Time perception

Question 1

Evidence for biological clocks being hardwired

Answer 1

Study by Aschoff: Ps maintain 25 hr clock when living in constant light environment

Question 2

How quickly do circadian rhythms adjust to different time zones?

Answer 2

1 day per .5 to 1 hr of time change

Question 3

How do day and night interact with the brain to produce the biological clock?
Evidence for neural basis of circadian rhythm

Answer 3

Day and night set the clock
Circadian rhythm established by suprachiasmatic nucleus in hypothalamus, receiving input from pineal gland and light (vision); pineal gland secretes melatonin
Ablating SCN and tumours cause random sleep cycles

Question 4

Perceptual moment

Answer 4

Minimum time needed between two events to determine if they occur simultaneously or successively

Question 5

Approximate times of perceptual moment found in research

Answer 5

30 ms and 125 ms

Question 6

Evidence for 30 ms perceptual moment

Answer 6

Experiment - Enns: 30 ms needed to detect which object appears first
Experiment - Sternberg: measured how much time needed for Ps to react based on short term memory; 25-30 ms needed to store stimuli in memory

Question 7

Micropatterns

Answer 7

Small variations in a pattern that occur so quickly you cannot see them

Question 8

Study using micropatterns

Answer 8

Efron: presented compound light stimulus consisting of 10 ms red followed by 10 ms green; percept was yellow; when duration increased to 15-20 ms, yellow appears slightly different

Question 9

Evidence for longer perceptual moment

Answer 9

Experiment - White: asked Ps to report how many clicks heard in an interval; accurate up to 5 clicks/sec; reponse plateaued at 6-7 clicks (150 ms), even when clicks at 25/sec ; argument: information “chunked” into 150 ms intervals
Efron: asked Ps to identify which pulse of light (of 2) was longer, with one locked at 1ms; reported same duration between pulses up to 50 or 60 ms; argument: perceptual moment = 60 to 70 ms

Question 10

Hoagland’s hypothesis

Answer 10

Internal biological clock that regulates metabolic rate and passage of time; physiological processes can impact clock speed

Question 11

Evidence for Hoagland’s hypothesis

Answer 11

Experiment on wife: percept of time slower when fevered; asked wife to count to 60 sec by 1 sec intervals; took 37.5 sec
Baddeley: asked scuba divers to do the same; took 70 sec

Question 12

Study on “time slowing down” phenomenon when in life threatening situation

Answer 12

Eaglemann: Ps wear perception chronometer on arm with LED numbers flickering in and out at rate too fast to be seen; dropped Ps 10 stories, asked them to read device; Ps could not

Question 13

Brain areas of biological clock

Answer 13

Basal ganglia: regulates clock via release of dopamine; more dopamine, faster clock
Cerebellum: timing of motor task
Prefrontal cortex: expected duration, anticipation

Question 14

Information storage size theory

Answer 14

Perceived time duration is based on amount of information committed to memory per unit time; depends on efficiency, complexity of encoding, number of events

Question 15

Evidence for information storage size theory

Answer 15

Study - Ornstein: Ps exposed to constant time interval (9 min); sounds occured at 40, 80, or 120 ms intervals; Ps asked to judge length of time; as sound frequency increased, time judgment increased; also found for visual and tactile stimuli

Question 16

What stimulus factors, other than number, influence time duration percept? Evidence

Answer 16

Complexity - Yeager: complex melodies judged longer than simple ones
Familiarity/predictability - Boltz: for familiar events, good judge of time; for novel events, judgment longer than actual
Organization (how information is presented and organized in a time inverval) - Mulligan & Schiffman: presented ambiguous drawing for fixed time interval; Ps asked to remember image; either given simplifying clue (label or caption) or not; cue aided storage and recall, reduced perceived duration of interval

Question 17

Recall effect

Answer 17

We estimate time duration of past event based on memory items stored

Question 18

Cognitive attention theory

Answer 18

Two processors: non-temporal information processor and cognitive timer; in standard perception task, attention divided between two; if attention more on cognitive timer, slower percept of time passing

Question 19

Why does time seem to speed up as we age?

Answer 19

We perceive passage of time between two events relative to our lifespan; we also get busier as we age

Question 20

Does the brain prioritize the short term or long term?

Evidence

Answer 20

Study - decision making: $200 now vs $210 in 7 days - Ps choose now; $200 in 6 weeks or $210 in 7 weeks - Ps choose 7 weeks
fMRI study: reveals two systems for short and long term decisions, always in conflict; short term more heavily weighed; only 1 output (behaviour): US housing crisis major example - people taking subprime mortgages for short term gain and long term cost