Psychobiology Flashcards
What is the definition of psycholobiology?
1) the study of the effects of cognition, emotions and experience on animal psychology
2) the school of psychology that interprets personality, behaviour and mental illness in terms of responses to interrelated biological, social, cultural and environmental factors
3) attempt to understand the psychology of organisms in terms of their biological functions and structures
What are psychobiologists aims?
- to understand the human mind and how it affects our behaviours
- ability to predict - want to have this underlying knowledge to predict how people behave and help treat them
- want to understand the relationships between things, in particular the brain and behaviour
Where has psychobiology come from?
1800’s
Freud (functional) vs Kraeplin (somatic)
F - initially a physiologist, then branched off to start psychoanalysis
K - understanding through the physiological - there must be a
physiological event or reason for exhibiting certain behaviours
Describe the case of Anna O
- diagnosed with hysteria, caring for her dying father
- symptoms: partial paralysis, blurred vision, headaches, hallucinations
F view - psychoanalytic view
- ‘hysteria’
- Pappenheim - dubbed it as the ‘talking cure’
- caring for her dying father - kind of obvious why she may have some of these symptoms
K view - wanted a more somatic view of what was going on
- must be something in her physiology causing the symptoms
- connections between brain biology and mental illness
Who was Adolf Meyer?
- ‘dean’ of American psychiatry
- first to really do psychobiology
- took on Kraeplin’s work and ran with it
- saw that people were being locked away if they had a mental illness - stigma attached to mental illness, people did not want to deal with it
- first to conduct autopsies in an attempt to correlate brain lesions with psychiatric diagnoses
What was general paresis?
- a functional disorder
- what you were diagnosed with if something appeared to be wrong
- ‘mental strain of a life of excess’
- reason - didn’t go to church enough
- 1911-1919 - 20% of male admissions into NY mental hospitals had this disorder
What used to be the treatment for disorders such as general paresis?
Kellogg (1897) country retreats for people
- general paresis - caused by living in the city and its conduct a
- go to these country, agricultural settings to get better
- eat fine food and wine etc to cure the disorder
ECT - Bickerton et Al (2009) and Rose et al (2005)
ECT still used as a treatment, for severe depression
Bickerton - investigated the total estimations of ECT as treatment
- did decrease over time as a result of differnt treatments being developed, such as drug treatments (Prozac)
Rose - ECT in BJP
- investigate the information people received before getting treatment
- people did not know what the treatment was - more info needed!
- issue still occurring today - are people able to make their own decisions about their treatment? At what point is the line crossed?
Henry A Cotton - Focal Infection Theory
- reason for a lot maladaptive behaviours - bacteria
- took people’s teeth out
- 1990’s - personal hygiene was not the best
Previously laughed at - why would bacteria cause mental illness?
Coming back into fashion, research has been done into the area
Pizzo et al (2010) - Focal Infection
- periodontal infection may influence systematic health by:
1. bacteria getting into the bloodstream by cuts or lesions in the mouth
2. metastatic injury such as lesions from the effects of circulating toxins
3. metastatic inflammation due to the immunological response to the pathogens and their toxins
Poor oral health is linked to:
Cardiovascular disease, respiratory diseases, diabetes, osteoporosis, preterm low birth weight, pancreatic cancer
Lobotomy - Moniz and Freeman
- surgical operation involving incision into the prefrontal lobe of the brain
- basically entered the brain through the eye sockets
- 52% of the first 623 surgeries yielded good results but did not offer a clinical yardstick for what constituted an improvement
- P’s often had to be re-taught certain skills - how to eat or use the bathroom
- not often successful
Examples of Lobotomy cases
Mrs Hammat - agitated depression and sleeplessness
- drilled 6 holes into the top of her skull
- able to go to the theatre and enjoy the play
- lived for another 5 years
Rosemary Kennedy - JFK’s sister
- needed full time care for 64 years
- stigma - don’t want to show her off due to the popular name?
- just say its learning difficulties instead?
How did we previously find out about the link between brain and behaviour, before we had scanning techniques?
Through autopsies
- Broca and Wernicke discovered their respective types of aphasia
- Phineas Gage?
What do damaged brains tell us about normal brain function?
- can tell us where in the brain certain functions are processed and how these functions get processed
- can gets lots of information
Problems?
- relations may be differnt?
- spatial issue - brain damage does not always affect the same area?
- individual differences in brains too
What is Prosopagnosia?
- the inability to recognise individuals faces
- usually follows after brain damage
- intact intellectual and cognitive function
- preserved low-level visual processing
Damage - to the visual cortex as seeing a face is a visual process
- context becomes very important - since they cannot recognise faces, pathways need to be established so that when you see a face you can say that this is my daughter / wife / sister etc
De Haan et al (2011) - covert and over recognition in Prosopganosia
Presented with a photo of a familiar face - given 2 possible names, one of which was the correct name
PH - could select the appropriate name with above chance accuracy
When asked how he performed this task, he consistently reported that he was just guessing and didn’t experience any confidence in his decisions
Nishimura et al (2009) - Prosopagnosia and face space
Face space = where you can look at and recognise faces
- congenital and acquired Prosopagnosia (as a result of trauma)
Congential:
- did not significantly differ from controls on their ability to say it was a face and recognise a face
- there is face space there but they just aren’t aware of it?
- cannot consciously say they recognise the face
- behavioural outcome is not there - oh I recognise blah-blah
Acquired - displayed the significant difference from the controls
Difference between the two - an inability to recognise faces
- has the face area acquired damage?
- C - already have the tools as they have never know the difference so the brain has re-wired itself
What is face space and what are of the brain is it associated with?
Fusiform gyrus
- part in the middle that says this is a face (eyes, nose etc)
- as you move away from this, you get more and more distinctive
- distinctive faces - further away from the middle
- recognise distinctive faces faster
What is Capgras syndrome?
- converse of Prosopagnosia
- where you can recognise people but you think they are imposters
- this is my mum - no it’s not, it’s an imposter
Ramachandran:
- student from the University of California in a car accident
- several weeks in a coma and then regained consciousness
- mother came to visit - claimed she was another person pretending to be his mother!
Ellis and Lewis (2001) - Capgras Syndrome and skin conductance
- skin conductance - measures emotional responses - sweat!
- SC is higher for recognising familiar faces
- because of the emotional response when you see a familiar face
- significant differences found in normal controls & psychiatric patients
- NO significant difference in the Capgras patients!
- no objective physiological response to people they are familiar with compared to people they are not familiar with
What can Capgras Syndrome and Prosopagnosia give evidence for?
A DOUBLE DISSOCIATION!!!!!
P - inability to recognise faces until more information is given
- feel separate from people until they get more information as they cannot immediately recognise the face
CS - recognise the face but have no emotional response
- evidence for two different pathways that feed into this recognition, processing and understanding of ‘well this is a person’ and whether you can recognise if you like them / if they are a familiar face
- strong evidence for independent mechanisms in the brain?
P - recognising faces = impaired, emotional response = not impaired
CS - recognising faces = not impaired, emotional response = impaired
Dual route of recognition?
P - OFA lesion whilst a Capgras lesion can be found in the dorsal route
What is Blindsight?
- refers to people who had damage to their visual cortex but when presented with stimuli, they are still able to accurately / above chance level to say that a stimulus was present
- eg can accurately point to a small spot of light flashed in their blind field when forced to guess even though they deny seeing it (can’t consciously see it)
- can detect differences in line orientation, colour, direction of motion, basic shapes and facial expressions in their blind field
Santhouse et al (2002) - damage to the corpus callosum
- looked at P’s with damage to the CC
- competed an auditory task
- presentation to right ear crosses the subcortical LH then colossal transfer to the RH for timbre discrimination processing
- damaged CC - difference in reaction times due to bilateral and unilateral lesion placement
- plasticity had taken place - re-wiring of the brain
Gable et al (2013) - global and local targets with the two hemispheres
- global target - is an H presented here (H made up of F’s)
- local target - is there a T presented here (F made up of T’s)
Local - more RH activation
Global - more LH activation.
- difference in processing jobs between the two hemispheres
- ERP’s also demonstrated differences in electrical activity
What does damage to Broca’s area result in?
- left frontal area of the brain
- an expressive aphasia
Deficits:
- Agrammatism - impaired use of grammatical construction
- Anomia - word-finding difficulties
- Articulation difficulties - eg lipstick = lickstip
What does damage to Wernicke’s area are result in?
- left temporal area of the brain
- a receptive aphasia
Deficits:
- poor speech comprehension
- fluent but meaningless speech
Describe Geschwind theory
Do we have isolated parts of the brain that are specialised for specific behaviours?
- damage to one bit - is only one thing affected?
- not just about these area - about the pathways connecting the areas!
- recent studies using spohiscayed brain-imaging techniques have questioned the model
- damage to Broca’s and Wernicke’s area often has no lasting effect on language
- but damage outside the classic areas of the model (especially in the frontal lobes) can cause aphasia
- the extent of language areas varies considerably between individuals
- moving away from the classic, isolated views
- double dissociation???
What is developmental dyslexia?
- specific disability in learning to read despite normal intelligence
- no obvious sensory deficits
- adequate educational or socio-cultural resources
(APA 2000) - main part - phonological processing deficit
- present in 5-17% of the population.
Dual system in dyslexia?
- evidence comes from the existence of two kinds of acquired dyslexia; surface dyslexia and phonological dyslexia
- left side route - allows us to read familiar words - regular and irregular such as dough, bough and trough
- right side route - allows us to sound out regular unfamiliar words or pronounceable non words - anodyne, chint, glab, trisk, asculobatory
What is disrupted in Phonological Dyslexia?
- the letter-sound rule application
- cannot read out pronounceable non-words
- but can read familiar words - not affected!
- damage to the right side route!
What is disrupted in Surface Dyslexia?
- interruption to the meaning
- pronunciation errors
- can accurately read words and non words that comply with the letter-sound rules
- mistakenly pronounce exception words
- damage to the left side route!
What is sleep?
- condition of the body and mind
- typically recurs for several hours every night
- the nervous system is inactive, the eyes are closed, the postural muscles are relaxed and consciousness is practically suspended
What is the purpose of sleep since it constitutes such a large amount of human lifetime?
- ancient humans - the soul left the body during sleep?
> why we may experience fear before we surrender to unconsciousness every night?
Many reasons, still not sure as to why:
Homeostatic regulation, thermoregualtion, tissue repair, immune control, memory processing
What happens to us when we sleep?
- it’s a behaviour
- an altered state of consciousness
- associated with the urge to lie down for several hours in a quiet environment
- few movements occur during sleep (eye movements???)
- nature of consciousness changes
- may experience dreaming and may recall very little of it (the mental activity)
- we speak about a third of our lives in sleep - so there must be an important function to it!
What kind of measures can we use to measure sleep?
Electrophysiological instruments can be used in a sleep lab to assess the physiological changes that occur during an episode of sleep
Electromyogram - EMG - muscle tone
Electroencephalogram - EEG - summated brain wave activity
Electro-oculogram - EOG - eye movements
Blood flow to the genitals
Describe the sleep stages
Found that that we move through these stages of sleep
Wakefulness, non-REM 1, 2,3 and REM sleep
- can see how much time is spent in all these different stages and how this can change due to the influence of different things (eg alcohol)
What is the difference between alpha and beta activity in sleep?
Alpha activity = wakefulness (13-30 Hz)
- desynchrony - low amplitude, high frequency waveforms
Beta activity = eyes closed (8-12 Hz)
- synchrony - high amplitude, low frequency waveforms
How do you conduct a sleep study?
- prepare the sleeper for the electrophysiological measurements
- set up electrode cap to monitor EEG - measured electrical activity across the scalp
- attach electrodes to the chin - EMG - muscle activity
- attach electrodes around the eyes - EOG - monitor eye movements
- other electrodes and transducting devices can be used to monitor heart rate and respiration
What are the two basic patterns of activity from an EEG?
Beta - 13/30 Hz
- rapid fire kind of, irregular, mostly low amplitude
- lots of different processes of the brain are awake and working
- alert to the environment
Alpha - 8/12 Hz
- regular, medium frequency waves
- brain produces this activity when a person is resting quietly
- not particularly aroused, excited or engaged in strenuous mental activity
- can occur when a person’s eyes are open but are much more prevelent when the eyes are closed
Describe Stage 1 of sleep
- transition between sleep and wakefulness
- presence of theta activity
- sharp vertex waves - high amplitude but slow frequency
- brief periods of alpha activity
- slow rolling eye movements, little muscle activity
- hypnagogic hallucinations
- myoclonic jerks
- lasts only a few minutes
Describe Stage 2 of sleep
- EEG is generally irregular
- periods of theta activity, sleep spindles and K complexes
- no eye movements
Sleep spindles - shorts bursts of waves (12/14 Hz)
- occur between 2 and 5 times a minuted during stages 1-4
- play a role in the consolidation of memories
- increased scores of sleep spindles are correlated with increased scores on tests of intelligence (Fogel and Smith, 2011)
K complex
- sudden, sharp waveforms
- usually only found in stage 2
- occur approx 1 per minute
- often triggered by noises
Describe Stages 3 and 4 of sleep
- marked by high amplitude delta activity
- slow-wave sleep
- associated with maladaptive behaviours, particularly in Stage 4; bed wetting, sleep walking and night terrors
Describe REM Sleep
- EEG displays theta activity
- increased brain activity
- looks like wakefulness
- EOG shows the characteristic eye movement
- other physiological changes - increased respiration rate
- no muscle activity - paralysis of voluntary muscles
- stage in which most vivid dreams occur
Riemann et al (2012) - Sleep Structure differences
- different in polysomnographic profiles of a good sleeper & patient with primary insomnia
Insomniac
- more frequent periods of wakefulness and more periods of arousal
- lots of time in stage 2, not as much in the others
- same sleep opportunity and onset
- completely different sleep structures
- too aroused?
Link between sleep and poor mental health
National Statistics (2011) - sleep disturbance is foremost of all primary mental health complaints
Insomnia:
- most widely reported psychological symptom in Britain
- main reason for Benzodiazepine prescribing in primary care
Research into Insomnia and poor mental health
Doctor visits in the US
- increase of insomnia visits from 4.9 million to 5.5 million - 13% increase!
- prescriptions increased from 1999 to 2010 by a 293% increase!
- now recognised as disorder in itself - not something that will just go away
Walker et al (2002) - Insomnia
- sleep dependent motor memory enhancement
- finger tap task where they had to learn a sequence
- different conditions to see where their training was and performance was in relation to sleep
Group b - training at 10 am then pm and then performed after
- significant improvement after the opportunity to sleep
- where the sleep was significantly improved performance on the task
- purpose of sleep - motor memory enhancement
- stage 2 - important in processing and consolidation of sleep
- significant correlations between stage 2 and performance on task
Walker and Stickgold (2006) - Insomnia
- presented P with positive, negative and neutral stimuli
- group had been deprived of sleep
- is there a difference between the sleep deprived and non-sleep deprived group in recall?
- no significant difference for negative and neutral stimul
- significant difference on the positive stimuli
- important - lack of positive stimuli processed - more likely to develop depression?
Baglioni et al (2011) - Insomnia and Depression
- non-depressed + insomnia = 2x risk of depression
- incidence of depression in the insomnia group at baseline (13.1%> significantly higher than no sleep difficulties group
- population incidence of depression is 9.9%
- similar for children, adolescents, working age individuals and older adults
Yoo et al (2007) - sleep and amygdala
- 35 hours total sleep deprivation
- 60% increased activation in the amygdala in the SD group
- 3x increased volume in SD group
- enhanced reaction to negative stimuli
- connection with the medial section of the prefrontal cortex (higher planning) was diminished in the sleep deprivation group
Woods et al (2011) - Insomniacs and what happened during the day
- relationship between sleep quality and impairment in daytime domains
- Posner paradigm - sleep and day times
- predicted that the Insomniacs would have longer reaction times on the night times, more focused on sleep
- found the opposite - longer reactions on the day times
- sleep quality and daytime impairment produce different response patterns
- sleep quality and daytime impairment with the view of insomnia as a 24 hours disorder?
Dixon et al (2006) - Insomnia and health quality
- measured on health and well-being
- how would the poor sleepers fair on this?
- not very well indeed
- co-morbidities with chronic illness and pain interference
- not a long term solution for just giving them drugs - need to do something more?
Biello (2009) age and sleep
- wanted to look at the effects of age and the neuro-chemicals involved in sleep
- typical view of older people - go to bed earlier, wake up earlier, afternoon naps etc
- no difference in timing but there was less of them - Glutamate, NMDA, GRP and HA
How is sleep regulated?
- loss of SWS or REM sleep is made up somewhat on following nights
- not controlled by chemicals
- Siamese twins - same circulatory system but sleep at different times
- bottle nose Dolphins - two hemispheres sleep independently
Neural control of arousal
Stimulate the reticular activating system - wake them up
Stimulate the thalamus - sleep
(experiments done in cats)
What substances are vigilance promoting?
Amphetamine - enhances monoaminergic neurotransmission
Caffeine - blocks adenosine receptors
Nicotine - stimulates cholinergic receptors