2. Not much has changed in the last
billion yearsâŚ
⢠Basic input-output
organization
⢠Sensory apparatus
⢠Effector apparatus
⢠More or less complex
links between
perception and action
⢠Slightly elaborated in
humansâŚ
4. Frontal Lobe Anatomy
⢠Medial Frontal Gyrus (BA 6 posterior, 8 anterior)
⢠SFG (6,8,9,10,11; posterior to anterior as your
curve around the frontal pole)
⢠MFG (6,8,9,46,10,11)
â 6:posterior;
â inferior bank of SFS: p-a 8,9,10,11
â Superior bank of IFS: p-a 9,46,47
⢠IFG (44(opercularis) 45(triangularis) 47 (orbitalis)
⢠Gyrus Rectus (11); orbital gyrus (lateral to GR;
11(12)-47, connects with IFG-orb)
5.
6. Key to Function: Frontal Lobes
are Well Connected!
⢠Frontal division recapitulates thalamic
anatomy
â One method for defining cortical regions relies
on the thalamic projection system
⢠Frontal âcircuitsâ more important than
frontal âregionsâ
⢠Frontal âsystemsâ mediate activation states
across the entire brain
7. NUCLEUS MAJOR INPUT MAJOR OUTPUT FUNCTIONS FUNCTIONAL CLASS
Anterior
from mammillary body
of the hypothalamus
cingulate gyrus of
limbic lobe
mediates visceral,
emotional information specific, limbic
Ventral
Anterior
globus pallidus, substantia
nigra and intralaminar and
midline thalamic nuclei
premotor and
primary motor
cortices motor specific motor
Ventro-
lateral
Contralateral cerebellar
hemisphere through
superior cerebellar
penduncle, globus pallidus
primary motor cortex
motor: coordinates
basal ganglia with
cerebellum specific motorVentral
Posterior
(lateral and
medial)
spinothalamic tracts and
medial leminscus
(medial=trigeminal nerve) postcentral gyrus somatosensory specific, sensory
Lateral
Geniculate retinal ganglion cells
Lingual and cuneate gyri
of the occipital lobes vision specific, sensory
Medial Geniculate Inferior colliculus auditory cortex auditory specific, sensory
Dorso-
medial
Prefrontal cortex, substantia
nigra, amygdala,
hypothalamus
prefrontal cortex,
amygdala limbic specific, limbic
Pulvinar
primary associational
visual cortex
inferior parietal
cortex (association
cortex)
language
formulation, language
processing
specific,
associational
Centromedian
globus pallidus, vestibular
nucleus, superior colliculus,
reticular formation, spinal
cord, motor / premotor
cortices
basal ganglia and
thalamus
modulates excitability of
cortex (cognitive) and
overall functions of
basal gaglia
(sensorimotor) non-specific
Reticular
thalamocortical
projections
thalamic nuclei and
reticular formation
integrates and regulates
thalamic neuronal
activity non-specific
10. Neuropsychological Syndrome
Analysis a la Luria & Goldberg
⢠Modular and gradiental organization of
neocortical systems
⢠General roles of 1°, 2°, and 3° divisions
â 1° - receptotopic/projectotopic organization; Modality
specificity; Damage leads to modality specific
functional loss (scotoma, anesthesia, acoustic
discrimination)
â 2° - higher order, still modality specific. Categorical
stimulus identification; Recognition of specific
exemplars fo generic categories; Damage leads to
associative "symbolic" agnosias
â 3° - associative, modality non-specific
11. Anterior Gradients: Motor-
Prefrontal
⢠M-1° - Area 4: somatotopic
organization; modality specificity;
damage leads to modality specific
motor loss (paresis)
⢠PM-2° - Area 6, 8 (partial): higher
order, still modality specific.
Lesions lead to disorder of
sequential, kinetic organization of
skilled movements ("melokinetic"
or "limb kinetic" apraxias.
⢠PF-3° - Areas 9, 10, and 8
(partial), 44-47: associative,
modality non-specific.
Supramodal (pervasive)
perseveration, aspontaneity
(intertia of initiation or
termination), field-dependent
behavior, imitative ("echo")
behaviors
12. Consider Broca's aphasia(s):
⢠kinetic speech disturbance
"speech apraxia" (inf.
Premotor, Area 6 )
⢠agrammatism (pars
opercularis, Area 44)
"syntactic agrammatism" -
semantic representation of
action; defects in use of
verbs and action names
⢠dynamic aphasia (pars
triangularis, Area 45) -
impairment in initiation of
communication; thematic
perseveration
13. Tests of Motor and Premotor
Function
⢠Finger Tapping Test, Purdue Pegboard,
Grooved Pegboard, Pin Test
⢠Bimanual Coordination and Dynamic Praxis
(tests for disdiadochokinesis)
⢠Tests of articulatory agility and
buccolingual praxis (e.g., BDAE Oral
Agility subtest)
14. Neuropsychological Testing of
Executive Functions
⢠WM tests
â Manipulation or âworking with memoryâ: Trails B; digits
backwards vs forward; N-back; updating
â Maintenance: ACT, SWM, various exp. tasks
⢠Reasoning/problem solving: Matrices; WCST, Categories,
etc
⢠Generation (word; design)
⢠Tests of response inhibition (Stroop; go-no-go; alternations
ala Luria; Stop-Signal) and reversal
⢠Memory
â Attention/ initial processing vs retrieval; the role of recall vs.
recognition procedures; source memory
15. Tests of Sensitivity to Reward
and Interpersonal Factors
⢠Iowa gambling task (Bechara et al 1994)
â Patients with ventromedial PFC lesions make
bad decisions
â Lack of sensitivity to bad consequences that
usually steer away from actions with bad
outcomes? Lack of âsomatic markersâ?
â âMyopia for the futureâ?
⢠Theory of mind tasks (Frith, others)
16. The Anatomy of Cognitive
Control
⢠The riddle of the frontal lobes
â Once thought to be âsilentâ, lesions produce âno
defect in the intellectâ
â Later seen as the âbiological basis of
intelligenceâ
⢠What do they do?
⢠How do they do it?
17. The Anatomy of Cognitive
Control
⢠Frontal lobe structure-function relations
⢠Frontal projections influence activity throughout
the rest of the brain
â Role in generating âexpectationsâ about the future
â Role in determining the stability and plasticity of
cortical activation states
⢠What can go wrong in frontal function and its
connections, and how this may explain psychosis
18. Frontal Lobe Functional Divisions: The
Dorsal-Ventral Dilemma
⢠Neurologic tradition: dorsolateral vs
orbitofrontal (Benson)
⢠Neuropsychological tradition: dorsomedial,
dorsolateral, orbitofrontal/basal (Luria)
⢠Processing distinctions:
â initiation vs suppression (Fuster)
â what? vs where? (Mishkin/Ungerleider)
â willed intentions vs stimulus intentions (Frith)
19. Dorsal-Ventral Frontal
Distinctions: Another View
⢠Dorsal frontal: hierarchically higher order
modulation of somatomotor effector systems
â Via projections to primary motor cortex, pyramidal
motor system
⢠Ventral frontal: hierarchically higher order
modulation of visceral-autonomic effector systems
â Via projections to anterior temporal, amygdala, and
lateral hypothalamic systems
20. Prefrontal Syndromes
Joaquin Fuster
⢠Dorsolateral (Areas 8, 9, 10, 46)
â Loss of selective and âintensiveâ attention (associated
w/ low drive and awareness), planning problems,
language problems (L)
⢠Orbital (Areas 11, 13)
â Distractibility, utilization behavior, pseudosociopathy
⢠Medial/Cingulate (medial 8-10, 12, 24, 32)
â Apathy, disorders of coordinated movement (cf. Luria
who described âoneiroidâ states)
21. Patricia Goldman-Rakic (dec. 2003)
Definition of highly organized topographically
precise columnar organization of fronto-parietal
projections
23. ⢠DLPFC and working memory ( Nystrom et
al â00))
24. Dual Trends Theory, the Anatomy of
Attention, and Schizophrenia
⢠Anatomic Constraints
â Riddle of the frontal lobes: revisited, again
â Duality of anatomic systems - evolutionary
cytoarchitectonic trends
⢠Functional Significance
â Adaptive resonance architecture and autoregulation
â Attention as an autoregulatory process
⢠Example: Schizophrenia as a disorder of
autoregulation and impairment of cognitive
control
25. Heterogeneity of Frontal Lobe
Structure
⢠Sulco-gyral patterns
⢠Cytoarchitectonic divisions, laminar
organization
⢠Connectional anatomy
⢠Evolutionary (comparative) anatomy
ďDual Trends Theory: Neural systems
solution based on comparative anatomy,
cytoarchitectonics and connectional
anatomy
26.
27. Dual Trends Theory:
History
⢠Dart (1934 - reptiles), Abbie (1940 -
marsupials): suggested dual origins of
cortex
⢠Sanides (1969 - mammals, including
primates): architectonic duality
⢠Pandya and colleagues (1985 - present):
primates - modern architectonic and
connectional anatomy
28. Dual Trends Model: Derivation
and Differentiation
⢠Primordial derivation
â archicortical: âhippocampalâ - dorsal-medial
â paleocortical: âolfactoryâ - ventral-lateral
⢠Architectonic differentiation
â most primitive: allocortex (3 layers)
â more differentiated: periallocortex, proisocortex (4 or 5
layers)
â most differentiated: isocortex (6 layers)
â within isocortex, 1° â 2° â 3°
32. Fronto-Posterior Anatomic Circuits
⢠Every post-Rolandic region maintains organized
projections with a corresponding frontal subregion
(Pandya, Goldman-Rakic)
⢠Duality in posterior sensory systems (archi vs
paleo) is paralleled by duality in frontal effector
systems (archi vs paleo)
⢠Level of differentiation is honored between frontal
and post-Rolandic regions
33. Putting it all togetherâŚ
⢠Connections within and between trends over
fronto-posterior networks forms a neural substrate
for autoregulatory processes
â Within trends (short range): hierarchically organized
re-representations at different levels
â Between trends: archicortical and paleocortical
contributions at similar levels of processing
â Fronto-posterior: sensorimotor contributions to
integrated perception-action cycle
34. Cortico-Cortical Connections Within and
Between Dual Trends
1'2'3' 3'2'1'
1'2'3' 3'2'1'
Short-Range
Within
Long-Range
Within
Between
Archicortical - Dorsal/Medial
Paleocortical - Ventral/Lateral
PosteriorFrontal
35. Fronto-Posterior Resonant Architecture Supports
Adaptive Tuning of Network Function
⢠Frontal - plans, âexpectationsâ
⢠Posterior - stimuli, ârealityâ
⢠Resonance: concordance in targets of
converging projections
⢠Compare Grossberg: Adaptive Resonance
Theory (ART) networks
36. Adapative Resonance Theory (ART 1)
Network Function: Resonance Success
⢠Top down (F2âF1)
= expectation
⢠Bottom up (F1âF2)
= reality
⢠F1 nodes that
represent intersection
of F2 with F1 are
preserved (adaptive
resonance is achieved)
37. Summary of Cortico-Cortical Resonance
⢠Resonant circuits between trends within
each modality and effector system, at
similar levels of processing
⢠Organized feed-forward and feed-back
connections across levels of processing
⢠Enables rapid correction of minor mismatch
between expectation and inputs
⢠Automatic âerror correctionâ and refinement
of input representations based on
expectations (and vice versa)
38. But what if
something truly
unexpected
happens?
The scientific merit of your
application was judged by the review
committee not to be within the upper half
of the applications that it reviewed.
Therefore, the application was not scored.
39. ART â Resonance Failure
⢠If difference between
F1 and F2 is large
(resonance failure)
⢠Then mismatch
signal (A) cannot be
inhibited
⢠This causes âresetâ
of F2
40. Cortico-cortical and cortico-limbic
mechanisms for autoregulation
⢠Cortico-cortical (minor resonance failures)
â cortico-cortical interactions between trends, yields
adjustments to existing activations
â enables smooth transitions between subtly different
activation states
⢠Cortico-limbic (major resonance failures)
â limbic âamplificationâ produces massive cortical
âresetâ
â enables dramatic shifts of activation states
41. Duality in Fronto-Limbic Projections
⢠Cingulate bundle - archicortical
â connects archicortical (dorsal/medial) divisions
of frontal lobes with presubiculum, adjacent
transitional cortex [hippocampocentric]
⢠Uncinate bundle - paleocortical
â connects paleocortical (ventral/lateral, orbital)
divisions of frontal lobes with temporal pole,
amygdala, and entorhinal cortex
[amygdalocentric]
43. Dual Arousal Systems Provide
Autoregulatory Control on âAttentionâ
⢠Dual arousal systems (Routtenberg)
â Reticular activating system (RAS) for phasic
arousal
â Forebrain for tonic activation
⢠Functional duality (Pribram)
â dimension of control: stabile vs labile
â bias: redundancy vs novelty
44. Functional Duality of Architectonic Systems
Archicortical Paleocortical
Response mode Tonic Phasic
Attentional bias Redundancy Novelty
Network effect Stability Plasticity
Intention type Willed Stimulus
Control mode Projectional Responsive
Question What's to be
done?
What is it?
45. Physiological and anatomic distinctions
Archicortical Paleocortical
Physiologic
Response
CNV, TNV Orienting
response
Key forebrain
ganglia
Corpora striatum Amygdala
Frontal system Dorsal, medial
PFC, SMA
Ventral, lateral,
orbital PFC, APA
46. Relations of Anatomic Duality to
Neurotransmitter Systems
⢠Archicortical: regulation of fronto-striatal
system via tonic DA activity (esp. D1)
⢠Paleocortical: regulation of ventral frontal
and âinfralimbicâ systems via phasic DA
(esp. D2), 5HT, and adrenergic
⢠Hippocampal: regulation of mismatch
sensitivity via cholinergic, GABA-ergic,
other peptide modulation?
Bilder 1997; Christensen & Bilder 2000;
Bilder, Volavka, Lachman & Grace 2004
47. Genomic Effects on Neurocognitive
Function: The COMT Story
⢠catechol-O-methyltransferase (COMT), catabolizes DA,
NE, other catechol compounds
⢠Functional polymorphism, Val158
Met in exon III of the
(COMT) gene (codominant)
â Met allele associated with low activity COMT (â DA)
â Val allele associated with high activity COMT (â DA)
⢠Several reports show association of Met allele with better
WCST performance (Egan, Malhotra)
⢠One report links Met allele with more prefrontal activation
using fMRI (â efficiency) (Egan)
48. Adapted from Cooper, Bloom and Roth 1996; Grace, 1997; Bilder et al, 2004
COMT
Tonic DA Pool
MAO
Phasic DA pool
Role of COMT in Regulating
Tonic vs Phasic DA Activity
55. Frontal Lobe
⢠Sources of evidence on FL functions
â Lesion/head injury studies
â Unit recordings in monkeys (mostly delayed
match to sample; WM studies
â Activation studies in Humans
56. Pathways
⢠Dorsal pathway: parietal-DLPFC
connections
⢠Ventral pathway: OFC as :primary
projection site of the limbic system (W.
Nauta)
57. Lesion studies
⢠Head injuries (TBI) common source
⢠Syndromes and deficits; likely anatomical
correlates : orbital pathway
â Arousal changes: Adynamia or agitation:
â Likely due to orbital frontal damage, usually extensive.
â ACA territory lesions and adynamia
â Low motivation; decreased initiative: Probable loss of reward/motivation
due to decreased striatal input
â Reduced insight. Concept of âtheory of mindâ recent data on role of
anterior medial frontal gyrus in TOM, may underlie deficits in insight.
â Control of attention and selection in anterior cingulate damage.
â Reduced impulse control; deficits in response inhibition in OF lesions
58. Syndromes and deficits; likely anatomical correlates :
Dorsal pathway
â Eye motor control deficits: Frontal Eye fields direct EM based on spatial
information from PL
â Working memory impairment: Lesions in DLPFC ; also single unit studies
in monkey PFC; delayed component; manipulation component; response
selection component
â Reasoning, problem solving deficits; poor âfluidâ reasoning
⢠Integration of information
â Perseveration: 46/44 direct stimulation produces perseveration deficits
⢠Appears separate from WM
â Memory retrieval deficits
⢠Probable anterior, BA 10 contribution to active search/retrieval
from LTM; probable RH contribution
⢠HERA model (Heispheric encoding/rectrieval asymmetry;
found in verbal memory tasks: LH active during learning of
new (verbal) memories; RH active during retrieval
59. Neuropsychological Testing of
Executive Functions
⢠WM tests (Trails B; digits backwards vs forward;
N-back, etc)
⢠Reasoning/problem solving: Matrices; WCST,
Categories, etc
⢠Generation (word; design)
⢠Tests of response inhibition (Stroop; go-no-go;
alternations ala Luria
⢠Memory
â Attention/ initial processing vs retrieval; the role of
recall vs. recognition procedures.
60. Frontal Lobe
⢠Sources of evidence on FL functions
â Lesion/head injury studies
â Unit recordings in monkeys (mostly delayed
match to sample; WM studies
â Activation studies in Humans
61. Pathways
⢠Dorsal pathway: parietal-DLPFC
connections
⢠Ventral pathway: OFC as :primary
projection site of the limbic system (W.
Nauta)
62. Lesion studies
⢠Head injuries (TBI) common source
⢠Syndromes and deficits; likely anatomical
correlates : orbital pathway
â Arousal changes: Adynamia or agitation:
â Likely due to orbital frontal damage, usually extensive.
â ACA territory lesions and adynamia
â Low motivation; decreased initiative: Probable loss of reward/motivation
due to decreased striatal input
â Reduced insight. Concept of âtheory of mindâ recent data on role of
anterior medial frontal gyrus in TOM, may underlie deficits in insight.
â Control of attention and selection in anterior cingulate damage.
â Reduced impulse control; deficits in response inhibition in OF lesions
63. Syndromes and deficits; likely anatomical correlates :
Dorsal pathway
â Eye motor control deficits: Frontal Eye fields direct EM based on spatial
information from PL
â Working memory impairment: Lesions in DLPFC ; also single unit studies
in monkey PFC; delayed component; manipulation component; response
selection component
â Reasoning, problem solving deficits; poor âfluidâ reasoning
⢠Integration of information
â Perseveration: 46/44 direct stimulation produces perseveration deficits
⢠Appears separate from WM
â Memory retrieval deficits
⢠Probable anterior, BA 10 contribution to active search/retrieval
from LTM; probable RH contribution
⢠HERA model (Heispheric encoding/rectrieval asymmetry;
found in verbal memory tasks: LH active during learning of
new (verbal) memories; RH active during retrieval
64. Neuropsychological Testing of
Executive Functions
⢠WM tests (Trails B; digits backwards vs forward;
N-back, etc)
⢠Reasoning/problem solving: Matrices; WCST,
Categories, etc
⢠Generation (word; design)
⢠Tests of response inhibition (Stroop; go-no-go;
alternations ala Luria
⢠Memory
â Attention/ initial processing vs retrieval; the role of
recall vs. recognition procedures.
65. ⢠DLPFC and working memory ( Nystrom et
al â00))
69. Copyright Š2006 Society for Neuroscience
Aron, A. R. et al. J. Neurosci. 2006;26:2424-2433
Figure 1. A basal-ganglia model and the Stop-signal paradigm
70. Copyright Š2006 Society for Neuroscience
Aron, A. R. et al. J. Neurosci. 2006;26:2424-2433
Figure 2. Activated networks for Going and Stopping and key peristimulus time courses for
the hemodynamic response
71. Copyright Š2006 Society for Neuroscience
Aron, A. R. et al. J. Neurosci. 2006;26:2424-2433
Figure 3. ROI analyses for experiment 1
76. 1. Generic Psychology Core
A.      Statistics and methodology
B.      Learning, cognition and perception
C.      Social psychology and personality
D.      Biological basis of behavior
E.       Life span development
F.       History
G.      Cultural and individual differences
and diversity
Houston Guidelines for Training in
Clinical Neuropsychology
77. Houston Guidelines for Training in
Clinical Neuropsychology
2. Generic Clinical Core
A.      Psychopathology
B.      Psychometric theory
C.      Interview and assessment
techniques
D.      Intervention techniques
E.       Professional ethics
78. Houston Guidelines for Training in
Clinical Neuropsychology
3. Foundations for the study of brain-behavior
relationships
A.      Functional neuroanatomy
B.      Neurological and related disorders
C.      Non-neurologic conditions affecting
CNS functioning
D.      Neuroimaging and other
neurodiagnostic techniques
E.       Neurochemistry of behavior (e.g.,
psychopharmacology)
F.       Neuropsychology of behavior
79. Houston Guidelines for Training in
Clinical Neuropsychology
4. Foundations for the practice of clinical
neuropsychology
A.      Specialized neuropsychological
assessment techniques
B.      Specialized neuropsychological
intervention techniques
C.      Research design and analysis in
neuropsychology
D.      Professional issues and ethics in
neuropsychology
E.       Practical implications of
neuropsychological conditions
80. Houston Guidelines for Training in
Clinical Neuropsychology
VII. Skills.
1.       Assessment
o        Information gathering
o        History taking
o        Selection of tests and measures
o        Administration of tests and measures
o        Interpretation and diagnosis
o        Treatment planning
o        Report writing
o        Provision of feedback
o        Recognition of multicultural issues
81. Houston Guidelines for Training in
Clinical Neuropsychology
2.       Treatment and Interventions
o        Identification of intervention targets
o        Specification of intervention needs
o        Formulation of an intervention plan
o        Implementation of the plan
o        Monitoring and adjustment to the
plan as needed
o        Assessment of the outcome
o        Recognition of multicultural issues
82. Houston Guidelines for Training in
Clinical Neuropsychology
3.       Consultation (patients, families, medical
colleagues, agencies, etc.)
o        Effective basic communication
o        Determination and clarification of
referral issues
o        Education of referral sources
o        Communication of evaluation results
and recommendations
o        Education of patients and families
83. Houston Guidelines for Training in
Clinical Neuropsychology
4.       Research
o        Selection of appropriate research
topics
o        Review of relevant literature
o        Design of research
o        Execution of research
o        Monitoring of progress
o        Evaluation of outcome
o        Communication of results
84. Houston Guidelines for Training in
Clinical Neuropsychology
5.       Teaching and Supervision
o        Methods of effective teaching
o        Plan and design of courses and
curriculums
o        Use of effective educational
technologies
o        Use of effective supervision
methodologies
94. Prefrontal Disorders
Joaquin Fuster
⢠Planning
⢠Intelligence
⢠Temporal integration
⢠Language
⢠Affect and emotion
â Apathy, depression, euphoria, social and
emotional behavior
Editor's Notes
Old functinal distinctions based on lesion data, suggesting division of pseudodepressed vs pseudopsychopathic states,
and NP studies, separating out oneiroid states (medial) from inertia/apathy syndromes, and disinhibitory pathology
More recent work has focused on dualities:
- initiation vs suppression -
- what vs where, derived from posterior visual stream data, spatial vs object
- willed intentions vs stimulus intentions - albeit not specific about anatomy (probably wise)
Can we superimpose these functional distinctions on specific anatomic constructs? Mapping question.
Range of approaches -
sulcogyral - crude approximations
cytoarchitectonic divisions - may map more closely on functional systems?
Connectional anatomy - complements cytoarchitectonic approach
Evolutionary - discerns basic principles of organization by mapping homologies back to simpler species
Developmental (Pasko-Rakic) still a lot of work to be done
Molecular biology - growth genes, alsopatterns of gene expression
Dual trends theory - focuses on Cyto, Connect, and Evolutionary
Here I discuss the primary projections into FL. Dorsal pathway- primarily receives input from posterior cortices vis parietal lobe, including visual and auditory info. Strongest conenctions with IPS tissue- WM loop; also discuss phonological loop into Ifjunction from SMG.
Ventral pathway- limbic input especiall discuss HC and Amygdala; also discuss olfaction and the reason so many TBIs cant smell. You might want to add striatal pathways here.
Robert- here I use numerous examples from my own experience with patients. I describe each one in detail and the likely anatomy.
Here I discuss the primary projections into FL. Dorsal pathway- primarily receives input from posterior cortices vis parietal lobe, including visual and auditory info. Strongest conenctions with IPS tissue- WM loop; also discuss phonological loop into Ifjunction from SMG.
Ventral pathway- limbic input especiall discuss HC and Amygdala; also discuss olfaction and the reason so many TBIs cant smell. You might want to add striatal pathways here.
Robert- here I use numerous examples from my own experience with patients. I describe each one in detail and the likely anatomy.
Seeing scary things (including faces with negative affect) produces increased activity in the amygdala; Applying a verbal label has the effect of reducing amygdala activity and increasing ventral PFC activity. Here the subjects label the scene as natural or artificial; compared to E on the left, the brain shows increased activity in VPFC.
Here the authors show medial prefrontal and DLPFC active for stroop inhibition, but anterior OFC active during motor inhibition
Figure 1. A basal-ganglia model and the Stop-signal paradigm. A, An influential model proposes three pathways through the basal ganglia (direct, indirect, and hyperdirect). SNr, Substantia nigra; THAL, thalamus; STR, striatum. Open arrows are excitatory (glutamatergic); filled arrows are inhibitory (GABAergic). Figure adapted from Nambu et al. (2002). B, The Stop-signal paradigm consists of Go- and Stop-signal trials. On Go trials, the subject has 1 s (the hold period) to make a left or right button press in response to the stimulus. As soon as the subject responds (reaction time), the stimulus is replaced by a blank screen for a variable period of time (1 s â RT = jitter time, where jitter ranges between 0.5 and 4 s, mean of 1 s). On a Stop trial, a tone is played at some delay (SSD) after the arrow stimulus. If the response is inhibited, the arrow remains for 1 s, followed by the blank screen jitter period; if the subject does not inhibit (i.e., responds), then the timing is the same as the Go trial. SSD changes dynamically throughout the experiment to produce a 50% inhibition rate (see Materials and Methods). C, SSRT is estimated using the race model (Logan and Cowan, 1984). This assumes that Go and Stop processes are in a race and are independent of each other. The independence assumption implies that the distribution of Go processes on Stop trials (whether a response is made or not) is the same as the observed distribution of Go responses (when there is no Stop signal). On Stop trials, a tone occurs at some delay, the SSD after the Stop signal. If this delay is short, then P(inhibit) is high and this is likely to be a StopInhibit trial; if the delay is long, then P(inhibit) is low and this is likely to be a StopRespond trial. If SSD is varied so that P(inhibit)=0.5, then SSRT can be estimated by subtracting the SSD from the median value of the Go distribution.
Figure 2. Activated networks for Going and Stopping and key peristimulus time courses for the hemodynamic response. Images are in neurological format (right = right). Activations are overlaid on coronal slices from the SPM single-subject structural template. All maps are thresholded at t > 3.05 voxel level, p < 0.05 cluster corrected for whole brain. A, Go trials activate contralateral motor cortex (M1), SMA, bilateral putamen (PUT), and left thalamus/pallidum, consistent with a fronto-striatal pathway. B, StopInhibit trials activate auditory cortex, parietal cortex, right STN, medial frontal cortex, bilateral putamen, and bilateral orbital/insula cortex extending into the opercular IFC in the right hemisphere. These activations include those associated with preparing to execute a Go response as well as the response inhibition network revealed, more precisely, by the contrast of StopInhibitâGo (C). This network includes right-lateralized STN, IFC, GP, and pre-SMA (also shown on saggital and surface rendered images). This network is also activated on StopRespond trials (D). E, StopInhibit trials activate bilateral putamen more than StopRespond, but this is not the case for StopRespondâGoTrim (F), which contrasts trials on which the subject tried to stop, but could not, with trials on the which the subject did not try, while controlling for response speed. On the right of the figure are shown peristimulus plots (with SEs) for different trial types for key foci. For these, mean activation for each subject was extracted from a sphere (radius, 4 mm) centered on the peak group-activated voxel. Note the differential effects of Go, StopInhibit, and StopRespond on the time course of the estimated BOLD response in left motor cortex in particular (inset, top right): StopInhibit trials have a delayed response, whereas StopRespond trials peak at the same time and amplitude as Go trials but then show a strong undershoot as if the inhibition occurred too late. Surface rendering for the lateral view was created by mapping the group-averaged fMRI data into a population-averaged surface atlas using multifiducial mapping (Van Essen, 2005). Thal, Thalamus; acc, anterior cingulate cortex; ctx, cortex.
Figure 3. ROI analyses for experiment 1. B, StopInhibitâGo activation shown overlaid on anatomically defined IFC, pre-SMA, GP, and STN ROIs. The ROIs are color-coded. IFC pre-SMA and GP were defined from the AAL template (Tzourio-Mazoyer et al., 2002) and the STN according to the atlas by Lucerna et al. (2002). Activation is significant p < 0.05 corrected for whole-brain multiple comparisons. A, The response inhibition network made up of IFC, pre-SMA, GP, and STN is significantly more active in the right than left hemisphere. For each subject, the mean value for all voxels in each anatomically defined ROI was computed for the contrast of StopInhibitâGo. All ROIs (except GP) showed significantly greater activation in the right hemisphere than the left (all p < 0.005; Bonferroniâs corrected). C, Across subjects, mean activation in right STN and right IFC was significantly correlated (for StopInhibitâGo contrast). D, E, Subjects who inhibit more quickly activate right IFC and STN more. StopInhibitâGo activation is significantly greater for subjects with fast SSRT versus those with slow SSRT (independent samples t test) in right IFC (MNI: 42, 26, 14; t = 7.26; p = 0.005, SVC) and right STN (MNI: 8, â20, â4; t = 3.48; p = 0.051, SVC). F, When inhibition occurs later, STN is more active. For StopInhibitâGo, activation in right STN increases parametrically with increasing SSD (MNI: 6, â18, â2; t = 3.42; p = 0.028, one-tailed, SVC). The y coordinate in MNI space is shown above each coronal slice. The color scale represents t score. R, Right.
Shows role of BA 10 in retrieval
Here the authors show medial prefrontal and DLPFC active for stroop inhibition, but anterior OFC active during motor inhibition
Seeing scary things (including faces with negative affect) produces increased activity in the amygdala; Applying a verbal label has the effect of reducing amygdala activity and increasing ventral PFC activity. Here the subjects label the scene as natural or artificial; compared to E on the left, the brain shows increased activity in VPFC.