dorsal view
DESCRIPTION
Dorsal View. SFS. M1. S1. SPL. IPS. Fronto-parietal attention/Working memory networks. DLPFC. IPS. FEF. IPS. Ventral PFC- regulation, response inhibition. Lateral, Medial OFC. Relational Complexity test. Distractor Control. Kroger, Sabb, Fales, Bookheimer, Cohen, Holyoak 2002. - PowerPoint PPT PresentationTRANSCRIPT
Dorsal View
SFS
SPL
M1
S1
IPS
Fronto-parietal attention/Working memory
networksIPSDLPFC
IPS
FEF
Ventral PFC- regulation, response inhibition
Lateral, Medial OFC
Relational Complexity testRelational Complexity test
Kroger, Sabb, Fales, Bookheimer, Cohen, Holyoak 2002
Distractor Control
Memory systems
• Hippocampal– New associations– Episodic - temporal signature– Case examples– Tests– Paired associate learning– Effect of retrieval cues
R vs. K• Eldridge et al have shown the HC is
selectively involved in R, not with K.
Frontal contributions to memory
• Attention to incoming information
• Organization of incoming information– Pre-organized– Semantic categorization
• Working memory capacity
• Organized memory retrieval
Frontal lobe memory deficits
• Information size effects (supraspan)– LM story 2 second rep;
• Interference (proactive)– Eg: CVLT 5,7,10,9,8
• Benefit from cues• Reduced spontaneous categorization• Confabulation• Prospective memory impairment
Basal Ganglia and learning
• HM and tower of Hanoi
• Probabalistic classification
• Language learning and grammar
• Sequence learning
• Parkinsons vs HC amnesia patterns
• Social learning
Striatum is Involved in Language & Striatum is Involved in Language & CommunicationCommunication
(14,6,0)
• Artificial grammar learning (Lieberman et al., 2004)
• Other forms of statistical learning
• Individuals with autism have deficits in syntax after acquisition of language (Tager-Flusberg &
Joseph, 2003)
Grammatical > Non-GrammaticalGrammatical > Non-Grammatical
Lieberman et al., 2004 J Cog Neuro
Word Segmentation & Language Word Segmentation & Language LearningLearning
• Language delay is a core feature of autism
• Identifying word boundaries is one of the earliest steps in language learning (Kuhl 2002)
• Infant studies suggest heavy reliance on statistical learning for word segmentation (Saffran et al., 1996; Aslin et al., 1998)
• Prosodic cues (e.g., stress) aid speech parsing (Johnson & Juscyzk, 2001; Thiessen & Saffran, 2003)
• Adapt well-established paradigm from infant literature
Implicit Language Learning StudyImplicit Language Learning Study
ga
ba vupo
no ko
mu
gi
ka fifu
vi
novuka pofimuvikoga bafugi
lidura vorifamanuto nimolu
ri
vo
ra mo
li
fadu
lu
nu
mato
nipabiku daropigolatu tibudopa
la
tu pitibu
goku da
do ro
bi
UnstressedLanguage
Transitional
Probabilities
Only
nimoluvorifaliduramanuto…
RandomSyllables
No Transitional
Probabilities
No Prosodic Cues
kagipovuganomubakafufibako…
StressedLanguage
Transitional
Probabilities
+ Prosodic Cues
pabikugolatudaropitibudo…
Implicit Language Learning Implicit Language Learning ParadigmParadigm
StressedStressed
LanguageLanguage
UnstressedUnstressed
LanguageLanguage
RandomRandom
SyllablesSyllables
TIME (seconds)
144s144s 144s30s 30s
Comparisons with Baseline (Rest) in typical adults
Random Syllables
LHRH
Unstressed Language
Stressed Language
LHRH
LHRH
McNealy et al., under review
Implicit Learning and Reward• Probabilistic Classification Task• Reported by Knowlton and Squires- impaired in PD, intact in amnesia• Inversely related to hippocampal activity• Reward variant- social vs monetary
– Stimuli predict a given outcome (1 or 2) either 17% 50% or 83%– Reward and Cognitive (Correct / Incorrect) feedback
• Reward type varied: Monetary Rewards or Social Rewards
– Equal number of reward and cognitive feedback trials
Source: D. Ghahremani
“1”or“2”
Response
3.75 - 6.25 s
2.5 - 5 s
MonetaryFeedback
Facial Emotions: Experimental Paradigm
“Match” “Label” Control
Match Expressions: Perception only; implicit emotional processingLabel Expressions: Explicit cognitive analysis
Match Affect- normal adults
Hariri et al., 1999
amygdala
face area
-seeing negative face expressions activates Face and Fear brain centers
Label Affect
Hariri et al., 1999
amygdala
-interpreting negative face expressions activates Face brain center …
Cortical Influence During “Label”
Hariri et al., 1999
-this frontal lobe region regulates and controls Fear brain centers
Bipolar Disorder- Manic State: Altshuler et al 2005
fMRI in Mania (Altshuler et al 2005)
fMRI of Panic Imagery (Bystritsky et al 2001)
Emotional Face Processing in OCD (S. Rausch)
Disgust and Threat Responses in OCD (Shapiro
2002)
Threat
Disgust
Control OCD
• A dysfunctional mirror neuron system (MNS) in autism? (Williams et al 2001)
Mirror Neurons and Autism
• Mirror neurons: class of neurons first discovered in ventral premotor cortex (area F5) of the macaque (Gallese et al 1996; Rizzolatti et al 1996); Pars opercularis (BA 44), inferior frontal gyrus, is human homologue.
• Neurons fire during both the performance and observation of motor behavior; respond to intention: only fire for meaningful actions
Mirror Neuron function in autism: Imitating and Observing
emotions
2 Separate Functional Runs“Just look at the expression on each face”“Imitate the expression you see on each face”
2 s
2 s
2 s
+
+
+
facesAngryFearfulHappySad
Neutral
I. Watch facesII. Imitate expressions
ASD Imitate t
1
2
3
4
5
6
0
p<.05, corrected at cluster level
LR
TD Imitate
LR
Activity During ImitationActivity During Imitation
Imitate:TD > ASD
LR
Visual areas
Motor areas
Mirror neuron area
Imitation: TD > AutismImitation: TD > Autism
z: 8
L R
Anterior Insula
Connection from mirror centers to emotion centers
z: -12
L R
Amygdala: fear centersNegative faces
Ventral striatum:Reward Centers(happy faces)