areas where dopamine works and is responsible for rewards and punishments
- Limbic system
  - Located deep within the cerebral hemisphere
  - Responsible for:
    - Satisfying urges that occur in the hypothalamus related to motivation and emotion
    - Inbred in memory as well
  - Two structures exist within the limbic system:
    - Hippocampus
      - Responsible for the formation and retrieval of memories
        Damage can lead to severe impairment of recent memories
    - Amygdala
      - Also known as the fear centre
      - Organises motivation and emotional patterns related to aggression and fear
      - Reward and punishment centres for motivation sectors of limbic system
- The Cerebral Cortex
  - Made up of gray (unmylenated) cells forming the outermost layer of the brain
  - 80% of brain tissue
  - It has fissures that are divided into four lobes based on sensory and motor function
    - The folds of wrinkled cortex looks like a canyon
    - Some division made by the fissures don’t involve sensory or motor function and are known as Association cortex
      - Responsible for mental processes of thought, memory and perception
  - Frontal lobe (planning and execution)
    - self-awareness, planning, initiative and responsibility and emotional experience
    - Prefrontal cortex
      - Located behind forehead,
      - Responsible for:
        executive functioning,
        goal setting,
        judgement,
        impulse control
    - Motor cortex
      - Responsible for more than 600 voluntary muscles in body
      - Located at the rear end of frontal lobe
      - Body parts are arranged upside down in the motor cortex
        Information from legs is responded from the top portion of the frontal lobe
        Information from the upper portions of the body is responded by the lower portion of the frontal lobe
  - Parietal (temperature)
    - The sensory cortex
      - Receives inputs for heat, touch and cold
        Balance and body movements
      - Located behind motor cortex, and in front of parietal lobe
      - Same upside down principle as motor cortex
  - Temporal lobe is responsible for hearing
  - Occipital is responsible for vision and sight
- Speech Comprehension and Production
  - Werwick’s area
    - located in the temporal lobe (left hemisphere)
    - Responsible for speech comprehension (written or spoken)
  - Broca’s area
    - located in the frontal lobe (left hemisphere) close to motor cortex
    - Responsible for facial muscle movement and speech production
  - Damage to either leads to:
    - Agnosia – inability to recognise familiar objects
    - Aphasia – inability to comprehend and formulate language due to damage to specific brain regions
- Association cortex
  - mental function of perception, language and thought
    - responsible for superior cognitive ability
(Study Tip: Everything else is here!)
- Brain lateralization
  - Refers to the relatively greater localization of functions in each hemisphere
    - Corpus callosum – connects left and right hemisphere
  - Left hemisphere
    - Responsible for speech production, comprehension, math/arithmetic ability, logical abilities, and positive emotions
    - Right portions of the body are controlled by the LH
  - Right hemisphere
    - spatial relations, face recognition, and negative emotions
    - Left portions of the body are controlled by the RH
(Study Tip: link one attribute of left brain and right brain to right and left handed people respectively. Consolidate that information)
- Split Brain – Roger Sperry
  - When the corpus callosum is damaged and the hemisphere begin acting independently of one another
- Brain Plasticity also known as neuronal plasticity – ability of the neurons to change in structure and function.
- The production of new neurons in the nervous system is called Neurogenesis.
  - Neural stem cells – uncommitted cells that can mature into any neuron of a degenerative area

Neurotransmitters

Acetylcholine (Ach) – muscle activity and memory. Reduced when suffering from Alzheimer’s disease
- Affects areas of Pons and basal forebrain
(Study Tip: Ach as in ache, muscular ache, affects muscles)
- Norepinephrine
  - excitatory and inhibitory, depending on site
  - neural control of learning, memory, wakefulness and eating
  - Depression, stress and panic disorders
(Study Tip: Neither/nor-ephinephrine – meaning both inhibitory and excitatory)
- Serotonin
  - excitatory and inhibitory
  - mood, sleep, eating, arousal
  - Depression, sleeping-eating disorders, OCD
  - secretion – Ralphe nuclei
(Study Tip: nin/non: meaning both inhibitory and excitatory)
- Dopamine
  - excitatory,
  - movement, emotional arousal
  - Parkinson, depression and schizophrenia
(Study Tip: Dopa–Mine is exciting; excitatory)
- GABA
  - inhibitory,
  - motor system
  - Huntington’s disease, loss of motor control and personality change
(Study Tip: GABAsounds boring. It’s definitely inhibitory)
- Endorphin
  - Inhibitory
  - inhibits pain transmission
  - Insensitivity to pain, hypersensitivity, immune problems
(Study Tip: End-orphine is inhibitory)
- Neuromodulators are messengers released from neurons in the central or peripheral nervous system to affect a group of neurons
  - They have a more generalized effect on synaptic transmission

Behavioural genetics and environment

Behaviour genetics – study how genetics and environment factors influence psychological characteristics
- Degree of similarity of responses of genetically similar people gives an indication of the impact of genetics
Heritability
- Heritability statistic estimates the extent to which the difference in specific phenotype within a group of people can be attributed to their differing genes.
Genetic basis of behaviour
- Genotype – the specific genetic makeup of an individual
  - compared to a computer software
  - Genes present from birth
  - May or not may not manifest
    - dependent upon other genes which hinder or help this gene activate
- Phenotype – are the observable characteristics of the individual.
  - The genes that are present and are expressed,
  - Difference between genotype and phenotype is that the genotype has all the genes but not necessary that all will be expressed
Major contributor of gene understanding
- Gregor Mendel
Organic factors of genes affect characteristics.
- Nucleus of all cells constituted by chromosomes
  - 22 identical pairs in humans called autosomes
- Sex cells are called allosomes as the gene is different in shape, size and length compared to other chromosomes
- A chromosome is a double stranded, tightly coiled molecule of deoxyribonucleic acid (DNA).
- All information of heredity are in four chemical bases:
  - Adenine
  - Cytosine
  - Thymine
  - Guanine
(Study Tip: ACT-G)
- Alleles are alternative characteristics that are developed due to alternative genes/mutation
- Dominant genes will display characteristics
- Recessive genes will not display characteristics unless two similar recessive genes are combined.
- Polygenic transmissions occurs when many genes contribute to make one single dominant trait
Experience shapes behaviour in two ways:
- Fixed action pattern
  - an unlearned automatic response triggered by a particular stimulus
- Species adaptation
  - learning is not transferred by genes but through natural selection genetically based characteristics that enhance the ability of a species to adapt is transferred
Two types of research studies to test genetics and heritability of behaviours
- Family studies – Degree of similarity of behaviour of genetically similar relatives in specific traits to the person in question
- Adoption studies – Degree of similarity of behaviour of adopted children with genetically similar (biological) parents and adoptive parents

Brain and other concepts

Intelligence
- Identical twins reared together
  - correlation is high
- Identical twins reared apart
  - correlation nearly as high
- Fraternal twins
  - IQ of adopted children correlate similarly with both their biological parents and adoptive parents
  - (no single gene for intelligence)
  - Genetics/Heredity account for 50-70% change in intelligence
- Siblings reared together have a high correlation in their IQ
- Correlation of .32 between unrelated adopted children living together
- Difference of home environment is more important in lower socio-economic conditions
  - Evidence: children in impoverished homes moving to better homes show increase in IQ by 10-12 points.
Schizophrenia: Studied by Seymour Ketty
- Schizophrenia (12% similar genes)
- Twin studies
  - compared trait similarities in identical and fraternal monozygotic twins
  - Trait similarity a.k.a. high concordance rates
  - High correlation in case of schizophrenia with family members
Personality (Reading: Personality Psychology)
- Genetic differences account for .50 correlation between similar genotype individuals
- Important finding was that family environment played very limited role in determining personality, except when extremes of neglect and abuse occur.
- Similar results for twin and adoptive studies.
Gene-environment interaction
- The environment cannot affect the genotype but only its expression and phenotype
- Reaction range
  - Is the measure of how much the environment can affect genes
- Intellectual growth depends on both factors i.e. genes and environment
- Evocative influence
  - A child’s genetically influenced behaviour may evolve certain responses from others
  - Introvert/extrovert children
- Gene experimentation
  - Knockout procedure
    - A particular function of a gene is removed
All vertebrates have a bilaterally symmetrical body plan
Anatomy of dissected in the following manner
- Proximal – closer to the trunk
- Distal – away from the trunk
- Lateral – away from midline
- Medial – closer to midline
- Anterior – front side
- Posterior – back side

Endocrine system – consists of numerous hormone secreting glands distributed throughout the body.
- Messages to the body are distributed through hormones secreted via glands
- Hormones are chemical messengers secreted into the bloodstream

Brain decides which impulse to send, between endocrine and nerve impulse, or both
Hormones affect us from prenatal stage
- They affect aggressiveness, sex differences, immune system and so on
Immune system
- foreign substance (antigens) are removed by antibodies
- Stress, depression, negative thinking reduce immune functioning
- Candence Pest suggested that the nervous, endocrine and immune system are related
Glands are organs in the body that secrete chemicals
- Endocrine glands
  - secrete enzymes into the ‘bloodstream’ called hormones, usually from sympathetic division of ANS
  - Hormones affect behaviour and emotions through organs like heart, pancreas, sex organs.
- Pituitary gland also known as Master gland
  - controls all other glands
  - located below hypothalamus
  - influences events related to pregnancy – production of milk, onset of labos, salt and water
Growth hormone
- regulates and controls increase in size of body parts
Pineal gland
- secretes melatonin
- located nearer to the back of brain
- regulates sleep wake cycle (Read: Why We Sleep)
Thyroid gland
- secretes thyroxin
- located inside neck
- regulates metabolism
Pancreas
- secretes insulin and glucagon
  - low insulin = diabetes
  - high insulin = hypoglycaemia
- located in torso
- regulates blood sugar
Gonads
- secretes androgens, oestrogen, progesterone, and testosterone
- located in the ovaries (females) and testes (males)
- regulates sexual behaviour along with the brain
Adrenal gland
- on top of each kidney
- Two types:
  - Adrenal medulla
    - secretes epinephrine and norepinephrine
    - regulates stress and sympathetic arousal
  - Adrenal cortex
    - secretes 30 different hormones called corticoids (steroids)
    - regulates salt intake, stress reaction, sex hormones
  - Cortisol
    - released under stress
    - releases glucose into bloodstream
    - provides energy to body and brain by burning fatty acids from fat cells

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