The Brain

Parts of the Brain Brainstem the oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; the “primitive” brain responsible for automatic survival functions

The Brain – Parts of the Brainstem Thalamus [THAL-uh-muss] the brain’s sensory switchboard, located on top of the brainstem it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla Reticular Formation a nerve network in the brainstem that plays an important role in controlling arousal Medulla [muh-DUL-uh] base of the brainstem controls heartbeat and breathing

Parts of the Brain Cerebellum [sehr-uh-BELL-um] the “little brain” attached to the rear of the brainstem it helps coordinate voluntary movement and balance

Parts of the Brain Limbic System a doughnut-shaped system of neural structures at the border of the brainstem and cerebral hemispheres associated with emotions such as fear and aggression and drives such as those for food

The Brain – Parts of the Limbic System Amygdala [ah-MIG-dah-la] two almond-shaped neural clusters that are components of the limbic system and are linked to emotion and memory Hippocampus Linked to long and short term memory and emotion.

The Brain – Parts of the Limbic System Hypothalamus neural structure lying below (hypo) the thalamus directs several maintenance activities eating drinking body temperature

The Brain – Parts of the Limbic System Hypothalamus (cont) helps govern the endocrine (hormones) system via the pituitary gland growth and development, metabolism, tissue function, etc is linked to emotion and mood

The Limbic System – An Experiment Electrode implanted in reward center What do you think the rat will do?

The Cerebral Cortex Cerebral Cortex the intricate fabric of interconnected neural cells that covers the cerebral hemispheres the body’s ultimate control and information processing center

Parts of the Cerebral Cortex

Parts of the Cerebral Cortex Frontal Lobes the “star” of the brain - involved in speaking and muscle movements, making plans and judgments, reasoning, impulse control Parietal Lobes include the sensory cortex – sensory integration

Parts of the Cerebral Cortex

Parts of the Cerebral Cortex Occipital Lobes include the visual areas, which receive visual information from the opposite visual field Temporal Lobes auditory perception, categorization, essential for social interaction

Parts of the Cerebral Cortex

Parts of the Cerebral Cortex Motor Cortex area at the rear of the frontal lobes controls voluntary movements Sensory Cortex area at the front of the parietal lobes registers and processes body sensations

Parts of the Cerebral Cortex

Parts of the Cerebral Cortex Functional MRI scan shows the visual cortex activated as the subject looks at faces Visual and Auditory Cortex

Parts of the Cerebral Cortex Association Areas More intelligent animals have increased “uncommitted” or association areas of the cortex

Cerebral Cortex Specialization and Integration The brain uses many parts at once i.e. Language functioning when reading and speaking Click picture to watch about animal “language”

Cerebral Cortex - Specialization and Integration Aphasia impairment in the ability to use or comprehend words Signs: Understanding words. Finding the word to express a thought Understanding grammatical sentences. Reading or writing words or sentences. usually caused by left hemisphere damage Wernicke’s Area an area of the left temporal lobe involved in language comprehension and expression

Cerebral Cortex - Specialization and Integration Apraxia difficulty initiating and executing voluntary movement patterns necessary to produce speech when there is no paralysis or weakness of speech muscles. Signs: Producing the desired speech sound. Using the correct rhythm and rate of speaking. usually caused by left hemisphere damage Broca’s Area an area of the left frontal lobe that directs the muscle movements involved in speech

Cerebral Cortex - Specialization and Integration Brain activity when hearing, seeing, and speaking words

Cerebral Cortex - Brain Reorganization Plasticity the brain’s capacity for modification brain reorganization following damage (especially in children) in the effects of experience on brain development

Cerebral Cortex - Brain Reorganization Experiment Some rats are housed alone in empty cages Their littermate twins are group-housed in cages with toys, which are changed frequently Richer environments led to heavier, thicker brains, more synapses, and better learning Figure 2.06 from Morris, C.G., & Maisto, A.A. (1999). Psychology, 10th Edition. Upper Saddle River, NJ: Prentice Hall. Source: Rosenzweig, M..R., Bennett, E.L., & Diamond, M.C. (1972). Scientific American, See also: Renner, M. J., & Rosenzweig, M.R. (1987). Enriched and Impoverished Environments: Effects on Brain and Behavior. New York: Springer Verlag.

Our Divided Brain – The Two Hemispheres Left Hemisphere Verbal Math Analytic Right Hemisphere Spatial Holistic Nonverbal Corpus Callosum Large band of neural fibers Connects the two hemispheres Carries messages back and forth Corpus callosum

Our Divided Brain – Visual Field The information highway from the eye to the brain http://www.youtube.com/watch?v=MZnyQewsB_Y

Our Divided Brain - Split Brain a condition in which the two hemispheres of the brain are isolated by cutting the connecting fibers (mainly those of the corpus callosum) between them

Our Divided Brain - Split Brain

Our Divided Brain - Split Brain