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Phineas Gage was foreman of a dynamite crew working for the Rutland and Burlington Railroad in New England when a tapping iron, more than a meter in length and weighing 6 kg. shot through the left side of his head when a spark ignited the dynamite. Recovered in weeks but according to friends "Gage was no longer Gage." childlike, impulsive, given to profanity and drinking. He was fired, worked in a livery stable. then to South America to establish a coach line. Returned 8 years later, dying of epilepsy. He carried the tamping iron with him all those years. Phineas Gage
Orbitofrontal cortex • Orbitofrontal cortex inhibits hypothalamus, the area responsible for basic appetitive behaviors such as feeding, fighting, fleeing, and mating.
1890 - Friederich Golz calms dogs by cutting their brains. 1935 - Following demonstration by Jacobson and Fulton that frontal lobe mutilation produced a "calming effect" in monkeys, Antonio Egaz Moniz cut the frontal lobes of 20 of his psychiatric patients and reported a similar "calming" effect. 1936 - Walter Freeman and James Watts introduce a surgical technique for frontal lobe lobotomy into the U.S.A. Early 'technique' involved drilling burrholes, later Freeman developed his famous transorbital approach pushing literally an icepick into the brain via the eye sockets. 1942 - The icepick lobotomy has spread worldwide and by now approximately 5000 people are lobotomised each year during the 1940's! 1949 - Egaz Moniz wins nobel prize for his lobotomy techniques.
Neural Darwinism: growth & selection (or exuberance and elimination)
Gray matter maturation – myelination doesn’t finish in frontal lobe until 30 y or so • Adults use frontal lobe to recognize emotions; teens use amygdala
Environmental Control of Behavior Difficulties using cues from the environment to direct, control, or change personal behavior. Impaired ability to inhibit responses, leading to perseveration. Breaking rules and taking risks (e.g. gambling); not following task instructions Temporal Memory Impairment Short-term memory impairment Judgments about recency Impaired Interpersonal Behaviors: Social & Sexual Social & sexual behavior inappropriate or altered from previous forms Pseudodepression & Pseudopsychopathy Motor Function Disturbances Loss of fine movement Loss of speed and strength in hand & limb movement Poor programming of movements Poor voluntary eye gaze Broca's aphasia Loss of Divergent Thinking Frontal lobe damage shows a loss of divergent thinking in various forms (multiple correct answers). Loss of spontaneous behavior, e.g., speaking & verbal fluency, graphic designs & doodling, overall behavioral output (lethargy, initiation of daily routines Impaired strategy formation & planning, especially in response to novel situations Frontal Lobe Functions
Personality change • Environmental dependency • Mood disorders • OCD
Poor organizational strategies • Poor memory search strategies • Stimulus-bound behavior/environmental dependency • Impaired set shifting and maintenance
Wisconsin Card Sorting Task • Response inhibition - perseveration failures
GLP XTPD RSLGT ZMQ WXFG HLBG NAME INK COLORS
MAPLE BAR HORSE CHILD CLOUD FORK NAME INK COLORS
GLP XTPD RSLGT ZMQ SPR HLBG OSLGT ZQX RTRE YYP WXFG NAME INK COLORS ROSLG GWL SLPD RSLGT OMQ FGYT JBB RSLGT XLL LLFG TLG WXFG GLP RMS MQL XTPD RSLGT TTG HBG UJU LGT ZQP XLL ROLG GWL SLPD RGR ZMQ FGYT JUQ ELGT LLFG TLG
RED GREEN BLUE BLUE RED BROWN GREEN RED GREEN BLUE BROWN NAME INK COLORS RED GREEN BLUE GREEN BROWN RED BLUE GREEN RED GREEN BROWN BLUE RED RED BLUE BROWN GREEN RED BLUE GREEN RED BROWN RED BLUE GREEN BLUE BROWN RED GREEN BLUE RED GREEN BROWN
Stroop Task • Reading is overlearned, difficult to stop • Meaning of color word competes with ink name when incongruent ink-word correspondence • Ability to Inhibit Automatic Processes
Frontal Lobe Functions • Frontal areas modulate and control motor function, emotion, attention and other cognitive activity. • Impairments can be considered specific deficits of control. • Cognitive Impairment • IQ is unaffected, however subtle cognitive impairments remain.
Impaired Abstract Reasoning and Hypothesis testing • failure to maintain goal-directed behavior. • inability to perform abstract reasoning (requires complex associations between semantic elements, identifying super-ordinate categories • failure to generalize experiences into rules or general principles • Mental flexibility (set shifting problems) and distractibility • Disturbance of Behavior and Personality • lack of originality and creativity • inappropriate emotions and behavior, with little awareness of it • difficulty initiating behavior or stopping when started (perseveration). • Language Impairment • Low verbal production, little initiation of conversation, sometimes to mutism.
Impairment of Social Behavior • deficits in maintaining appropriate social responses. (even minor deviations in social behavior are noticeable). • generating appropriate behavioral options in social situations and choosing the best alternative. Often base behavior on concrete simple motivations and cannot comprehend more complex or abstract reasons for acting. • Confabulation and Reduplication Syndrome • tend to fabricate quick, impulsive answers to questions. • reduplication. Claims current environment (e.g., hospital) is actually another place. • Impairment of Motor Function • Problems with highly controlled, volitional components of motor control. • perseveration, incoordination, motor impersistence and hypokinesia as well as ideomotor apraxia. Worse for opposite extremities. • Impairment of Reflexes • inhibition of fundamental reflexes such as grasp and sucking. Patient will grasp when palm stroked. Patient cannot release object even when told to attend to the hand. Or patient compelled to suck on an object placed in his/her lips.
Understanding Language • Speech Origins: phylogeny, ontogeny (glottogenesis) • Language Acquisition Failures: autism, deaf of hearing parents, feral/neglected, phonological and syntactical problems • Language Loss: aphasias, hemispherectomy, split brain • Normal development – individual differences, bilingualism • Cultural differences • Its use and creation
What is Language? • Unique to humans or not • Continuity vs discontinuity theories • Nature of language • What constitutes language? Essential features
Hockett’s Design Features • Semanticity -- Specific signals can be matched with specific meanings.
Hockett’s Design Features • Arbitrariness -- No necessary connection between the form of the signal and the thing being referred to. No resemblance of elements. (Onomatopoeic words are not entirely arbitrary.)
Hockett’s Design Features • Discreteness -- Basic units of speech (such as sounds) belongs to distinct categories. No gradual, continuous shading from one to another in the linguistic system. Speakers perceive either a [p] or a [b], but not as blend, even if waveform falls somewhere between the two.
Hockett’s Design Features • Displacement -- Speaker can talk about things which are not present, spatially or temporally.
Hockett’s Design Features • Productivity -- Human languages allow speakers to create novel, never-before-heard utterances that others can understand.
Hockett’s Design Features • Traditional Transmission -- Individual is not born knowing their entire communication system (not entirely hard-wired) but must learn much about it to use it.
Hockett’s Design Features • Duality of patterning -- Discrete parts of a language can be recombined, reordered to create new forms.
Loss or impairment of language comprehension or production Aphasia
Spontaneous Speech • Fluent versus nonfluent • Paraphasias • Word finding difficulties • Articulation • Effort • Prosody
Auditory Comprehension • Single words • Phrases • Whole body commands • Syntax
Repetition • Single words • Phrases • Reading • Single words • Phrases Token test
Non-fluent Aphasias • Broca’s aphasia • Global aphasia • Transcortical motor aphasia • Mixed transcortical aphasia
Fluent Aphasias • Wernicke’s aphasia • Anomic Aphasia • Conduction aphasia • Transcortical sensory aphasia
Conduction Aphasia Fluent speech Good comprehension Poor repetition Poor naming Possibly lesion in arcuate fasciculus or its connections in inferior parietal lobule Wernicke’s Aphasia Fluent speech Poor comprehension Poor repetition Poor naming Posterior superior temporal lobe lesion (first temporal gyrus)
