Presentation on theme: "The Brain Divided into two hemispheres Mirror images in structure Connected mainly by corpus callosum Sensory and motor functions are contra-lateral."— Presentation transcript:
The Brain Divided into two hemispheres Mirror images in structure Connected mainly by corpus callosum Sensory and motor functions are contra-lateral
Major-Subdivisions Brainstem Cerebellum Thalamus Hypothalamus Limbic System Cerebrum
Medulla vital functions such as: cardiovascular system respiration muscle tone Pons regulates some stages of sleep alertness and arousal, attention Midbrain: visual and auditory processes reactions to moving stimuli movements in sex and aggression Cerebellum: Coordination of well-learned behaviors, feedback comparison of movements with intentions, balance Brain Stem
Thalamus: Simple analysis and relay of sensory information, like a telephone exchange. Hypothalamus: A waystation for pathways that regulate fighting, fleeing, feeding, sexual behavior. Damage affects-these behaviors. Limbic System. Amygdala rage, aggression, sex drive. (Psychosurgery for chronic sex offenders, violent criminals?) Hippocampus: Temporal organization of memories. Relation to Alzheimer's disease.
Cortex: The cerebrum's outer surface (means " bark or rind ") Surface is folded. A species complexity is related to amount of surface area. Folded to fit into smaller skull. A couple of deep folds: Lateral fissure, Central fissure. Divided into four "lobes" Frontal, Temporal, Parietal, Occipital.
Lobes have primary information areas and secondary association areas. Frontal Lobe: Primary motor cortex and association area. Produces planning, impulse control, judgment, motivation, perseveration, spontaneity. The Psychosurgery “frontal lobotomies”,were used to change behavior. Rarely used today. Effects of damage: Slowing of thoughts and spontaneity, perseveration, loss of self-awareness and emotional changes, lack of foresight and planning.
Temporal Lobe: Primary auditory area: auditory recognition, auditory localization. Leftside: language functions like naming, comprehension, etc. Rightside: rhythm, musical tones, spatial perception, spatial organization. Nearby Broca's area (frontal lobe) involved with language, too (speech production).
Occipital Lobe: Primary vision area. Damage to primary area will cause blindness, blow to back of head causes "seeing stars." Damage to association area causes inability to recognize objects or relate visual parts of object into whole. Parietal Lobe: Primary sensory area. Association areas coordinate senses into meaningful wholes. Rightside Parietal damage produces "sensory neglect" failure to notice stimuli on the left side of their body. Also arithmetic inabilities. Leftside Parietal - impaired reading, writing.
Lateralization generality: Left analysis, Right synthesis. Left hemisphere: analysis of serial events: language, naming, reading, mathematics, logic, hand movements during speech. Often accompanied by right eye glances while thinking about these things. Right hemisphere: synthesis of patterned events: Musical, artistic abilities; spatial perception, orientation; map reading; imagination, fantasy; body control, awareness; enumeration, touch location, nonspeech sounds. Often accompanied by left eye glances while thinking about these things
Lateralization generality: Right-handers: 95% are left hemisphere for language (writing hand below line). Left-handers: About 50 +% are left hemisphere for language (writing band above line) language is processed in both sides of brain.