Central Nervous System PowerPoint

WHS AP Psychology

Unit 3: Biological Psychology Essential Task 3-5a.Describe the subdivisions and functions of the Central Nervous System A. Brain i. Brain Stem Medulla, Pons, Reticular Formation, Cerebellum, and the Thalamus ii. Limbic System Hypothalamus, Amygdala, and the Hippocampus iii. Cerebral Cortex (Left and Right Hemispheres and the corpus callosum) Occipital Lobe, Parietal Lobe, Temporal Lobe, and the Frontal Lobe Primary Motor Cortex and Primary Sensory Cortex Wernicke's Area and Broca's Area B. Spinal Cord

We are Evolutionary here

Endocrine System Building Blocks

Biological Psychology

Genetics

Neurons

Nervous System

Central Nervous System

Peripheral Nervous System Motor

Brain

Brain Imaging

Spinal Cord

Autonomic

Sympathetic

Neurotransmitters

Sensory

Somatic

Parasympathetic

Essential Task 3-5: CNS Outline A. Brain i. Brain Stem Medulla, Pons, Reticular Formation, Cerebellum, and the Thalamus ii. Limbic System Hypothalamus, Amygdala, and the Hippocampus iii. Cerebral Cortex (Left and Right Hemispheres and the corpus callosum) Occipital Lobe, Parietal Lobe, Temporal Lobe, and the Frontal Lobe Primary Motor Cortex and Primary Sensory Cortex Wernicke's Area and Broca's Area B. Spinal Cord

The Brain Stem (Automatic Functions) Brain Structure

Primary Function

Secondary Function

Medulla

Respiration, blood pressure, heart rate

Vomiting

Pons

Puts you to sleep

Reticular Formation

Attention, regulates awareness

Cerebellum

Balance and coordination

Thalamus

Directs sensory information to the rest of the brain

Older Brain Structures The Brainstem is the oldest part of the brain, beginning where the spinal cord swells and enters the skull. It is responsible for automatic survival functions.

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Brain Stem The Medulla [muh-DULuh] is the base of the brainstem It controls autonomic functions and relays nerve signals between the brain and spinal cord. •respiration •blood pressure •heart rate •reflex arcs •vomiting 7

Brain Stem Pons and inside that the (Reticular Formation) is a nerve network in the brainstem that plays an important role in controlling arousal. •It is involved in motor control and sensory analysis... for example, information from the ear first enters the brain in the pons. It has parts that are important for the level of consciousness and for sleep. The Reticular Formation controls: •Attention •Cardiac Reflexes •Motor Functions •Regulates Awareness •Relays Nerve Signals to the Cerebral Cortex •Sleep

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Brain Stem The Medulla [muhDUL-uh] is the base of the brainstem that controls heartbeat and breathing. Reticular Formation is a nerve network in the brainstem that plays an important role in controlling arousal. 9

Brain Stem The Thalamus [THALuh-muss] is the brain’s sensory switchboard, located on top of the brainstem. It directs messages to the sensory areas in the cortex and transmits replies to the cerebellum and medulla. 10

Cerebellum

The “little brain” attached to the rear of the brainstem. It helps coordinate voluntary movements and balance. 11

Limbic System (Emotion Center) Brain Structure

Primary Function

Secondary Function

Hypothalamus

Drives: Hunger, Thirst, Sex

Temperature control

Amygdala

Fight or Flight

Hippocampus

STM to LTM

The Limbic System The Limbic System is a doughnut-shaped system of neural structures at the border of the brainstem and cerebrum, associated with emotions such as fear, aggression and drives for food and sex. It includes the hippocampus, amygdala, and hypothalamus. 13

Amygdala The Amygdala [ah-MIGdah-la] consists of two almond-shaped neural clusters linked to the emotions of fear and anger.

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Hypothalamus The Hypothalamus lies below (hypo) the thalamus. It directs several maintenance activities like eating, drinking, body temperature, and control of emotions. It helps govern the endocrine system via the pituitary gland. 15

Reward Center

Sanjiv Talwar, SUNY Downstate

Rats cross an electrified grid for self-stimulation when electrodes are placed in the reward (hypothalamus) center (top picture). When the limbic system is manipulated, a rat will navigate fields or climb up a tree (bottom picture). 16

Cerebral Cortex Brain Structure

Primary Function

Occipital Lobe

Visual Processing

Parietal Lobe

Spatial Reasoning

Frontal Lobe Temporal Lobe

Decision Making Auditory sensory information

Motor Cortex

Movement

Sensory Cortex

Sensation

Wernicke’s Area

Understanding Speech

Broca’s Area

Producing Speech

Secondary Function

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

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Structure of the Cortex Each brain hemisphere is divided into four lobes that are separated by prominent fissures. These lobes are the frontal lobe (forehead), parietal lobe (top to rear head), occipital lobe (back head) and temporal lobe (side of head).

Functions of the Cortex The Motor Cortex is the area at the rear of the frontal lobes that control voluntary movements. The Sensory Cortex (parietal cortex) receives information from skin surface and sense organs.

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Visual Function The functional MRI scan shows the visual cortex is active as the subject looks at faces.

Auditory Function The functional MRI scan shows the auditory cortex is active in patients who hallucinate.

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

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Language Aphasia is an impairment of language, usually caused by left hemisphere damage either to Broca’s area (impaired speaking) or to Wernicke’s area (impaired understanding).

Specialization & Integration Brain activity when hearing, seeing, and speaking words

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Can you make a purple circle with a cross in the middle?

Fun with your Hemispheres • Rotate your dominant hand in one direction while at the same time rotating the opposite foot in the other direction. – No problem since controlled by two hemispheres

• Now, rotate your dominant hand in one direction while at the same time rotating the foot on the same side in the other direction.

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Our Divided Brain Our brain is divided into two hemispheres. The left hemisphere processes reading, writing, speaking, mathematics, and comprehension skills. In the 1960s, it was termed as the dominant brain.

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Hemispheric Specialization • Corpus Callosum – Fibers that connect the two hemispheres – Allow close communication between left and right hemisphere

• Each hemisphere appears to specialize in certain functions • (See Worksheet)

The Wagner Preference Inventory • (a) left, logical • (b) left, verbal • (c) right, manipulative/spatial • (d) right, creative

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Hemispheric Specialization People with intact brains also show leftright hemispheric differences in mental abilities. A number of brain scan studies show normal individuals engage their right brain when completing a perceptual task and their left brain when carrying out a linguistic task.

Splitting the Brain A procedure in which the two hemispheres of the brain are isolated by cutting the connecting fibers (mainly those of the corpus callosum) between them. Corpus Callosum

Split Brain Patients With the corpus callosum severed, objects (apple) presented in the right visual field can be named. Objects (pencil) in the left visual field cannot.

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Divided Consciousness

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The Spinal Cord • Complex cable of nerves that connects brain to rest of the body • Carries motor impulses from the brain to internal organs and muscles • Carries sensory information from extremities and internal organs to the brain • 400,000 people a year in US either partial or complete paralysis.

The Spinal Cord • The spinal cord controls some protective reflex movements without any input from the brain