Psych Part 3 Flashcards
Early brain development
At birth humans have more neurons than at any point in the rest of their lives. Though neural networks are significantly reduced.
Brain development 3 - 6
rapid growth in the frontal lobes - thinking, memory, language (last to develop)
Note that memory for most adults usually starts around 3.5 years.
Social development and Attachment
Demonstrate Stranger anxiety from 8 - 12 months onward.
Harry and Margret Harlow
Demonstrated the importance of “contact comfort” with rheuses monkeys.
Mary Ainsworth
“Strange Situation Experiments”
Showed different responses from infants that were securely versus insecurely attached.
Secure with mom: explore and play
Secure without mom: distressed, but quickly consoled when mom returns
Insecure with mom: will not leave mom
Insecure without mom: cry and remain upset; demonstrate indifference to departure/return
Parenting Styles
Authoritarian
Permissive
Authoratative
Authoritarian parenting
strict rules; unconditional obedience; punishment; demanding; no rule explanation; not responsive to children
Children: may be shy, aggressive, and have lower self-esteem
Permissive
Few and inconsistent demands; little discipline; very loving;
Children: may lack self-discipline, be self-involved, show poor social skills
Authoritative
Agency given to children; rules and discipline are enforced; consistency and fairness
Children: happier; emotional control; social skills; confident
Brain Changes in Adolescence
three major changes:
1. cell proliferation (prefrontal lobes; limbic system, which develops fastest)
- Synaptic pruning
- Myelination
Behavioural Neuroscience
Focus on neurophysiological correlates of behaviour.
Brain lesions/neuroimaging make up 2/3 of the studies techniques.
ex. Phineas Gage damage to the prefrontal cortex.
Limitations: difficult to do a dbl blind experiment.
Neuroimaging techniques, Structural Imaging
Computerized (axial) tomography (CT or CAT)
Magnetic Resonance Imaging (MRI)
CT/CAT Scan
Uses x-rays; takes a 3d scan of the brain or a portion of the brain using cross sectional slices (tomography).
Pros:
Rapid acquisition; less cost; more open; less noisy; allowed to have medical implants; preferred for illness that have a time limit (stroke)
MRI
Magnets cause spin alignment of protons, that then emit radiowaves
Pros:
Quality; high resolution of soft tissue; no exposure to X-ray
Neuroimaging techniques, functional imaging
Electroencephalography (EEG)
Magnetoencephalography
Functional MRI
Positron Emission Tomography
Electroencephalography
electrodes on scalp measure voltage fluctuations of ionic current; provides information of grouping of neurons referred to as brain waves; HIGH temporal resolution.
Useful for disorders with variable brain functioning across the brain.
Adv: little hardware; low cost; tolerance of movement; high temporal resolution; no claustrophobia
Disadv: low spatial resolution; poor measurement of sub-cortical regions; poor signal to noise.
Magnetoencephalography
Records magnetic fields produced by the brain.
Uses highly sensitive magnets known as an ARRAY of SQUIDY (Superconducting Quantum Interface Devices)
Similar adv/disadv as EEG; however requires a magnetically shielded room and is bulkier. Importantly though, it has better spatial resolution than EEG.
fMRI
Combines MRI images that are less than a second apart.
Can show changes in O2 levels which is a proxy for blood flow.
Adv: Safer than PET; high location precision; lower cost than PET
Disadv: remain still in cramped area; cannot ask subjects questions during MRI
PET
3D images of metabolic process over time (can monitor change in movement and concentration of the isotope). Requires injection of a positron emitting radionucleotide tracer that is attached to a biologically active substance (ex. Glucose).
Often CT and PET is a combine procedure.
Spinal cord
implicated in reflexes, walking, urination, sex organ function
Medulla
Connects spinal cord to the rest of the brain;
Acts as a relay to other parts of the brain;
Regulates autonomic functions
Respiratory rythmicity
Coughing and sneezing
Hindbrain
Medulla
Pons
Cerebellum
Pons
Connects brainstem and cerebellum
Controls some autonomic function
Controls movement balance and antigravity movement
Cerebellum
integration centre for complex movements
Receives input from vestibular apparatus
Acts as relay to thalamus
Excitatory
Midbrain
Relay for audio-visual info
Contains much of the reticular activating system
Positive muscle tone
Brainstem
Pons, medulla, midbrain
Forebrain
Diencephalon - thalamus and hypothalamus
Telencephalon - formed by two hemispheres (left is normally dominant for speech); (right is normally visual-spatial and reasoning/music)
Corpus Callosum
Connects the two brain hemispheres
Cerebrum
Largest region of the brain.
two hemispheres that include cerebral cortex with 4 lobes:
Frontal - executive
Parietal - general sensation/taste
Occipital - Visual sensation
Temporal - auditory/olfactory, memory language and complex emotion
Basal Nuclei
Deep in cerebral hemispheres - voluntary motor control; procedural movement; works in conjunction with the cerebullum, muscle tone.
Inhibitory.
Limbic system
Between cerebrum and the diencephalon
Structures:
Amygdala
cingulate gyrus
hippocampus
interacts with hypothalamus and the prefrontal cortex
Also associated with the insula which connects to the lateral hypothalamus
Seratonin
Mood, digestion, sleep, memory, sexual desire
Pathways project from the raphe nucleus to the Striatum, Nucleus accumbens, frontal cortex.
Melatonin
Circadian rythm
Sleepiness
Sleep initiation
GABA
Lack of GABA can result in anxiety, depression, ADHD, panic
ACh
neuromuscular junction, parasympathetic nervous system
Glutamate
Shortages result in fatigue, low concentration
Dopamine pathways
Three:
Mesolimbic - natural pathway; for pleasure, key in addiction, nucleus accumbens is the main reward centre (synapse to here).
Nigrostriatal - movement and coordination
Mesocortical - higher functions
Hormones with a psychological effect
Cortisol
Oxytocin - trust, social bond, sexual reproduction, mother-infant bond
endorphins
leptin - regulation of energy; inhibition of hunger
Memory as an organized network
Nodes are individual ideas
Association between nodes, are connections between ideas.
A node is not activated until it reaches a response threshold.
Explains why hints can be helpful
Spreading activation suggests that activation of one node may prime another node.
Schizophrenia neurobiology
Hypoactivation of frontal lobes result in negative symptoms.
Decreased size of hippocampus results in decreased working memory
Smaller brains as a result of atrophy
Increased ventricles (canyons) and enlarged sulci/gyri
Excess levels of dopamine
Depression
Decreased function of dopamine; seratonin; norepinephrine
