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PSYN824 week 4 2011

PSYN824 week 4 2011. Recap PD and HD, and key basal ganglia structures Explain the anatomical boundaries of the four lobes visible from a lateral view and the functions of the hidden “fifth lobe” Describe the research that links mirror neurons with action perception and action preparation

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PSYN824 week 4 2011

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  1. PSYN824 week 4 2011 Recap PD and HD, and key basal ganglia structures Explain the anatomical boundaries of the four lobes visible from a lateral view and the functions of the hidden “fifth lobe” Describe the research that links mirror neurons with action perception and action preparation Understand the relationship between damage in Broca’s area and Broca’s aphasia, and other roles of Broca’s area Describe the common and uncommon disorders associated with damage to the frontal lobe Describe the neuropathology, and neuroanatomical changes associated with Alzheimer’s disease and the fronto-temporal dementias, and the characteristic cognitive and behavioural changes Describe the characteristic cognitive and behavioural changes associated with damage to the amygdala

  2. Recap internal, external and extreme capsules, mammillary bodies, hippocampus, caudate, putamen, internal and external segments of globus pallidus, see the septum pellucidum and insula

  3. Blumenfeld (2002)

  4. Blumenfeld (2002)

  5. Areas of interest in frontal lobes: • Broca’s area (Brodmann’s area 44 and 45) • Broca’s aphasia: decreased fluency and prosody, shortened length of speech, altered grammatical form • Broca’s aphasia: • B.L: Wife is dry dishes. Water down! Oh boy! Okay Awright. Okay ...Cookie is down...fall, and girl, okay, girl...boy...um... Examiner: What is the boy doing? B.L.: Cookie is...um...catch Examiner: Who is getting the cookies? B.L.: Girl, girl Examiner: Who is about to fall down? B.L.: Boy...fall down • From http://pages.slc.edu/~ebj/IM_97/Lecture10/L10.html

  6. The "cookie theft" picture from the Boston Diagnostic Aphasia ExaminationPlaza et al (2008) ’While the mother washed the dishes without [paying] attention looking through the window the water in the sink started to overflow, In the mean time, her son and daughter tried to steal some cakes from the top cupboard. Her son had to stand on a chair [stool], that was falling over” .

  7. What role is played by Broca’s area ? • A role in understanding action ? canonical neurons and mirror neurons in monkeys • Mirror neurons (MN) fire both when we act and when we observe or hear the actions of others. • Do not fire in response to visual presentation of word describing action • A small proportion of neurons in ventral Premotor cortex and Inferior Parietal lobule (IPL) are MNs, probably exist in many brain regions including anterior insula and Broca’s area In humans: More activity when viewing transitive gestures (involving an object) than intransitive (e.g., waving goodbye) Apraxia: an inability to carry out learned, skilled motor acts, despite preserved motor and sensory systems, comprehension

  8. 2. Syntax Sleep green furiously ideas colourless Colourless green ideas sleep furiously Making judgements about syntactically different sentences activate Broca’s area e.g., the policeman arrested the thief vs the thief was arrested by the policeman Making judgements about semantics activates BA47 e.g. the man was attacked by the pitbull vs the man was attacked by the corgi

  9. Motor areas: primary motor cortex, premotor and supplemenatry motor ares

  10. Owen et al (2006) reported a case where a 23 yo woman in VS for five month after TBI was able to “willfully modulate” her brain • Asked to imagine playing tennis (thinking of the ball volleying back and forth over the net) or walking through her own home, imaging what she could see • Increased activity in supplementary motor area (SMA), and parahippocampal gyrus (PPA), posterior parietal lobe (PPC) and lateral premotor cortex (PMC), respectively

  11. D’Ausilio et al (2009) Current Biology, 19, 381-385 Effect of TMS on RTs show a double dissociation between stimulation site (tongue M1 and Lip M1) and discrimination performance between class ofstimuli (dental or tongue related (/d/ /t/) and labial or lip related (/b/ or /p/sounds ). The y axis represents the amount of RT change produced by the TMS stimulation.

  12. Lahav et al (2007) J Neuroscience, 27, 308-317does Broca’s area link motor planning areas with previously heard or seen actions

  13. Clinical relevance of MN:Some of the core symptoms of autism spectrum disorder (linguistic and social difficulties) might result from difficulty experiencing or understanding goals of others Lhermitte’s environmental dependency syndrome Stroke rehabilitation Yavuzer et al (2008) Archives of Physical Medicine and Rehabilitation, 89, 393-398 reported from a well controlled study that “mirror” therapy (30 min a day) in additional to conventional rehab over 20 weeks improved function in paretic hand and on measures of overall rehabilitation (social, communication, locomotion) status

  14. Dorsolateral PFC • order (or the capacity to perform sequencing) link with confabulation • Working memory • Executive function: planning, using feedback, modifying behaviour (including switching and inhibiting): poor performance on WSCT, Trails B, Hayling sentence completion; Lhermitte’s environmental dependency syndrome

  15. Channon and Crawford (1999) You are asked to give advice to a colleague who can’t sleep because the neighbour’s dog keeps him awake. They have spoken the neighbour’s who say they can’t stop the dogs barking • attempt to negotiate again with the neighbours and find a workable solution • take it up with the landlord or the council • poison the dogs • shoot the dogs • bribe them • make a loud noise to counteract their noise • threaten them with violence

  16. OFC or ventromedial cortex Social brain ? • Humour • Empathy • Restraint

  17. The famous case of Phineas Gage image taken from p 106 Westen et al

  18. “The equilibrium or balance, so to speak, between his intellectual faculties and animal tendencies seems to have been destroyed. He is fitful, irreverent, indulging at times in the grossest profanity, manifesting but little deference to his fellows, impatient of restraint or advice when it conflicts with his desires, at times pertinaciously obstinate, yet capricious and vacillating, devising many plans of operation, which are no sooner arranged then they are abandoned in turn for others appearing more feasible. A child in his intellectual capacity and manifestations, he has the animal passions of a strong man” taken from Kolb & Whishaw 5th edition

  19. Grabbing someones else’s steak at dinner because it looks bigger Getting up half way through a dinner party and going to watch TV Boast to wife about having affairs Going to bed when friends come to visit Making inappropriately personal remarks to work colleagues or people in the street Exaggerating wildly in accounts of life (running 1000 kms a week) Overeating, especially of sweet foods Urinate/masturbate in public shoplifting not take turns in conversation collect rubbish in handbag criticize hosts house when visiting ask police to help them find the driver of a car so they can kill them

  20. Namiki et al (2008) Neurocase. 14(6):474-9, describe case HN “apathetic and indifferent. He often left home and wandered about, he urinated in inappropriate places, he occasionally recalled minute past events that elicited his anger, which he then directed at his family. At work, he rented out the land that was used to park his cranes to others at unreasonable rates, and therefore had to find another place to park his own cranes. He made random purchases, and entered into contracts without completely understanding their content”

  21. Anderson, Bechara,, Damasio, Tranel and Damasio (1999) Impairment of social and moral behavior related to early damage in the human prefrontal cortex. Nature Neuroscience, 2(11) 1032-1037 “Subject A was 20 years old at the time of the study. She has been run over by a vehicle at age 15 months, she appeared to recover fully within days. ….at age three she was first noted to be largely unresponsive to physical and verbal punishment. Her behaviour became progressively so disruptive that, by age 14, she required placement in the first of several treatment facilities. Her teachers considered her to be intelligent and academically capable, but she routinely failed to complete assigned tasks. Her adolescence was marked by disruptive behaviour in school and home….she stole from her family and from other children and shoplifted frequently, leading to multiple arrests. She was physically and verbally abusive to others. She lied chronically. Her lack of friends was conspicuous. She ran away from home and treatment facilities. She exhibited early and risky sexual behaviour leading to a pregnancy at age 18. Contingency management in residential treatment centers and the use of psychotrophic medications were of no help. After repeated putting herself at physical and financial risk, she became entirely dependent on her parents and on social agencies for support and oversight of her personal affairs. She did not formulate any plans for the future and sought no employment. Whenever a job was arranged, she was unable to hold the job due to lack of dependability and gross infraction of rules. Affect was labile and often poorly matched to the situation…she never expressed guilt or remorse for her misbehavior. There was little or no evidence that she experienced empathy and her maternal behavior was marked by dangerous insensitivity to the infant’s needs. She blamed her misdeeds and social difficulties on other people and denied any difficulties with cognition or behavior”

  22. Clinical Syndromes vsneuropathological presentation in neurodegenerative diseases • In all of the neurodegenerative diseases there are neuro-pathological markers. • Types of microscopic lesions: • Amyloid plaques • Neurofibrillary tangles • Lewy bodies • Tau positive lesions • Pick’s bodies • Prion plaques • Within these lesions, different types and mixes of misfolded proteins can be identified (e.g, tau, Ubiquitin, ά-Synuclein, TDP-43) • Different distribution within the fine structure (neurons vs glia, cytoplasm or nucleus of neuron) and regional distribution within the cns

  23. Fronto-temporal dementias aka frontotemporal lobardegeneration • Treatment refractory • Strong genetic component (chromosome 17) • Clinical phenotype has not always been a good predictor of underlying pathology at the cellular level or patterns of atrophy Characterized by • Insidious onset • Progressive (i.e. neurodegenerative) • varying degrees of personality change, executive dysfunction and language impairment • selective vulnerability of areas of grey matter

  24. Fronto-temporal dementias Major clinical syndromes are the • Behavioural variant (left side and right side variants) • Language variant: Primary progressive aphasias (PPA) (semantic dementia, nonfluent PPA, and logopenic variants) • Motor type (corticobasal degeneration, motor neuron disease) “knife-edge” appearance of the atrophy in various cortical regions

  25. Semantic dementia or primary progressive aphasia-plus syndrome’ What is preserved • orientation in time • episodic memory • simple calculation • drawing skills • word repetition • syntax • Fluent speech • Phonemic fluency What is impaired, with increasing progression • person knowledge • naming • word finding • semantic memory • category fluency • autobiographical memory (reverse Ribot gradient) • social functioning (apathy, behavioural rigidity, circumscribed interests and ritualistic behaviour, bizarre food choices, loss of empathy)

  26. Hodges and Patterson (2007) Lancet Neurology, 6, 1004-1014 E: “Hippopotamus, can you say that?” P: “Yeah, hippopotamus” E: “What is a hippopotamus?”, P: “A big animal” Or P “I think I’ve heard of a hippopotamus but I can’t say what it is” E: “can you tell me about the last time you were in hospital ?” P: “ that was January, February, March, April last year, that was the first time, and eh, on the Monday, for example, they were checking my whatsit, and that was the first time my brain was shown, you know, you know, that bit [indicates the left] not that one, the other one was OK, but that one was lousy, so they did that, and then like this [indicates scanning by moving his hands over his head] and I was probably a bit better then than what I am now”

  27. Hodges and Patterson (2007) Lancet Neurology, 6, 1004-1014

  28. Semantic loss shown by drawings from memory of two animals Figures from Rascovsky et al (2009) Brain 132,2609-2616 Hodges and Patterson (2007) Lancet Neurology, 6, 1004-1014

  29. Behavioural variant • Change in eating habits (gluttony, preference for sweet foods) • Disinhibition shown in inappropriate behaviours (inappropriate touching, • Apathy • Poor judgment • Prosopagnosia

  30. Insula (Island of Reil) • Contains gustatory cortex (taste cortex) • Recognition of facial expression of disgust in single cases and HD • cortical pain processing: cases of asymbolia Insula: http://library.med.utah.edu/WebPath/HISTHTML/NEURANAT/CNS368A.html

  31. Lerch et al (2005) Cerebral cortex,15, 995-1001 significant cortical thickness decline in medial temporal lobes, temporal , frontal and parietal lobes in Alzheimer’s disease

  32. Gilbertson et al (2002) Nature Neuroscience, 5(11) 1243-1247

  33. Murray (2007) Trends in Cognitive Sciences, 11(11) 489-497amygdala from http://library.med.utah.edu/WebPath/HISTHTML/NEURANAT/CNS368A.html

  34. Adolphs et al (2005) Nature, 433, 68-72

  35. Cristinziu, N’Diaye et al (2010) Brain, 133, 248-261 and N’Diaye etal (2009) Emotion, 9, 798-806

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