Cerebral Cortex

Lecture 4

1 Functional Specialization So Far

• and Nerves • – Afferent, Efferent, – Hindbrain Interneurons • , Medulla, • Peripheral Nervous Cerebellum System – • Reticular Formation – Autonomic – Forebrain Subcortical • Sympathetic, Structures Parasympathetic • Hypothalamus – Somatic • Hippocampus • Afferent, Efferent • Pathways

2 Topography of Telencephalon Lateral View

Medial View

3 Locating Yourself in the Brain

4 Folds in Cerebral Cortex

• (Gyri) •Inferior Frontal •Superior Temporal • (Sulci) • •Parieto-Occipital •Pre-Occipital Notch

5 Cytoarchitectonics of the Cerebral Cortex Brodmann (1909)

6 Primary Motor and Somatosensory Areas •Primary • • 4 • •Brodmann Area 6 • • •Brodmann Areas 1-3

7 Consequences of Stroke Insufficient Blood Supply to Brain

• Paralysis – voluntary motor function • Anesthesia – tactile sensation • – speech, language

8 Sensory and Motor Homunculus Penfield & Jasper (1954)

Parietal Lobe

Longitudinal Fissure

Central Fissure

Lateral Fissure Scientific American 11/79

9 Primary Auditory and Visual Areas

•Primary • •Heschl’s Gyrus (AI) •Brodmann Areas 41, 42 •“Tonotopic” Organization •Primary •Striate Cortex (VI) •Brodmann Area 17 •“Retinotopic” Organization • •Brodmann’s Areas 18, 19 10 Specialization in Extra-Striate Cortex

11 “Association Areas”

• Posterior – Perceptual Integration • Frontal – Executive Functions – Problem-solving • “Prefrontal” Cortex – Frontal Gyri • Superior, Middle, Inferior – Frontal Sulci • Superior, Inferior

12 Some Common Neurological Symptoms

Amnesia () Aphasia (Speech) Alexia (Reading) Agraphia (Writing) Acalculia (Math) Apraxia (Action) (Knowledge)

13 Major of Aphasia • Broca’s Aphasia: “Expressive” – Slow, Labored, Inarticulate Speech • Possible Problems with Writing, Reading Aloud – Speech Comprehensible – No Problems Understanding Speech, Reading • Wernicke’s Aphasia: “Receptive” – Fluent (Phonetics, Grammar) – Paraphasias – Semantic Deviance

– Problems Understanding Speech, Writing 14 Language Centers in the Brain

Scientific American 15 Coordination of Language Functions Petersen et al. (1988, 1989)

Scientific American

16 Electrocorticogram of Verb Generation Edwards et al. (2007, 2010)

Motor Cortex

fMRI Wernicke’s Broca’s Area Area

Courtesy of R.T. Knight 17 Recognition in the

• Prosopagnosia – Bodamer (1947) – Brodmann Area 37 • Also Areas 18, 19 • fMRI in Face Recognition • “” (?)

18 Self-Regulation in the Anterior Cingulate Gyrus

• Part of – Anterior • “ACC” • Executive Functions – Controlled Processing • Self-Regulation – Error Detection – Conflict Monitoring

19 The Parietal Cortex and Attention

• – Contralateral Typical performance by a “neglect” patient on the line-bisection task •

20 Imaging the Stage Model of Attention Fan et al. (2005), after Posner & Peterson (1990)

• Alerting and Interruption – Fronto-Parietal – • Orienting and Localizing – Superior Parietal • Executive Control – Anterior Cingulate Gyrus – Frontal • Disengage • Move (Shift) • (Re-) Engage • Inhibit 21 Old and New Views of Specialization

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