functional neuroanatomy

Functional neuroanatomy

bradd@nmr.mgh.harvard.edu

• Overview of brain anatomy & systems– Localization/networks– Scale in the nervous system– Sensorimotor systems

• How our brains interact with the external world (loops)– States ‘of mind’ (and body)

• Specific functional systems– Memory & emotion

• How our brains use previous experience to modify behavior

– Language; visual processing; mental imagery• How our brains integrate types of information to develop concepts;

how previous experience affects processing of new information

Localization of function in the nervous system: Maps and networks

Localization of function in the nervous system: Functional networks

5 major brain systems subserving

cognition and behaviorLeft perisylvian language networkParieto-frontal network for spatial attentionOccipitotemporal network for object/face recognitionMedial temporal/limbic network for learning & memoryPrefrontal network for attention & comportment

5 types of cortical tissue

Plasticity in heteromodal cortical regions: The basis for learning

Lesion studies of the language network:The major nodes

Broca’s (production) Wernicke’s (comprehension)

Lesion studies of the language network:Disconnection syndromes

Alexia without agraphia

Geschwind N & Kaplan E, Neurology, 1962

Functional neuroimaging of the language network

One to many, many to oneCJ Price, J Anat 2002

Language function: Using neuroimaging to test hypotheses

CJ Price, J Anat 2002

Language function in the bilingual brain

Kim KHS, Nature 1997

Recovery of language function after stroke: Mapping plasticity in the human brain

Fernandez B, Stroke 2004

1 year after stroke

1 month after stroke

Plasticity: Many levels of scale in both time & space

What’s in a name?A means to access specific types of

knowledge

What’s in a name?A means to access specific types of

knowledge

Elephant

Linguistic access to specific types of knowledge

Damasio H, Nature 1996

Visual processing: Two pathwaysDorsal (Occipito-parietal): Object & object feature recognition

Disorders:

visual object agnosia

prosopagnosia

achromatopsia

Ventral (Occipito-temporal): Visual recognition of spatial location

Disorders: optic ataxia, ocular apraxia, simultanagnosia (Balint’s); constructional apraxia, akinotopsia

Visual processing streams: Confirmation of hypotheses using neuroimaging

Ungerleider LG, PNAS 1998

Visual processing: Attention influences which stream is used

Ungerleider LG, PNAS 1998

Visual object recognition: Lesion studies

Agnosias may be specific to certain categories of information

Visual object recognition: Distinct but overlapping functional areas

Haxby JV, Science 2001

Visual imagery & neuroimaging

Ganis G, Cog Brain Res 2004

Auditory imagery & neuroimaging

Kosslyn SM, Nat Rev Nsci 2001

Visual imagery & neuroimaging

Kosslyn SM, Nat Rev Nsci 2001

Visual memory may influence perception: The v17 controversy in imagery

Kosslyn SM, Nat Rev Nsci 2001Correlation vs. causality

Naming vs. recognition: Networks for conceptual knowledge

Name this animal and tell me what you know about it

Naming vs. recognition: Networks for conceptual knowledge

Name this person and tell me what you know about him

Naming vs. recognition: Networks for conceptual knowledge

Damasio H, Cognition 2004

Object-specific naming deficits Object-specific recognition deficits

Heteromodal processing

The limbic system directs heteromodal cortex toward relevant information

LaBar KS, Behavioral Neuroscience 2001

Visual object recognition: Binding together perception, memory, emotion,

and motivation

Leibenluft E, Biol Psych 2004

Amygdala Insula

Cingulate Sup temp

What happens when a mother recognizes her child’s face?

What are we doing with our brains at this moment?

(The student’s brain)

• Feeling your chair• Squirming (moving)• Watching• Listening• Remembering• Paying attention• Sleeping• Feeling anxious• Feeling hungry• What happens when you ask a question?