Brain and behavior - Lecture notes 1 PDF

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this is about the brain and how it affects your behavior....

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Brain and behavior  Brain is responsible for how you feel  The central nervous system o Brain and spinal cord  The peripheral nervous system o The somatic and autonomic nervous system  The autonomic nervous system o The sympathetic and parasympathetic nervous system  Somatic NS: network linking the spinal cord and with the body  Autonomic NS: carries information to and from internal organs and glands. Monitors processes like breathing, heart rate, and digestion. o Sympathetic: arouses the body (fight or flight) Parasympathetic: quiets the body and conserves energy (rest) (dearouse) Neuron Structure Neurons have four basic parts: 1. Cell body: contains nucleus: decides whether to send the message onward. 2. Dendrites: along with the cell body, receives incoming messages 3. Axon: carries information away 4. Axon terminal: a bulb shaped structure at the end of each axon Neurons: a cell in the nervous system that transmits information Nerve: A bundle of neuron axons Neural Function- Resting Potential  Neural functions are primarily electrical. Neurons are essentially little batteries!  Ions: electrically charged molecules found both inside and outside the neuron; either positively or negitively charged.  AN inactive neuron ("resting") has more negative ions inside and more positive neurons outside

 Resting potential: the electrical charge of an inactive neuron.  If enough "exciting" messages arrive close enough to each other, the resting neuron reaches its threshold ( the minimum charge required for firing) also called action potential  After the action potential, the neuron rests for a brief moment before being recharged for the next one.  Neurotransmitters: the chemical messages being moved from one neuron to the next.  Reflex arc: the simplest behavior, in which a stimulus provokes an automatic response. o Sensory neuron: transmits information from the sense organs to the CNS, which then alerts the spinal cord of the stimulus. o Motor neuron: transmits commands from the CNS back to the muscles  Neuroplasticity: the capacity of the brain to change in response to experiences  Repeated activation of synapses between neurons is thought to strengthen their connection, making sending and receiving a particular message easier.  Brains are thought to "rewire" themselves to weaken or kill unused synaptic connections and produce new, stronger ones in response to what our environment and tasks call for.  Neurogenesis: the production of new brain cells o Thousands of new cells can link up to the neural network every day.  Computed tomographic (CT) scan: a computer collects X-rays from multiple angles to create an image. o Reveals brain structure and the location of strokes, injuries, tumors, and other abnormalities  Magnetic resonance imaging (MRI) scan: results in a 3D image of the brain or body by exposing it to a strong magnetic field. o More detailed than CT X-rays, without the radioactive exposure.

 Localization of function: linking specific structures in the brain to specific functions.  Deep lesioning: researchers cause intentional damage to a specific area of the brain below the surface to study changes it causes t functions/behavior.  Ablation: removal of an area of the surface of the brain  Electrical stimulation of the brain (ESB): a mild electrical current is delivered through an electrode; used to stimulate a specific area so the patient can describe its effects.  Electroencephalograph (EEG): amplifies brain waves  Position emission tomography (PET): captures brain activity by attaching radioactive particles to glucose molecules  Functional MRI: uses MRI technology to record activity levels

 Cerebral cortex: thin outer covering of the brain in which high-level processes take place  Cerebral hemispheres: the left and right sides of the CC o Corpus callosum: a thick band of axon fibers connecting the two sides o The left hemisphere controls the right side of the body, and vice versa (lateralization) Hemispheric Lateralization  Left brain: language, speech, writing  Right brain: nonverbal, visualization, spatial skills     

Occipital lobe: vision Frontal lobe: sense of self, motor control Temporal lobe: Hearing, language Parietal lobe: sensation such as touch, temperature, and pressure Cerebellum: Posture, coordination

 Warnicke's aphasia: patient can produce speech effortlessly, but their comprehension is inhibited.

 Broca's aphasia: patients struggle to produce speech, but have comprehension of everything they are trying to say.  Neurological soft signs: behavioral signs that indicate a problem with brain functioning, such as clumsiness, slurred speech, poor hand-eye coordination, etc....