Textbook Notes (368,680)
Canada (162,066)
Psychology (9,696)
PSYC18H3 (275)
G Cupchik (49)
Chapter 6

Chapter 6.docx

7 Pages
Unlock Document

G Cupchik

Chapter 6Emotions and the Brain How Do Brain Mechanisms of Emotion WorkHuman brain has about 100 000 000 000 neurons and each has 10 000 synapses with some as many as 150 000Neuroimaging machine monitors biochemical events in series of conceptual slices through persons brain while computers take info and constructs visual images of brain to show regions have been most activemethos are noninvasive and include PET positron emission tomography and fMRINeurophysiologists stimulated parts of brain electrically and with pharmacologically active substances that affect chemical mechanisms of neurons applied generally as drugs or locallyHindbrain includes regions that control basic physiological processes o Medulla regulates cardiovascular activity o Pons controls human sleep o Cerebellum involved in controlling motor movementForebrain includes thalamus involved in integrating sensory info o Hippocampus critical for memory processes o Hypothalamus regulates important biological functions like eating sexual behaviour aggression and bodily temperature o Limbic systemstructures involved in emotions like amygdaleand cortex which most sets human brain apart from that of other speciesits growth of cortex in human species is closely associated with abilities to lead complex social livesfrontal lobes of cortex are involved in planning and intentional action as well as emotion regulationDescartes proposed that sensory stimuli pulled little strings that ran inside sensory nerves to open valves which would let fluids from central reservoir in brain run down tubes to inflate muscles o Thought was mechanism underlying human reflex o Now nerve that nerve messages are carried not by strings and hydraulics but by electric and chemical signals o Analysis of reflexas involving events that excite sensory receptors which send messages along sensory nerves to brain which send signals to motor nerves to work muscles Early Research on Brain Lesions and StimulationFirst substantaial theory of brain mechanisms of emotion was proposed by CannonWork in Cannons lab by Bard grad student of Cannon indicated that cats deprived of cortex were liable to make sudden inappropriate and illdirected attackssham rageo If fed artificially and tended cats could live for long time but whould show few spontaneous movements except angry sham rage o Observations prompted Cannon to propose that cortex usually inhibits expressionHess and Brugger complemented research on lesions with experiments using electrical stimulation that elecited angry behaviour not from thalamus but from hypothalamus which lies below it th Cannons and Bards formulation was continuation of 19 century hypothesis of nervous system proposed by HughlingsJackson o In view lower levels of brain hind brain are reflex pathways related to functions like posture and movement o Next levelevolved structures like emotion o Highest levelrecently evolved level cortex controls all levels below it o Children abound with uncontrolled emotion until cortex develops sufficiently to inhibit lower functions o Brain trauma leads to diminished activity of higher regions of brain releasing lower ones from inhibition Limbic SystemMacleantheory found inspiration in speculative paper of Papez who argued that sensory impulses from body and outside world reach thalamus and split into 3 main pathways o One goes in to striatal regionstream of movement o Neocortexstream of thought o Limbic systemstream of feelingInspired by Papez Maclean proposed human forebrain includes 3 distinct systems each developed in distinct phase of vertebrate evolution with each system fulfilling new functions related to its speciescharacteristic repertoireEarliest and most basic part of forebrain is striatal regions
More Less

Related notes for PSYC18H3

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.